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Principia Mathematica 1713 - Up

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VIRI<br />

PR.&STANTISSIMl<br />

OPUS<br />

MOCCE


Quip totie animos veterum to&e Sophorum,<br />

plaque Scholas hodie rauco certamine vexanr,<br />

Obvia confpicimus ; nubem pellente Mathcfi :,<br />

QIX fi~peras penetrate donws, atque ardua Crrli,<br />

N E w T o N I au@ciis, jam dat contingere Templa#<br />

Surgite Mortales, terrenas mittite curas j<br />

A tcguc hint czligenz vires cognofcite Mentis,<br />

A pecudum vita Iongc longeque renlotz:.<br />

Qi Gpcis primus T,zbulis compeicere Czdes,<br />

Furra & Adulteria, & perjure crimina Fraudis ;<br />

Quive vagis populis circumdare rncenibus Urbes<br />

A&lxx ercl r ; Cererifve beavit munere genres ;<br />

Vel qui curarum lenimen prefit ab Uva;<br />

Vel qui Niliaca monfiravit arundine pi&OS<br />

Confociare L&05, oculiijue exponere Votes;<br />

Hupanam fbrtein minus extulit; utpote pauca<br />

In commune ferens m&x32 folatia vita2<br />

Jam vero Superis convivz admittimur, alti<br />

Jura poli tra&are licet, jamque abdita diaz<br />

Chuitra patent Nature, EZ rerum immobilis ordo;<br />

Et qua2 prateritis latuere incogniea ktxlis.<br />

Talia monfirantem juitis celebrate (hmaenis,<br />

Vos qui calefii gaudetis +&tare v&i,<br />

N 13 w T 0 N u M claufi reierantem erinia Veri,<br />

N E w T o N u hj ML& carum, cui peaore puro<br />

I%E~LIS adeft, totoque ince@t Numine mentem;<br />

NW fas eft propius Mortah attingere, Divas.


A<br />

D<br />

UN fiteres Mechanicam (uti AuEor .eJ Pappus) in rerun8<br />

Natwalium inzleJigatione maximi fecerint ; & Recentiores,<br />

mi&s formis Jubjavztialibus & qualitatibus o~c~lti~, Phlenomena<br />

Natzm ad leges Matbematicas<br />

in hoc Trd@& Mathefin excolere, quatenus ea ad Philofophiam<br />

Jv e at. Mechanicam were dupkm fiteres co%Jituertmt : Rationalem<br />

quce per Dernonjratiorres accurate procedit, &J .l?ra&i-<br />

Gllll. Ad PraEicam &e@ant Artes omnes hlantiales, a pjbtis<br />

utipe Mechanica nomen mutuatn ejf. Cisn azitem Art$ces parum<br />

accurute operart&leant, fit ut hlechanica omnis a Geonxtria<br />

ita diJt7ingtiutw, ut quicquid accuratum . fit ad Geometriam<br />

referatsn, quicpid mir~us dccuratum ad Mechanicam. ~ftamen<br />

errores non Junt Artis Jed Artz$cm. &i mintis accurate operatter,<br />

imperfelfior eJ Mecbanicus, f&F+! J @kf accrdratiJ%ne optrari<br />

pofet, hit f&et Mechanictis omnium perfe&@nus. Nam &<br />

Linearurn refhrum & Circulorum deJ&‘ptiones in quibus Geoe<br />

me tria fyhndattir, ad Mechanicam pertinent. Has leneas deJcribere<br />

Ceometria non docet led pa/Mat. Pojdat en&n ut Tyro<br />

ealdem accurate deJ&ibere prius didicerit quam liwen attingat<br />

Geometrix ;. de&, qtiomodo per has operationes Problematn fol-<br />

I<br />

‘r vafat~r~ docet. ReDas & ~irculoos deflcribere. Problemta$tint,;<br />

e, ::<br />

%P


nin ex viribus quibuJdam pendere pffe-, quibus corportim pa~t~c&?<br />

per GWJUS nondum cog&as vel in Je mutuo impelhtttr &Y fecundunz<br />

f&was regulares cohment, we1 ab invicem fugantur &<br />

recedunt : pibus qiribus ignotis, PkzloJophi baEenus Natwarn fru-<br />

.F ra tenifarunt. Spero auteln quad vel huic PhiloJophandi rtiodo,<br />

v’el veriori al&i, Yrincipia bit pojta km-em aliqtiam pmbebunt.,<br />

IB his edendis, Tip acut@nzur & i7.z ornni literarum gertere<br />

eruditi@zus Edt~~~mdus Hakius opwam nawavit , net Joluna<br />

?$pothktarum Spbahatu correxit & Schemta incidi curuv’it, fed<br />

etiam ~u@or fuit ut harm editionem aggrederer. $&ippe cum<br />

demon$‘ratanz a me Egwam Orbium ~-AeJlium impetraverat, rogare<br />

non dej%it tit eandem cum ~ocietxe Regali communicmem,<br />

&d deinde hovtatibus & benignis Juis au&i& efecit ut de eadem<br />

in hem emittendu cog&are incipercm. At poJl’quam NOtuum<br />

Lunarium haqualitates aggrefids e/yew, ,deinde etiam alia<br />

tentme c&piJTeem gud ad leges & menJuras Gravitatis & alidrum<br />

virhn, & Figwas a corporibus Jecundum datus quaJcunque leges<br />

attruE% deJ&ibendas, ad motus corporurn plurium inter se, ad<br />

motus corporum in Mediis rej!entibus, ad wires, denjtates &<br />

nzottis Mediorm, ad Orbes Cometarum & jmiliu Jpehnt, editionem<br />

in aliud tempus differendam ere putavi, ut cdtera rimam<br />

rer & una in publicuw darem. &jce ad motus Lunares @e@ant,<br />

(imperfe@a cum Jint,) in Corollariis Propojtionis LXVP. j&nul<br />

complexus Jum, ne &guh lnetbodo pro&ore quam pro rei dignitate<br />

propanew, 6 r J&l1 2 2 a t’ 2m d emon jf rare tenerer, & leriem reliquarum<br />

PropyBionum interrunzpere. Nonnuh Jero inroenta locir<br />

minus idoneis inJerere mahi, guam numer~m PropoJitionurvs<br />

(y citutiones mutare. Ut omniu candide leguntur, & defe&,<br />

in materia tarn dzj2li non tam reprehendantur, quanz norvis Le-<br />

@orurn conatibus inveJigentur, &<br />

benigne bkppleuntur, en&e rags.<br />

Dabam Cantabrigk e Collegio<br />

.S. Irinitatis, Maii 8. 1686.<br />

b


DI’I-3RIS<br />

fuarum fh&mentum defumunt ab Hypathefibus, etiamfi deinde<br />

&-undum leges Mechanicas accuratiffkne procedant j Fabdam qui-<br />

dem eleganrem forte & venufiam, Fabulam tamen concinllaro dicwdi<br />

funt.<br />

Melinquitur adeo tertium genus, qui Philofophiam-fiilicet Experimentalem<br />

profitentur. Hi quidem ex timplicifllmis quibus<br />

pofi’unr principiis rcrum omnium cauk~s derivandas effe volunt :<br />

nihil autem Principii loco aff%munt, quad nondum ex Phaznome..<br />

nis comprobatum fuerit. Hypothefes non comminifcuntur, neque<br />

in Phyficam recipiunt, nifi ut C&&ones de quarum veritare diTputetur.<br />

Duplici iraque Methodo incedunt, Analytica & Synthe<br />

tica. Naturaz vires legeCque virium fimpliciores ex iel&is<br />

quibufdam Phzenomenis per Analyfin deducunt, ex quibus deinde<br />

per Synthefin reliquorum confiitutionem tradunt. E-laze iila efi<br />

Phi]&ophandi ratio longe optima) quam prz ceceris merita ame<br />

p]eQendam cenfilit Celeberrimus Au&or notier. ]Manc folam utique<br />

dignam judicavit, in qua excolenda atque adornanda operam<br />

Euam collocaret. Hujus igitur illutkifimum dedit Exemplum,<br />

Mundani nempe Syfkmatis explicationem e Theoria Gravitatis<br />

felic&me dedu&am. Gravitatis virtutem univerfis corporibus inefl”e,<br />

fifpicati funt vel finxerunt ahi: primus Ilk & iblus ex Ap..<br />

parentiis demonitrare potuit, & fpeculationibws egrcgiis firmi&<br />

~LUTI ‘ponere fundamentum.<br />

Scio equidcm nonnullos magni etiam nominis Biros, przjudiciis<br />

quibufd;lm pIus 3equo occupatos, huic novo Principio agre aCTen*<br />

tiri potuiffe, & certis inccrta identidem ptztulifk Horum famam veJc<br />

licare non eit animus: Tibi potius, Benevole Le&or, illa paucis exponere<br />

Iuber, ex quibus Tute ipk judiciurn non intquum feras.<br />

lgittrr ut Argumenti fumatur exordium a hmplicrfimis & proximis;<br />

defpiciamus pauhfper qualis fit in Terrefiribus natura Gravita&,<br />

ut deinde cutius progrediamur ubi ad corpora ,Czlefiia, Iongi&ne<br />

a fkdibus no&is remota, perventum fuerit. Convenie jam<br />

inter amnes PhilofophoS , corpora univerfi CircUm terreikia gravitare<br />

in Terram. Nulla dari corpora vere levia> jamdt7dunl<br />

confirmavit Expcrientia multiplex. QUX dicitur Levitas relariva$<br />

non efi vera Levitas, fed apparens


and illrld concedi aquum ef?, quad Mathematicis .ratioljibus<br />

i coQitur & certiflitie demonfiratur; CCXpQGl nempe OlIlU&, quz<br />

moventur in linea aliqua curva in plano defcrigta, ~uazque radio<br />

duQo ad yun&um vel quickens vel utcunque lllOtU’I?1 dercribunt<br />

arCaS circa punRum illud temporibus proportionales, urgeri a<br />

‘$rir&Us quz ad idem pun&urn tendunt. Cum igitur in confer0<br />

fit spud Afironomos, Phecas primarios Circulli S0krn, [ecundarios<br />

vero circum fuos primarios, areas defcribere temporibus proportionales<br />

j confequens efi ut Vis illa, qua perpetup detorquentur<br />

a Tangentibus re&ilineis, & in Orbitis curvjlinels revolvi coguntur,<br />

verfils corpora dirigacur quar: fita fht In Orbitarum tentris.<br />

H3ec itaque Vis non mepte vocari poceb reQxx%u qui&m<br />

corporis revolventis~ Centripeta 3 .rei‘pe&u autem Corporis tentralfs,<br />

Attraniva j a puacunque demum cauia oriri fingatur.<br />

Qin & lmc quoque concedenda fun& ik Matkematice demonftrantur:<br />

Si corpora plura MOW aquabili revolvantur in Circulis<br />

coacentricis, & quadrata temporum periodicorum fint ut cubi difialitiarurn<br />

a centro ,communi; Vires centripetas revolventium<br />

fore reciproce ut quadrata difiantiarum. V& fi corpora revelvantus<br />

in Orbitis quaz hunt Circulis firkim% & quiefcant Orbitarum<br />

Apfides; Vires ceiltripetas revolventium fore reciproCe ut<br />

quadrata diihntiarum. Obtinere cafhm alterutrum in Plan&<br />

univerfis conkntiunt Afironomi. hque Vires centripeta Planetarum<br />

omnium funt reciproce ut quadrata dihntiarum ab Orhum<br />

centris, Si quis objiciat Planetarum, & Luna: przfertim,<br />

Apfides non penicus qukfcerej fid motu quodam lento ferri in<br />

conleyuentia : relponderi porea, etiamfi concedamus hunt maturn<br />

tard~fhum exindh profe&um effe quod Vis centripetaz proportio<br />

aberret aliquantum a duplicata, aberrationem illam per<br />

computzum Mathematicum inveniri poffe & plane infenfibilem<br />

effe. Xpfa enim ratio Vis centripctae Lunaris, quz omnium maxime<br />

turbari debet, pauIulum quidem duplicatam fiperabit; ad.<br />

lianc.vero kxaginta fere vicibus propius accedet q,uam ad triplicaram.<br />

Sed verior erit refponfio!, fi dicamus hanc Apfidum :p,rogreffionem,<br />

non ex aberratione a duplicata proportione, fed ex -a’lda<br />

prorfus diver& caufa oriri, quemadmodum egregie commonfiratar<br />

; in hat Phllofophia. Retiat ergo ut ‘57ires cencripetx, quibus Pla-<br />

1<br />

neta: primarii tendu~nt verfus Solem & Gcundarii verbs primaries<br />

I<br />

&OS, ihat accurate mt qwdrata difiantiarum reciproce, ..<br />

I<br />

h<br />

Ex<br />

e


PR&FA<br />

ax iis quz ha&enus di&a font, conitat Planetas in Orbitis fuis.<br />

retineri per Vim aliquam in iprOs perpetuo agentem: confiat<br />

Vim illam dirigi kmper verfus Orbitarum centra: confiat hujus<br />

egcaciam augeri in acceffu ad centrum, diminui in recefTil ab eodem<br />

: & augeri quidem in eadem proportione qua diminuitur quadratum<br />

difiantia 9 diminui in eadem proportione qua diftantis<br />

quadratum augetur. Videamus jam, comparatione initituta inter<br />

Planetarum Vires centripetas & Vim Gravitatis, amon ejufdcm<br />

forte fint generis. Ejufdem vero generis erunt, fi deprehendantur<br />

hint & inde leges eEdem eademque af&L”ciones. Prim0 itaque<br />

Lunge, qura: nobis proxima efi, Vim centripetam expcladamus,,<br />

Spatia refiilinea, quaz a corporlbus e quiete demifis dato tempore<br />

fub ipib motus initio defkribuntur, ubi, a viribus quibufiunque<br />

urgenrur, proportionalia Cunt ipfis viribris: Hoc ucique confequitur<br />

ex rariociniis Mathematicis. Erit igitur Vis centripeta<br />

Lun;e in Orbita fi~a revolvenris, ad Vim Gravitaris in fuuperficic<br />

Terra?, ut fpatium quod tempore quam minima defiriberet Lulla<br />

defccndendo per Vim centripetam verfus Terram, G circulari omni<br />

motu privari fingeretur, ad fpatium quad eodem tempore quam<br />

minima defcribit grave corpus in vicinia Terra, per Vim gravitatis<br />

fux cadendo. Horum fpatiorum prius azquale ef% arcus a Luna<br />

.per i&m tempus dekripti finui verlb, quippe qui Lun3e tranflatioqem<br />

de Tangente, h&am a Vi centripeta, metitur; atque a&o<br />

eomputari potelt ex datis turn Luna: tempore ,periodico tup diitantia<br />

ejus a centro Terrz:. Sparium pofierius invenicur per Experimenta<br />

Pendulorum, qtiemadmodum docuit Htigenius. Inito<br />

itaque calculo9 f~>atium prius ad fpatium pofterius, fey vis tentripeta<br />

Lunar in Orbita fia revolverltis ad vim Gravitatis in fup&&e<br />

‘Terra, eric ut quadratutn femidiametri Terry ad Or-&-e<br />

f’midiarnetri quadrarum. E,indem habet rationem, per ea qux<br />

fuperiu,s oitenduntur, vis centripeta Lunar: in Orbita fua ~cvolventis<br />

ad vim Lung centripecam prope Terrx fiiperficiem. Vis<br />

iracluc c&ntrjpera prope Terra fiiperficiem z~q~,alis efi vi Gravita-<br />

,&SC,. :,Non’ergo diverGz funt vires,. fed una atquc cadSem :’ fi enin;l<br />

diver& effent, corpora viribus conjunBis duplo celerius in Terram<br />

caderent quam ex vi fola Gravitatis. ConfIat igitur Vim<br />

illam centripetam, qua Luna perpetuo de Tangente vel trahirllr<br />

vel i,mppellhw 232 in Orbita retinetur, ipkm effe vim Gravjtatis<br />

$ert&ris ad Lunam ufque pertingcntem. E,t rationi quidem ~011~<br />

$&taneum elR ut ad ingenrcs difiantias illa fefe Virtus extendat,<br />

cQm


EDVlX3RI.S<br />


P AZ F A I 0.<br />

Jgitur Comctas in SeBionibus Conicis umbillcos iii centid Sbjis<br />

habentibus moveri, & radiis ad Solem dutiis areas temporibus<br />

proportionales dekribere. EX hike vero Phznomenis manifefium<br />

efi & P&thematice cornprobacur, vires illas, quibus Cometa$<br />

retineneur in orbitis fiiis, refpicere Solem & effe reciproce UC quladrara<br />

difiantiarum ab ipfius centro. Gravitant itaque Comeraz<br />

in Solenl,: atque adeo Solis vis atcraf%va non tanium ad’ corpora<br />

Planetarum iii datis diftantiis. & in.eodem fere plano collocata,,<br />

fid ctiam ad Cometas ii1 diverfifimis Czlorum regionibus & in<br />

diverfifimis difiantiis pofitos pertingit. Hlnc igitur efi natura<br />

corporum gravitantium, ut vires fuss edant ad omnes difiantias in<br />

om’nia corpora gravitantia. Inde vet-o kquitur, Planetas SC Cometas<br />

univerfos k mutuo crahere, Sr in fe mutw graves effe’:<br />

quod etiam co’nfirmatur ex perturbationc Jovis & Saturni, Afironomis<br />

non incognita,& ab a&ionibus horum Planetarum in k invicem<br />

oriunda ; quin & ex mote illo‘ lentiflimo Apfidum, qui fupra<br />

memoratus eit, quique a cauij. confimili proficifcitur.<br />

Eo demum’ pervenimils ut dicendum fit, & Terram, 8~ Solem &<br />

corpora omnia cazlefiia, qua2 Solem comitantur, fi mutuo attrahere,<br />

Singulorum ergo particula: quaque minim= vires Cuss attraaivas<br />

habebunc, pro quanticate mater& pollentes; quemadmodum fupra<br />

de Terrefiribus, oflenrum efi. In dive& autem difkantiis,<br />

erunt & harurn vires in duplicata racione difiantiarum reciproce:<br />

nam ex particulis hat lege trahentibus componi debe‘re Globos<br />

eadem lege trahentes, Mathemarice demonltratur.<br />

Conclufiones pracedehtes huic innituntur Akiomati, quod a<br />

nullis non recipicur, Fhilofophis j IEffeEtuum fcilicet ejuCdem generis,<br />

quorum nempe quaz cog.nofcuntur proprietates easdem fiunt,<br />

eafdem effe caufas & eafdem efie proprietates qua: nondum cognofcuntur.<br />

Quis enim dubitat, fi &avitas fie caufa defcenrus<br />

Lapidis in Ewo~a, quin eadem fit caufa defcenfus in America?<br />

Si Gravitas mutua fuerit inter Lapidem & Terram in Ewopa;<br />

quis negabit mutuam effe in America? Si vis actraRiva Lapidis<br />

& Terrae componatur, inzEzlropn, ex viribus attra&ivis partium 5<br />

quis negabit fimileni efi% compofXonem’in America? Si attra&io<br />

Terra: ad omnia corporum genera & ad omnes difiantias propa?<br />

getur in Ez,~upa; quidni pariter propagari dicamus in America?<br />

In hat Regula fundatur omnis Phrlofophia : quippe qua’ iirblata<br />

nihil :a@rmare pofimus de Univerfk Con~ftit~tio’ rerum’ fingula-<br />

rum innotefcit-per Qbfirqationes & Ex@rimenta: inde vero non<br />

c<br />

-nifi


nifi per hanc Replam de rerum univerfarum natura judica-.<br />

mus.<br />

Jam cum Gravia fint omnia corpora, qua2 apnd Terram vel i.n<br />

CaAis reperiuntur, de quibus Experimenta vel Obkrvationes infiitucre<br />

licet 5 omnino dicendum erit, Gravitatem corporibus univerfis<br />

compctere. Et quemadmodum nulla concipi debent COTpora,<br />

quz non lint: Excenla, Mobilia, Sr Impenetrabilia; ita nulla<br />

cotlcipi $&se, qu.a noI1 lint Gravia. Corporum Extenfio, Mobi-<br />

Bitas & Impcnetrabilitas non nifi per Ex.perimenta in.norefcunt:<br />

eodem plane mod0 Gravitas innotefck Corpora ornnia de quibus<br />

Obkrv;:tiones habemus, Extenfa funt SE Mobilia & Impene--<br />

:r;libilia,: & inde concludimus corpora univerk ct,iam iIla de qui-.<br />

bus OhTervationes non habemus, Exten& effe & Mobilia & lm,-<br />

genetrabilia. IIta corpora omnia lunt Gravia, de quibus Obkrvationes<br />

habemus : & .&de concludimus corpora univerti, etiam.<br />

illa de quibus Oblervationes non habemus, G-rauia eR’e. Si q,uis.<br />

dicht corpora Srellarum inerrantium non effe Gravia, qukdoqui-<br />

dcm. eorum Cavitas nondum eit obkrvata; eodem- argumento<br />

dicere Iicebit neque JXxtenG eiTe, net MobSa, net Impenetrabilia,.<br />

cum haz Fixaru.m affetiiones nondum fin.t obkrvatz:. Quid opus,<br />

65-e verbis I Inter primarias qualitates corpor\LF univerfk-urn ve8<br />

Gravitas habebit Iocum~ vel Extenfio, Mabrhtas, 62 Xmpenetra-.<br />

bilitas non habebunt. Et natura rerum vel. re&e explicabirur<br />

per corporum Gravitatem, vel non re&e explicabitur per corparum<br />

Extenfionem, Mobilitatem, & Impenetrabilitatent.<br />

Audio nonnullos hanc improbare conclufionem, & de occult&<br />

quslitatibus nefcio quid mu&are, Gravitatem kilicet (hxxdtu~..<br />

efi quid, perpetuo. argutari Lolent; occultas vero cau&s prosul<br />

efi ablegandas a PhifoCophia.. His autem facile refponP<br />

detu.r; occultas eZfe caufZzs!, non ilIas quidem quarum exiflentia.;<br />

per Qb&rvationes clarifirme demonfiratw9 Ted has folum,quarum I<br />

&uIta efi. Sr fXtta exifientia nondum vet’0 comprobaca, Gravitas..<br />

ergo non erit occulta caufa motuum caiefiium ; fiquidem ex Pkaomenis<br />

oficnfum eft, hanc virtutem revera exifiere., Hi p&us,,,<br />

ad occultas~ co~nfugiunc caufas ; qui nei‘cio quos Vortices, mater&.<br />

clljufdam prorfus fiQkia 8i: d’enfibus omnina ignotz, molibyk<br />

Sdem. r.egendis pr&iciuntz<br />

Ideone autem Gravitas occulta: caufi dicetur, eoque no&e.<br />

rejicietur e Philo@phia, quad cauij ipfius Gravitatis occulta e&<br />

C&Z’, aondum. itwenta.~. C&i. fi.c ..fiat,~n.t $,. videant ta,equid flatuam.


)l T 0 R I s<br />

ridebitur qui finget Elaterem, & ~8 .Hyp@hefi fit ,pC~qr~~~Cr~?,+z~+<br />

$&a moruln lndicis explicarc fiifcipiet : oporturt elmn InternTG?<br />

~Jachin~ fabricam penitius perf‘crurari~ Ut ita mOtUS propo&iti prr.ecipiutn<br />

verum exploratum habere poffct. ltdem vel non abfimile<br />

ferecur judiciurn de Philofophi? illis, qlli maria quadarn fubcilifima<br />

Cd3s effe repletos, ham aucem in ‘Vortices rndefinen,ter<br />

agi voluerunt4 Nam fi f3hl-enomenis yeI accuraeif7lme Catisfac$&<br />

fiof&nt ex HypOtildibUS fUuiS j verasn tamen Philofaphiam tradidi@,<br />

& VeraS CaUfiS motuum cslefiium inveni& nondum &-<br />

cendi runt; rlifi vel has revera exikre, vei iaitem alias non exj&e<br />

demonfiraverint. lgitur fi ofi~nfi~ffl fuerlt 3 univer{o&nl<br />

~orporum At&Qionem habere verum locwn in rerum -natura 3<br />

quinetiam 0ltenGim FuFrit, qua ratione lotus OnWes c?Ules ah<br />

inde [olutionem recipiant; vana fkerit St merit0 derjdenda obje&$,<br />

fi quis dixerlt eoiaem mom per Vortices explicarl debere, $ar.nfi<br />

id fieri pop vel maximr: cqnceirerimus. Non autef? concedimus ;<br />

Nequeunt enim ullo pa&o Phxwmena p$r VqrEys expIic&;<br />

quad ab Au&tore nofiro abunde quidem & cIarlfirWs ratior+&kls<br />

evincitur; vt f$nn’iis plus aequo induIgeant oporteac, qui inep-<br />

#@ik figment0 refarciendo, noyifque porro commentis ornando<br />

infekcem operam qddicunt.<br />

Si corpqra, Planetarum & Cogetarw circ! Solem defeg-ar3,tqg<br />

a V’orti&bus; oportet corpora deIata Sr Vortwm partes* ppoximq<br />

+nbienee,s. eadem velqcitatb eademqu!: curfus detcrminatidqe. ~19~<br />

veti, & eandem Aabere denficatem yeI qandem Pim ine& pro<br />

mole. materiz. Coy It at: verq Planetas F Cometas, dum verfan..<br />

zur m iifdem rqgionibus ~;pl~ru~~ velocitatibus variis variague.<br />

eurfu,s. determinatione, m,overi. Necefirio itaqw Eequitur, ut<br />

]%luidi calefiis partes ilIz, qux iil,nt: ad ealrdem difiantias a Sole,<br />

revolvantur eodem txnl.pore in plagas dive&s cum diverfisL velocitatibus:<br />

etenim alia opus erit diretiione & velocitare, ut tran-<br />

Gre pofht l?lan~tx J alia, UT t,ranfire pofint Caper&, Qod cam<br />

%xpIicari nequ.eat ; vel fatendtxm erit, univer& corpora calcaia<br />

aon deferri a materia, Vorticis 3 vel dicel>dum .erit, eorulldem 1110..<br />

;us. repetenclos eOk non a,b WI?, eo$emque Vortice, fed a plur&us<br />

qui ah invicem diverfi fint, ,I&nq,ue Tpatium, Soli, circumje&um<br />

gervadant.<br />

Si plures Vortices in code&n. fpati9 contineri, & fefe. m”tuo pen,etrarc3<br />

motibtirque diverha revolvi, ppllanturj quoniam bi mow<br />

tus debcnt effe conformes: delat,orum corporun2 mot&us, qui<br />

.L filn~.


PRAFA.<br />

funt fumme regulares, c% peraguntur in fk&ionibus Conicis, nunc<br />

valde eccentric& nunc ad Circulorum proxime formam accedentibus;<br />

jure qwrendmm wit, qui ficri pofCt, ut iidem integri conferventur,<br />

net ab a&ionibus marerk occurfantis per tot &uIa<br />

quicquam perturbentwr. Sane fi LllOtUS hi f%%tii i?lnt magis cornpofiti<br />

8~ difficiIius cxplicantur 9 cluam veri illi motus Planetarum<br />

& come tarum j frufira mihi videnrur in Philofophiam recipi :<br />

omnis enim Caufa deber effk EffeC’ru Cuuo fimplicior. ConceKa<br />

TFabuIarum licentia, affirmaverit aliquis Planetas omnes 8-z Cometas<br />

circumcingi Atmo$kw+is 9 adinfiar Telluris nofkrz; qua quidena<br />

Wypothefis rationi magis confencanea l,idcbitur quam Hypothefis<br />

Vorticum. Affirmaverit deinde has A rmofphazras, ex natura<br />

fua, circa Solem moveri & Se&ones Conicas dcfcribere; qui<br />

fane motus multo facilius concipi pot&, qyam confimilis motes<br />

Vorticum fe invicem permeantiiam. Deniquc Planctas ipfos &<br />

Cometas circa Solem dcferri ab Atmofph:xris i‘uis credcndum eEc<br />

fiatuat, & ob repertas motuum czlefiium caufas criumphum a&at.<br />

QXquis autem hanc Fabulam rejiciendam effe puret, idcm & alter<br />

rom Fabulam rejiciet : nam ovum non elt ovo fimilius, quam Hypothefis<br />

Atmofphzrarum Hypothefi Vorticum.<br />

Docuit Gali,kw, lapidis projeQi & in Parabola moti deflexionem<br />

a curfu retiilineo oriri a Gravitate lapidis in Terram, ab ocwIta<br />

kilicet qualitate. Fieri. tamen pot& ut alius aliquis, nail<br />

ac,ycioris, Philofophu~s caufaxn aliam comminifcatur. Finger igitq,r<br />

ille materiam quandam fibtilem, qu3: net vifu, net ta&u,<br />

nec;lue u,llo fenCu percipitur, verfari in regionibus qua proxime.<br />

cogtingunt Telluris Cuperficiem. Hanc autem materiam, in diverfas<br />

plagas, variis & plerumque contrariis motibus ferris & lineas<br />

Parabolicas defcribere contender, Deinde vero lapidis deeexionem<br />

pulchre fit expediet, & vulgi plaufum merebirur. Lapis,<br />

inquiet, in Fluid0 illo iubtili narat; & curfili ejus obfequend9,<br />

non. poeefi non eandem una femitam dekribere. Fluidum<br />

v,ero movetur in lineis Parabolicisj. ergo lapidem in Parabola<br />

mpveri. necefli efi. Qis. nunc non mirabitur acutifiimum hujufce<br />

Qhilofophi ingenium ,’ ex caufis Mechanicls, materia fcilicer &,<br />

mqtu, phznomena Nature ad VuIgi etia,m captum praclare deducentis.?<br />

Qis vero non fiibfannabit bonum illum GLzZ~~~WB, qui,,<br />

magna:, molimine Mathematico qualitates occultas, e Phllofophia<br />

fqliciter exclufas9 denuo revocare fuuitinwerit ? Sed puder nugis j<br />

c&us immorari.<br />

Sum-


EDITORIS<br />

Summa rei hut tandem redit: Cometarum ingens efi numerug;<br />

motus eorum fimt filmme regulares, & eafdem leges cum Planetarum<br />

motibus obfervant. Moventur in Orbibus Coni& hi orbes<br />

funt valdc admodum eccentrici, Feruntur undique in o_mnes<br />

Cdorum partes, & Planetarum rcgiones liberrime pertranieunt,<br />

& fk.pe contra Signorurn ordinem incedunt. Hzc Phenomena<br />

certiflime confirmarltur ex Obfervationibus Aitronomicis: Sr per<br />

Vortices nequeun t explicari : 11x0, IX quidem cum Vorticibus<br />

Planetarum confifierc pofl‘unt. Cofiletarum motibus omnino locus<br />

non erit; nifi materia illa fiQitia penitus e Calis amoveatur.<br />

Si enim Planetaz circum Solem a Vorticibus devehuntur 5 Vorticum<br />

partes, quz proxime am biunt unumquemque Planetam, ejufdem<br />

denfitatis erunt ac Planeta j uti gupra ditium efi. Itaque<br />

mnteria ilIa omnis quz contigua efi Orbis rnagni perimetro, parem<br />

habebit ac Tellus denfitatem: qua: vero jacet intra Orbem<br />

magnum atque Orbem Saturni ‘, vel parem vel majorem habebit.<br />

Nam ut conRitutio Vorticis permancre pofit, debent partes minus<br />

den& centrum occupare , magis denk longius a centro abire.<br />

Cum enim Planetarum tempera periodica fine in ratione fefquiplicata<br />

difiantiarum a Sole, oportet partium Vorticis periodos<br />

eandem rationem krvare, Inde vero iequitur, vires centrifirgas<br />

barum partium” fore reciproce ut quadrata difiantiarum. Qua:<br />

jgitur majore intervallo diitant a centro, nituntur ab eodem recedere<br />

minore vi: unde ii minus den& fuerint, necefi e& UC cedant<br />

vi majori, qua partes centro propiores afkendere conantur.<br />

Afcendent ergo denfiores, dekendent minus denfz, & lacorum<br />

fit3 invicem perrnutatio ; donec ita fuerit difpofita atque ordinata<br />

materia fluida cotius Vorticis, ut conquiefcere jam poirrt in zquilibrio<br />

confiituta. Si bina Fluida, quorum diverfa efi denfitas,<br />

in. codem vak continentur ; utique futurum eit ut Fluidum, CUjus<br />

major efi denfitas, majore vi Gravitatis i&mum petat locum :<br />

Qk ratione 11on abfimili omnino dicendum efi, denfiores Vorticis<br />

partes major, .vi centrifuga petere fupremum locum. Tota igitur<br />

illa & multo maxima pars Vqrtick, qw jacet extra Telluris<br />

orbelw, denfitatem habebit atque adeo vim inertia: pro mole -ma-<br />

‘teriz, quz non minor erit quam denhtas & vis inertix: Telluris:<br />

in,de vero Cometis traje&is orictur ingens refifientia, & valde adarrodum<br />

fenfibilis; ne dicam, qua: motum eorundem penitus fifiere<br />

z atgue abl‘orbere poffe merit0 videatur. Confiat autem ex motu Cometarum


EDITORIS<br />

fhs indignatn.’ Q& Cazlos materia 19 uida repletos effe vaIunt,<br />

ilarlc vero 110~~ inertem effe fiatuunt; Hi verbis tollunt Vacuum,<br />

re ponunt, Nam cum hujufmodi materia fluida ratione nwlla<br />

fecerni pofiir ab inani Spat-m difputatio tota fit de rcrum nominibus,<br />

non de naturis. C&od ii aliqui fint adeo wf$ue dediti<br />

MateriE, ue Spatium a corporibus VXUU~I nullo pa,@o, admittendunl<br />

credere velint 5 videamus quo tandem oportcat illos<br />

pervenire.<br />

Vel enim &cent hanc, quam confingwnt, Mundi per omnia.<br />

pleni confiitutionem ex voluncate Dei profe&am effe, propter’<br />

cum finem 3 UC operationibus Naturze Cubiidium pr&ns haberi<br />

pofl’et ab -&there fubtilifflmo CUII&I permeante & inlpIen,tej<br />

quad tamen dici non pocefi, fiquidem jam ofienfum elt ex Co&*<br />

nietarum plwznomenis J nullam efJ’e hujus AZtheris: efficaciam: veli<br />

&cent ex voluncate Dei profeaam efi, propter finem aliquern<br />

Jgnocum ; quod neque dici debet, fiquidem dive&a Mundi con-”<br />

ilitutio eodem argument0 parker fiabiliri poffet: vsl denique<br />

non dicenr ex voluntace Dei profeaam, efk, fed ex necefitate*<br />

uadam Nacura. Tandem igitur dclabi. oporcet in fzces fordi-<br />

1 as Gregis impurifflmi. Hi funt qui fornniant- Face univerfa,.<br />

regi, non Providen tia j Materiam ex necefiitate CuaGmper & ubique<br />

extitifi , infinitam efXe 2% zternam. @ibus pofitis-, erit,<br />

etiam undiquaque uniformis : nam varietas formarum cum necef-,<br />

fitate omnino pugnat. Erit eciam immota: nam fi necefiria:<br />

msveatur in pIag:lm afiquam determinatam, cum determinata aliqua<br />

veloci ta te j pari neceilltate movebitur in plagaw divercam,;<br />

cum dkerfa velocitate ; in plagas autem divertis, cum’ cl&&@<br />

velocicatibus, moveri non pore@; oportet igicur immo,tam effe:<br />

Neutiquam profeCto potuit oriri Mundus a pulcherrimti fdrmaL<br />

rum &. motuum varietate difiinQus, nifi ex Ii berrima-. volunsate)t<br />

cup&a providentis & gubernantis Dei.<br />

Ex hoc igitur fonte prornanarunt ilk ornnes quz dicun,la.f,;<br />

Natura leges : in .quibus multa fane fapientiflimi confilii, nuljdi<br />

n.eceGtatis apparent vefiigia. Has :proinde non ab inuertisf can-;:<br />

jeEturis t petere, I”ed Obfervando ,atque Experiendo. addi&erc d&<br />

bernus. Q$ verz. PliyGc8 principia Legefque rerum, fola mQn&<br />

$is.: vi & intern0 rationis lumine fretum, invenire fe poffe co&<br />

dit; hunt .oportet vcl fi’atuere Mundnm ex necefitate fuiflcl! Legefque.<br />

propofitas eex.. eadem necefirate. fequi; vel fi. per v&nr<br />

-ta&cm Q.ei .,cQ,flfikU&W fit ardLk khW& & tame@ ,hbmunoionem<br />

mifelhm,


HXfXXIIS<br />

J?R&FATIo.<br />

debeo: Huic &Tuas quz debentur gratias, LeBor b~~~~~olQ tibh<br />

denegabis. Is enim, cum a longo tempore Celebeirlllll AuEttori~<br />

amicitia intima frueretur, (qua etiam spud Poiteros cen%ri tion<br />

minoris xftimat, quam prnpriis Scriptis (1I.W literat orbI iti deliciis<br />

fiint inclarefcere) Amici iimul faIna: 8;r fcie:nt$Sum inwe+<br />

mento confuluit, Itaque hum Exemplaria prioris Edlt’lafils rariG<br />

&a admodum & immani pretio coemcnda fuperefknG fu?fit IW<br />

crebris eflagitationibus & tantum non ,objurgando perPllt &hique<br />

Vjrum PfzfiantiiTmum, net modiitia minus qtianl eruditi;<br />

one fiiunma Tnfignem, ut .novam hanc Operis Editioned, per omnia<br />

&matam denuo 8~ egregiis infiuper acckUion$bus ditatam, Gs<br />

fimptibus & aufpiciis prodire pateretur: Mihi ~3% pro jure<br />

fi~o, penhm “non ingratum demandrivit, ut quati poar eme%date<br />

id fieri curarem.


DE@rlfi~I?IDMES.<br />

1’ A G.<br />

ASx~oMAAAA, SIVE LEGES MOTUS. I.2<br />

‘1>E ‘hkr>‘TU CQRPORUM LIBER DRIhlUS.<br />

's E CT. I. E &f e&do ralrionzlm primarum & ultimalVW@.<br />

24<br />

SENT. :][I. D e inzrentione V%ium centripetarum. 34<br />

$ E c T. 111. De motzi I orporum in C’onicis jk%onibus eccentri-<br />

CiS. 4’8<br />

s Et T. IV. De inwntione Qrbium Elbpicorum, ~drd$o/icorum~<br />

@FJ YIypeddicorum ex t.~mbilico dato. J9<br />

5 B *c T. V. De kwentione &b.krn uhi Umbilicus neuter datum. G G ’<br />

5 E % T. ‘$% !De inwetitione Motuum


DE h4OTU CORPORUM LZBER SECUNDUs,<br />

s E CT. 1. E Motu corporurn quihs re/i/titw in ratione<br />

Felocitatis. 211<br />

S E c T. 11. De Motor corporm~ qtdhs re/$%ur in duplhata ra.<br />

tione YeIo&atZs. 2.20<br />

S E c T. III. De MO& carporum q&s reJij?izW partim in ratione<br />

;trelocitatis, partim in +[dem r&one duplicata. 245<br />

S E c T. IV. lie corporum Circduri motto ilz Mediis rejJentibw.<br />

“53<br />

S E c T. V. De de$tate ~6% compreflone Fltiidorum, deqtie fly-.<br />

drojhticu.<br />

2Go<br />

S E c T, VI. De Motto & Rejflentia corporum Fwaependulorum<br />

27%<br />

S B c T. VII. De motu Fhdornm & rejientiu Pry*efi%mv, 29 J.<br />

‘S E c T. VIII. De motu per F&da propagate. 3 29<br />

s E c T. Ix. De mote Circzduri Fltiidortlm. 345<br />

. DE MUNDI SYSTEMATE LIBER TERTIUS.<br />

EG~LAE PHILOSOPHANDI<br />

PHANOMENA<br />

PROPOSITIONIS<br />

SCHOLIUM GENERALE.<br />

317<br />

359<br />

362<br />

4.81<br />

PHILO-


2 ~HI~cJsO:PHIX NA,TURAEK<br />

DEFINITIO<br />

III.<br />

lEfzc fernper proportionalis efi Cl0 colpori,, Ileque diEer-t quitquam<br />

ab hertia rnafh nib in modo conciplendr. Per inertiam<br />

materiq fit Llc corpu$ 0mne de fiats fU0 Vd quiefcendli vel maven-<br />

di difficuker deturbetur. Wnde etiam vis infki nomine fignificau..,<br />

riflimo Vis Inert& dici p&.3. Exercet vero corpus ~NIC vim iblumnlodo<br />

in mutatione @atus fui .per vim aliam in k $pre@rn fit$a j :<br />

&fiq; exe &itiu.ai’cjuS rub. diverio refpe&u Sz: Refi’fientla 8~ Impetus :<br />

recaencia, quaGenUS ,corptis Ed c,on@rvamdyn Raturn f~um reIu&a-<br />

Fur vi impreffae j impetus, quatenus corpus Idem, VI refifientis ob->.<br />

Ihx~li difficulter cedendo, conatur fiaturn ejus mutare. Vulgus.<br />

refifientiam quiekentibus &. ir@petml: ilioventihs tribwit : fed mo.-.<br />

tuS & quits, uti vulgo concipiuntur, refpeh Co10 difiinguuntur<br />

$3 invice,g !, neq;, Cernpc;r, Vgfe’~quie-Gxnt qu;1: VU@2 tanquant.q@s<br />

kentia ipeEtantur. ,, c ,<br />

D-3ZFINl-TIO<br />

FT.. Iwprefa Ed atGo in corpus exercita,<br />

IV<br />

a,d mutandum ejus~$izt~~<br />

cud quie[cendj ~sl moczlendz’‘uniforwa’ter in dire&m. ,_ .,<br />

ConfiSt h~c vis in a&ione fola, neque pOtI a&ionem permali&<br />

in corpore. Perfeverat enim corpus in ilatu,~otnni novo per f&m,<br />

vim inertia; Bit autem vis impreffa diverkrum originurn,. .ut ,e,k<br />

I&n, ex Pfefinione, ex vi Centripeta.<br />

DEFIN~ITIO.<br />

V..<br />

~5% Centpijeta f/t, qua cov+pora wev++us ptiva@um ahpod*<br />

t6Znpawad<br />

Gkntrtim, wdi$ue- trahmtur, i~~a~hntuq vel fhifCW$$j teGdmt*-<br />

Hujus generis efi Gravitas, qua corpora tendunt ad cenwum ter-<br />

FE:; Vis Magnetica, qua krum petit magnetem 4 & Vis illa;,<br />

guScunqj fit, qua Planctx perpccuo retrahuntur a: motibus re&&<br />

e.eis, ils in lineis. curvjs revol.vi cogu.ntur. Lap&in funda, circuma&us9


DEFINI-<br />

T 1 o N E 3.. DEFINITIO -VI*<br />

yis ccntripeta ~w&~sA~~o?u~~ eJ mp$tira +$dem mdjop Qfmi@or<br />

pro E$&& caBf& &wzpropaganhs a centroper re$@@~s zyJ C2rcf~h<br />

Ut vis Magnetica pro mole magnetis vel intenhne Virtueis major*<br />

jn tmo magnete, minor in al’io.<br />

DEFINITIO<br />

VII..<br />

]yjs. ~e~j&petd @pntitas Accehatrix e$ $Ju’s~ WefffHrd ~eh+Uti~<br />

proportional& paw d&to ternlore genevd$-<br />

T&i Virtus magnetis ejufdem major irk minori difi+ia, lnhor<br />

in majori : vel vis, Gravitans major & (ut itn<br />

dicam) Pondus Srinnotefcit femper .per.vim ipfi con trariam;.& x-.<br />

qualem, qua dekenfhs corporis impediri pot&.<br />

E-l&X virium quanri~ates:brevitaeis gratis -~~omh,re licet: V&4<br />

. mocrices, accelerakces, &abfolutas; SE difiinQipnis gratis rcferre ad<br />

Gorporwxnaum petencia,ad8corprJrum.Loca,& ad.Ce;tl trurn virium:<br />

. nimirum vim motricem ad-Corpus, tanquam cunatum 8r: propenfio-<br />

33em totius in centrum cx. propenfionibus omnih partium compofitam<br />

5 8~ vim aceelecatricem ad Locum corporis,,tanquam efficacirlm:<br />

quondam, de centro per 10~s: hgula in circuitu diffuUaam, ad movenda,<br />

wrpora qua in ipfis ,funt j vim autem abhlucam ad.C&~rrum, :tc2nquam<br />

cau,fi aligua ~pra3zIitumr ‘fine qua vircs morrices n,oll propagancur<br />

per reglones in cirfzuitu j five caufa illa 4t corpus aliquad<br />

-wxrale .(qUale . * Cft h4qpes in cenb~o vis, magnctic,~, v,cl Terra in<br />

XxntrD;~


centro vis gravitantis) five aIia aliqua qw non apparet. Mathe- DEFINf..<br />

maticus duntaxat efi hit conceptus. Nam viriwm caufas 8-z fedes phy- TJONEH<br />

&as jam non expendo.<br />

Efi igitur vis acceleratrix ad vim motricem ut celeritas ad mo-<br />

*urn. Oritur enim quantitas motus ex ceIeritatc du&a in quarktatem<br />

materiz, & vis morrix ex vi acceleratrice d&a in quantita..<br />

tern ejufdem mater&. Nam fumma atiionum vis acceleratricis in<br />

Gngulas corporis particulas 41 vis motrix totius. Unde juxta<br />

fuperficiem ‘rerrae, ubi gravitas acceleratrix 53.1 vis gravitans in<br />

corporibus univerfis eadem eft, gravitas matrix feu pondus efi UC<br />

corpus : at G in regiones afcendatur ubi gravitas acceleratrix fit minor,<br />

pondus pariter minuerur J eritque iemper ut corpus in<br />

gravitatem acceleratricem duBurn. Sic in regionibus ubi gravitas<br />

acceleratrix duplo minor efiJ pondus corporis duplo vel triplo<br />

minoris erit quadruple vel kxtuplo minus.<br />

Porro attra&iones & impulfils eodem i’enfi.1 acceleratrices & mo-<br />

Wices nomino, Votes autem Attraeionis, Impullus, vel Propen-<br />

Gonis cujufcunque in centrum J indiEerenter & pro fe mutuo promikue<br />

ufurpo j has vires non Phyfke fed Mathematice tantum con-<br />

Gderando. Unde caveat, le&orJ ne per hujufmodi votes cogitet me<br />

ipeciem vel moduma&ionis caufimve aut rationem Phyficam aliaubi<br />

dkfinire, vel cencris (qux fimt pun&a Mathematics) vires<br />

vere & Phyfice tribuere; ii forte,nut centra trahere, aut vires ccnw<br />

trorum effe dixero.<br />

Si40lhM2;<br />

HaLtenus votes minus notasJ quo fenfi~ in kquentibus accipiendz<br />

fint, explicare vifiun efi. Nam Te.mpusJ Spatium, Locus<br />

& Motum, UC omnibus notiij[ima,non definio;Notandum tamen, quad,<br />

swlgus quan titates hake non aliter quam; ex’ relaeione ad kniibiljaconcipiar.<br />

Et inde oriuntur prajudicia qwdam, quibus rollendisf<br />

convenir eafdem in abdlblutas & relarivas, veras &, apparences, mathematicas<br />

& vulgares Gfiingui.<br />

1. ~empus’Abfolutu~~, verumJ & mathcmaticumJ in fe & mturar<br />

-, Kia abfq;. relatione ad externum quodvis9. zquabiliter fluit, alioq;,<br />

.nomine dicitur Duracio : Rclativum, apparens, & vulgare elZ kniibilis,<br />

82 externa qwcvis Durationis per ~inotum menftira ( CXI accurata<br />

&Xl irwquabilis) qua’ vUl.gus ,vice veri ten2p.oris uci$u~* j kit Hwa,.,<br />

Dies,J McnfisJ Annw. .<br />

n1, spa-


I; ~1-31ifEi NATURALIS<br />

n; !‘r t:r. II, ~~~~~~~~~~~~ k~;3~*til~~r~$~,<br />

na~~a hila a’:~k~uc relationc ad externum<br />

‘i Y 0:. I* 1. q[*~J~j\~i~, fk[$l pcf fi;LliieE liI!lil3l.C L&c immctblli: : Rd;ltiVLll~ di &a&ii<br />

j~ujus ~l~f-~~~~~i~~ ~CLI dli]ltJilliCl ~li,IJl!“ocC mub;iis, qUtl: a fenilbus IICJftr&<br />

pc; fitwn lilUlY1 ::,J CO~FO~,I ddinitur, & 3 vulgo pra f-patio immobili<br />

ulurp:ztur : uti dinlcniio fpatii iinbterranci, aerei ~1 cdef&s<br />

&fiJ$l per iitum iiwn 3d Terram. Edem iilnt fpatium abfolutum<br />

Cq rc~&~, @xie k magnicudinc; fed non permanent idem km*<br />

per nuLiw3. Nam ii Terra, verbi gratis, movetur j fpatium Aerb<br />

~~oi~ri, quad relative & refpefiu Terra: ikmper manct idem, nunc<br />

Cric 1lfla p-s @xtii abfoluti ii2 quain Am rraniit, Irum ah pars ejus-5<br />

& CL athlucc mutabirur perpetuos<br />

111. LOCUS efi pars fpaciiqnam corpus cxcupat,eitq; pro ratiane<br />

[patii vel A~folu~us vel Relarivus. Pars, inquam, fpatlt j non Sitas<br />

corporis, vcl Superlicks ambicns. Nam hlidorum zqualium<br />

3zquales fimper iilnt loci; Superficies autetn ab diflimilitwdinerPe<br />

fifiurarum ut plurimum insquales ki‘uct j Sicus vero pruprie Joquendo.quantitaccm<br />

non habent, neq; cam funt laca quam affe&ianes<br />

lUCOIW21. hIotus totius idem eit cum fimma motul-r~~ partiu~m,<br />

~XJC eit, tranilatio rotius dc fro loco eadem eit cum rumma tranflationum<br />

partium de Iocisihis; adeoq; locus.totius idem cum fimma<br />

locoruni partium, & propterea internus & in corpore tot0.<br />

IV. hiorus Abfolutus efi tranflatio corporis tie loco abfolutoin<br />

locrrtn abfolutum, Relativus de relative in relativum. Sic in navi<br />

qun: velis pailis fertur, relativus corporis Locus 893 navigii regio illa<br />

in qua corpus verfitur, ku cavitatis tocius pars illa quam corpus<br />

implet, quzq; adeo movctur una cum navi: & Qies relativa efi<br />

permanfio corporis in eadem illa navis regione vel partc cavitatis.<br />

At quies Vera efi permanfio corporis in eadem partc +atii<br />

illius immoti in qua navis ipl3 una cum cavitate fia & contentis<br />

univcrfis movetur. Unde fi Terravere quiefcit, corpus quad ~eIative<br />

quiefcit in navi, movcbitur vere & abfolure ea cumvelocitate<br />

qua navis movetur in Terra. Sin Terra etiam movetur j orietmr<br />

verus 8-z abfolutus corporis motus, partim ex Terra, motu. vero in)<br />

fpatio immoto, partim ex navis motu relativo inTerra: & fi cOrr8<br />

pus etiam movetur relative in navi j orierur verus ejus motus, partim<br />

cx ver0 mOtuTerra in fpatio immoto, partim ex relativis moW _.<br />

tibus tum navis in Terra, turn corporis in navi j & ex his motibus, .<br />

relativis orietwr corporis motus relativus in Terra, Utfi Tcrrx pxuz<br />

illa, ubi navis verfatur, movearur vere in orientem cum velocitate<br />

partium IooI0 j & velis ventoqj feratur navis in occidentem cum<br />

velocitate partium decem j Nauta autem amMet in navi orientem


PRINCIPIil Evl-i%THEhdki~IC,A., 7<br />

eatem’verfus cum velociratis parte ma : mo!7ebitur Nauta vere & DnFl Nlr<br />

&folute in fpatio immoto CUIII velocitacis partibus I0001 in o- TIoNES.<br />

r&tern, St relative in rerra occidentem verfus cum velocitatis<br />

pi~ils~~s novem.<br />

Tern pus Abfolu turn a relative dihguitur in Aitronomia per 2.k<br />

quationem temporis vulgi. Inxquales enim iimt dies Naturales )<br />

qui vulgo tanquam Zquales pro m&~fura temporis habentur, Hanc<br />

inz:cyualitatem corrigunt A fl ronomi , ut ex veriore ternpore<br />

maw cdeitesb Pofibile efi, ut nullus fit motus 3equabilis quo<br />

Ternpus accurate menhretur. Accelerari tic: retardari poh~t motus<br />

omnes, fed fluxw temporis Abfoluti mutari nequic. Eadcm efi duratio<br />

feu perfeverantia exifientk rerum j five motus fine celeres, five:<br />

tar&, five nulli: proihde 11%~ a menfuris fuis knfibilibus merit0<br />

difiinguitur, & ex iifdem colligifur per aquationem Afironomic;im,<br />

Hujus autem zquationis in determinandis Phznomenis necefitas,<br />

cum per experimentum Horologii Ofcillatorii, turn etiam<br />

per eclipfes Satellicum Jovis evincirur.<br />

UC partium Temporis ordo efi immutabilis, fit etiam ordo partiumspatii.<br />

Moveahtur 11~ de locis fuis, or movebuntur (ut ita<br />

dicanl) de feipfis. Nam tempora & fpatia filnt hi ipfortlm ck<br />

Perurn omnium quafi Loca. In Tempore quoad ordinem fuccefionis;<br />

in Spatio quoad ordinem fitus locantur univerh De illorum<br />

eirentia efi ut fmt Loca: & loca primaria moveri abfurdum<br />

efi, Hz funt igitur abf’blutaLoca; Sr ikkz tranilationes de hislocis<br />

hnt abfoluti Motus.<br />

Verum quoniam kc Spatii partes videri nequeunt, s( ab invieem<br />

per fenfils noitros diltingui; earum vice adhibemus mcnfuras<br />

6dibiles. Ex pofitionibus enim & diitantiis rerum a corpore aliquo,<br />

quod fpe&amus ut immobile, definimus loca univerfa: deinde<br />

etiam 8t omnes motus xftimamus cum refpettu ad przdiaa loca,<br />

quatenus corpora ab iifdem transfcrri concipimus. Sic vice loco;<br />

rum & motuum abfolutorum relativis utimur ; ncc incommode in<br />

rebus humanis : in Philofophicis autem abfhhendum eCt a fenfibus,<br />

Fieri etenim pore& mt nLillum revera quiefcat corpus,ad q~odioca<br />

motufque rcferantur.<br />

Difiinguuntur autem (X&es Sr Motus abfoluti & relativi ab invicem<br />

per Proprietates fuss & Caufis 6r EEe&us. Qietis proprietas<br />

4, quod corpora vere quiefcentia quiefcunt inter fk Idcoquc<br />

turn pofibilc fit, ut co‘rpus aliquod in regionibus Fixarw9 aut longe<br />

ultra, quiefcat abrolute; fciri autem non poflir cx firu corporum<br />

ad. invicem h regionibus noitris, Irorumne aliquod ad longin-<br />

qtaum


8 1)l[-IILosoPwI& NATURALIS<br />

DEFl@:t-<br />

qwm illrId &tarn pofitionem f&vet necne ; quies-Vera ex IhorUlD<br />

-r10NE5 1 fitu inter k dehiri nequic.<br />

Mows propriccas eft, quod partes, quze datas i‘ervant pofitiones<br />

ad rota, participant motes eorundem totorum. T-4 am Gyrantium<br />

paws ounces conantur rcccdere ab axe motus, 82 Progredientium<br />

impetus oritur ex conjunC;t-0 impetu partium fingularum. Motis<br />

igik corporibus ambientibus, moventur qox in ambientibus ,relarive<br />

quidcunt. Et propterca motus verus & abfolutus definiri IXquit<br />

per tranflationefn e vicinia corporum, quz tanquam Quiekkncia<br />

fpe&antur. Debent enim corpora externa non folum tanquam quiefkentia<br />

fpe&ari, kd etiam vere quiefcere. Alioquin inch& on+<br />

nia I pram ter tranilationem e vicinia ambientium , participabunt<br />

etiam ambiencium motus veros; & ftiblata illa tranfiatione non<br />

vere quiefcent, Ted tanquam quiefcentia foltinimsdo @e&abuntur.<br />

Sunt enim ambientia ad inclufi, ue totius pars exterior ad<br />

partem interiorem, vel ut cortex ad nucleum. Moto autem corrice,<br />

nucleus etiam, abfq; tranflatione de vicinia corticis, ceu pars<br />

torius ~rnovetur.<br />

Przcedenti proprietati affinis efi,,quod mote *Loco movetur;utia<br />

Locatum : adeoque corpusl quod de loco moto movetur, particip?<br />

etiam loci fiui motam. Motus igitur omncs, qui de, locis nlotls<br />

Jiunt, fi.mt partes Colummodo motuum integrorum & abfolutorum :<br />

& mows omnis integer compo.nitur ex mow corporis. de loco lruo<br />

prima, & motu loci hujus de loco ho3 8z iic deinceps ; ufque dum<br />

I perveniatur ad locum i immotum , ut in exemplo Nautx fiupra me7<br />

porato. Wnde motus integri & abfoluti non nifi per loca immota<br />

de&hi poffif!t : &z propterea 110s ad loca immota, relatives ad IIIQbilia<br />

fupra retuli.. Loca autem immota non knt, nifi qua: onwia<br />

ab in&to in infinitum dams Servant pofitiones ad in&em ; atque<br />

adeo femper manent immota, fpatiumque confiituunt quad Immo~<br />

bifc appello.<br />

Caufz:,. quibws motus veri & relativi difiinguuntur ab invicem,<br />

ki,mt yires in corpora impreffz ad motum generandum. MOW<br />

.verus nek generatur net mutatur, nifi per vires in ipfim corpus mbtum<br />

impreffas : ac motus relatives generari & mutari potefi ably*<br />

,viribus impreffis in hoc corpus. SufXkit enim LK imprimantur in<br />

alla’ iblum corpora ad qu3: kit relatio, .ut iis’ ceclentibus mutetur<br />

relatio illa in jua hujk quies vel motus rehivus confifiit. Rur7<br />

,;Tum nwtns verus a viribus in corpus motum imprefis fernper mutrl+<br />

gur; at motus reIativus ab his vjribus non mutatur necefirio, Narn<br />

ii ezdcm vires in alia etianz corpora, ad qux: fit rchtio, .fic impri-<br />

Ill~IlW~


li?EP IN I- cur vex Mutant enim pofiriones fua.s ad; iwvickm ~f$U~ Qlarn 5%<br />

T 1.0 N L 6. iI1 vere quicfcentibu8) unaque cum. cazlis dcYa”ati Gjar~filclPa*~~t .~orurn~<br />

mot-s, & UC parees rWOlV~itir7II~ tBtCXUtII,<br />

‘gj-’ ec)pdm; acibus. reqL<br />

derc conantur. -<br />

jgi[ur q~~3flritatcs relativ& non hnt CS ipfz quanti.~W% q+laWDh3<br />

nomina prz fe fCrUt> fed earum menhrz ilk h&bif~s ~(l~~r~~a~<br />

errantes) quibus vulgus loco quantiratum. rncnfu;~~aru,n~~u,~l~iE~. AC*<br />

fi ex ufu definiendaz funt verborum fignifieationc:s; pep nornina. illa<br />

Temporis, Spas& Loci & Motus proprie i~ntelligefid~; erw;.1$3.3+<br />

menfurs j & firm0 eriE iilColens & pure Machenlatic~~s’3 fi; qu~n@itaf;es<br />

menfurataz hit inrelligantur. &&da vim inf&un$~ &cris<br />

kiteris, qui votes hafce de quantitatibw mcn;hr&s $$ imterpre-<br />

EantWr. Neque mi.nus contaminant Math&n & @~~~~‘~i‘ophiHlim,?+<br />

qui qL7antitates pveras cum ipfarum relaEioilEbW ~,.~nigarl-bus’~~~m,’<br />

.iitris confundunt. /’<br />

I_) :<br />

Notus quidem zeros corporum fingt.kru~m~, co&l?ofcere, 4%. abapparencibus<br />

a&u d”&riminare, difEGllimuSm : afi proptcrea quo&<br />

partes fpatii ilhs immobilis , in quo corpora vere moventur,~ noiz<br />

Incurrunt in ienfus. Caufa tamen non offs prorhs de@erata. wami<br />

hppetunt argumenta’, partim ex mo ti b us y3par&cibGs~ qui- fint<br />

motwm verorum differentiz, partim kx viribus ji7x ik~t’- -mo-<br />

%uum verorum cauGk & eEe&us. Ut G globi duo’, ad d’aram aBirtvicem<br />

diitantiam filo intercedente connexi, rev~hw~entur circa<br />

commune gravicatis ten trum j innotefcerer ex tenGone fili cBn$-~<br />

eus gfoborum recedendi ab axe mows, 8~ in& quahi-tas mw~:15<br />

circularis comp.utari poffet, Deindk fi vires quzlibet aqua-les ill”<br />

alcernas, globorum facies.ad motum cikcnlarem augendum vei minuendum<br />

fimul imprimerentur , innotefkerer ex a&3-a vel diminara<br />

fili tenaione augmentum vel decrementurn morus j 8-z i’nde tandem<br />

inveniri poffent facies globorum in quas vires imprimi dcberent%<br />

ait mow maxime augeretur;id&, facies pofiicze, five qux in rnok<br />

tu circulari fiquun tur. Cog@s autcm hciebus qua ieqnuntur,<br />

EC faciebus oppofitis qua? prazcedunt, cognofceretrnr determinaticr<br />

motus. In hunt modum inveniri kpoil”et & quantitas 8-z determinatio<br />

mows hujus circufaris in vacua, quovis inwnen~o, ubi nihif<br />

cxtaret externum & fenfibile quocum gl‘obi confetiri pofGznt. St<br />

jam con~fiitaerentur in fpatio. ill0 corpora aliqqa Ionginqua &larxr<br />

her G pofitionem fervantia, qualia tint, St&z Fix= +I regi&nibu,$<br />

Rofiris: kiri quidem non poffet ex relativa globorklti tranflationc<br />

inter corpora , utrum his an illis tribuandus eiret nlorus. At: &I<br />

atten-<br />

‘1


Roje&ilia perfeverant in mot&us fuis, nifi quatefluS a refifiencia<br />

aeris retardantur, & vi gravitatis impelluntur deorfumL<br />

&IS, cujus parres cohzrendo perpetuo rctrahunt kfc a moaibus<br />

re&ilineis, non ceffat rota& nifi quatenms aba acre retardatur.<br />

Majora autem Planetarum & Cometarum corpo!a ,motus fiuos &<br />

progrefivos 82 circulares in fpatiis minus refX:entlbus fXkos confkrvane<br />

diutius,<br />

&ltit&nern wotus proportionalem eJe vi motrici imprejk, &jerk<br />

$eimdtim hem rehb.8 quu vis ilu imprirnitur.<br />

Si vis aliqua motum quemvis generet j dupln duplum, tri la trG<br />

plutr~ generabic, five fimul & fern& five gradatim & fucce K WC impreffa<br />

fuerit. Et hit motus (quoniam in eandcm fkmper plngar~~!<br />

cum vi generatrice determinatur) ii corpus antea mo~ebatur~ moxui<br />

Fjus vel confpiranti additw, vel contrario f’ubducitur, vel obli-.<br />

1 quo. oblique adjicitur, & cum eo, ‘fecundurn utriu[que detcrmina;<br />

aonem componitur. ,


PR.Fi,NCIPTA MAT’HEItkRXXi; ‘P.<br />

gW3 illnd ha?c plana viri6uS:pNF BN pecpcmdic’ulariter, nimirum: ~~~~~<br />

p~aXIWn.p~ V~$JJ??,,& p1a.n~~ #‘G vi kzfl. ldeoqueii tollacur pia- Md-rus~<br />

n,mp&ut pondus ten&t filum; quo1jiam: filum fi&inendo pandus<br />

jam vicem przfiat plani. fublati, tend-etur illud eadem vi p N,<br />

qua planum a~%:: urgebatur. Unde tenfia. f3i hujus obliqui eric<br />

ad tenfionem. fili al.derius perpendicularis 5?1!, ut p N ad pH. Ideoque<br />

.fi pandusp fi:t: 3d pondus A in racione qu”e com,ponitur ex<br />

ra-ticm reciqroca minimarum diltantiarum filwwIr fuorum p N,<br />

AM a cencro rota?, & ratione dire&a p W ad p A?; pondera idem<br />

valebwr, ad rotam movendam, atque adeo fe mutucr f’kfiinebunt,<br />

Opt quilibet espesiri: poeelt,<br />

. Pandtrs ,auGemip,4 pianis illia duobus obliquis incumbens, rationem<br />

habet- cm~5 inter eocporis fiG facies internas : & inde vires cunei<br />

i?e lna.lleB iti!no~etiuat : u-tzpote cum vis; qua poff&us p urgec planum<br />

p-grit xl vim,. q uab idem oel gravim.re fiia vel i&u mallei impellitur<br />

fkcund.um lineam p H in piano, ut;p N and p H; atque-adviwqua<br />

urger plznurrp alterum p G,uc pN ad NH. Sed & vis Ccrcl-ilez per<br />

fimilem virium divifion4m ~oll.igit.ur j qui,ppe quz cuneus eit a ve-<br />

&e impw&rs. Ufus igirur Co.foll3G hujus~ la&lime pacet, & late<br />

patendo’ veritarem fuam” evir&; CUM pendeat ex jam dic%s Mechanica<br />

Eora ab Au&ori.bwdiverfimode demo&rata. Ex hike en.im<br />

facile derivantur vires Machinarum, quz ex Rotis, Tympanis,><br />

Trochleis, VeQibus, newis ten& & ponderibus dire&e vel. obllr<br />

que afcendentibus, cazterifque potentiis Mech-z&is1 compck ib=+<br />

lent, LIE I;t: -&es Terrdinum ad animalium o.fi movenda.<br />

COROLLARIUM<br />

@p&us motus qug colbgitur cdpiendo Jummam motuum fuEhum.<br />

ud eandem partem, & differeaztiam faEartim ad contrarias, nan<br />

mututur a6 a&one car~oruminter~e.<br />

Et&m a&i0 eique contraria rea&io zqUaleS funF per Legem 111,<br />

;ideoque per Legem II aqualesin motibus efficiunt mutationes verfus<br />

conrrarias partes. Ergo fi motus fiunt ad eandem partem ; quicquid<br />

additur motui corporis:fugientis, ikbducetur motui corporis<br />

infequentis fit, ut fumrna maneat eadem quz prius. Sin corporaob-,<br />

iiam cant j zqualis erit filbdu&io de motu ukufque, adeoqtie difYe- .<br />

rentia motutim fa&torum in contrarias partes manebit eadem.<br />

Ut fi corpus +hzricum A fit triplo majus corpore rphzrico &habeatque<br />

duas velocitatis partes j 8i: 13 kquatwr in eadem- rekta cum velocitatis<br />

III.


’t; p$--~~~Lo'~oPHX,E PJATURAHS: '<br />

,.j~~ohiAT’.b<br />

lociratis partibus decem, adcoquemotus ipfius A fit ad ~~~dturri ipfius 1<br />

51 VE B .U~ fex ad dccem : ponantur motus i&s effe partium i‘ex R, par- :<br />

.ti;m dccem, & [un~na erit: partium fkxdecim, l[n,corporum l@tur ’<br />

coucurfu, fi corpus A lucretur mows partcs tres vel quatuor vel<br />

quinque, corpusB amittet partes totidem, adeoque perget corpus<br />

A pot reflexionem cum parribus novem vel decem d udecrms ;<br />

& B cum part&us feptem vel kx vel quinque, exifiente limper fUm- ;<br />

lna partiunl kxdecim ut prius. Si corpus A lucretur partes noverm :<br />

vel decem vel undecim vel duodecim, adeoque progrediatur POficoncur[um<br />

cum partibus quindecim vel fexdecim vel fiprendecim!<br />

ve] o&odecim; corpus B, amitrendo tot partes quot Irf bcratup:<br />

vel cum una parte progredietur ‘aniiffrs partibus, novem, VH gu+<br />

efcet amiKo motu .fuo progrefivo partium decem, ‘vel CUIII unapar#Y<br />

te regredietur amiffo motu, fro & (ut ita dicam) ulia parte‘ ampbuss<br />

vel regredietur cum partibus duabus ,ob .detra&um motum’progref-*%<br />

fivum partium duodecim. Atque ita hrnrnz motuum confpirantium;<br />

If+r vel I&+-o, &diEerentia: contrariorum 17-18~ x8-2 fimpcr.<br />

erunt partium kxdecim, ut ante concurfum & reflexionem. ,w Cog&~<br />

tis autem motibus quibufcum corpora pofi refltxionem pergent, invenietur<br />

cujufquk velocitas, ponendo earn effe ad velocitatem ante<br />

reflexionem, tie motus poit efi ad motum ante. Ut in cafil ultimo, ubi..<br />

corporis A motus erat partium kx ante reflexionem & partium oElsodecim<br />

poitea, & velocitas partium duarum ante reflexionem 5 invenietur<br />

ejus velocitas partium kx pofi reflexionem, dicendo, UC<br />

motus partes fex ante reflexionem ad motus partes ohdecim pofi-:<br />

ea, ita velocitatis partes dwe ante reflexionem ad velocitatis partcs<br />

&x poftea.<br />

s<br />

Qod ii corpora vel non Sphzrica vel, diver& in refiis movenlia<br />

incidant in fe.mutuo oblique, & requirhtur eorum motus pofJ~ 1$2exionem;<br />

cognofcendus efi fi tus plani a quo corpora concurrentia tanguncur<br />

in pun&o concurfus : deiil corporis utriufque motws (per<br />

Coroh.) dihguendus efi in duos,. uuum huic plano perpendicuharem,<br />

alterum eidem parallelurn: motus autem paralleli, proptcr-<br />

.ea quad corpora agant in fk invicem fecundurn’ linean huic plana,<br />

perpend@arem, retineudi funt iidem pofi reflexionem ,atque antea;<br />

Srmorlbus perpendicularibuq mutationes xqu&s in parres con;,<br />

-trarks tribtienda fuht fit, ut fumma confpirantium & di@erentia<br />

contrariorum maneak eadem quaz prius. Ex hujufmodi rcflexioihs<br />

oriri cciam folent motus circulares corporum circa centra pro-<br />

aria. Sed 110s cafcls in fequentibus non confidero, &nimislongum<br />

d.lh omaia hut f@&antia demonfirarc.<br />

CC,ROL-


NCIPIA M THXMATICA.


IS pHILOSc=ll?HI~ -NATURALJS<br />

mutat fiaturn fuum i & reliquorum, quibufcum atiio illa non iaterccdit,<br />

commuue gravitatis centrum nihil inde patirur 5 difiantia<br />

aurem horum duorum cenrrorum dividirur a cornmuIli Corporum<br />

omnium centro in garres Cummis totalibus corporIrm Quorum<br />

iilnt celltra reciproce proportionales 5 adeoque centris. illis: duobus<br />

aatu[ll filum movendi vei auiefcendi krvantlbus, colmmune omniuul<br />

centrum krvat etiam itacum Gum : manifehm efP quad commune<br />

illud omnium centrum ob afii6nes binorum corporuln inter<br />

1~ Ilunquam mutat it atum hum quoad motum & quietem. In tali<br />

auiem fyfiemare aQiones omnes cprporum inter fe, VC~ inter bina.<br />

(unt corpora, veI ab a&ionibus inter bina comi>ofitZj 5 pro ,terea<br />

communi omnium centro mutationem in fiatu motes ejus ve r quictis<br />

nunquam inducunt. Qare cum centrum illud u$ corpora uon<br />

agLInt in fi invicem, be1 quiefcjt, vel in r&a aliqua progreditur uni*<br />

formicer j perget fdem , non ot&antibus corporum aktionibus~inter<br />

i’e, vel f&per quieicere, vel, kmper progredi uniformiter in dira-<br />

&urn j nifi a viribus in fyitema extrinfecus in1pre.G deturbctur de hoc.<br />

fiatu. Eflc ~~itur fyitetnatis corporum phiurn Lex eadem ~UZ COEporis<br />

folitarll, quoad perfeverantiam in tliatu motus vel q~let~s; MO,-.<br />

tus enim. progreflivus ku corporis folitarii feu fjtflematis corporum’<br />

ex mow centri gravitatis azitimari femper debet.<br />

COROLLARWM V.<br />

Corporum datoJdti0 incl5Jorum Gilem J&at mottos irtter Se, Jwf J&zthmz<br />

i&d g.Gefctit, &ye wbowcratusr idem z&form&r iti d&e&~~<br />

n bfqste m.otu circularL<br />

Nam diEerenti,?: motuum tendentium ad eandem parrcm, & fummz<br />

teudentium ad contrarias, ezdem funt hb irlitio in utroq; c&i (ex<br />

hyporhcii) & ex his hrnmis vel differeatiis oriuntur congre#& EC: impetus<br />

quibus corpora k mutuo,.feriwt~t. Ergo per Legetl~ I x ,~q+ua~es C-<br />

~unrcongreffu.um.effe~tus in LltrOqj caCu 3 & propterea alanabuntnlaminter<br />

kin uno cab aquaks moths inter fe inaltero. ldcm corn;;<br />

probatur experimenta luculento, Motuo omnes eodem m&o 1; 113~<br />

km in Navi, five ea quieht, five moveatur uniform iter ill d~re~um;<br />

CwOROLL ARI U&J VI.<br />

Si~oqQramfme~tfw q~O~odoCU'llrqjinterclk,~ a.wirit;u~- ~c~&?r~~~~~&<br />

bus ceq~dlib~sSecund~~~linenspuralle~us wgeanttir; pepgent oMwiH i<br />

sodem mdo mow& interJ&~ j cuirib~~ ii& non tf&t. inC;tdtd.<br />

Nana vires illr:aq,uakr (pro guantitatibus movendoru1;11 corpo-<br />

. 3m-n j


PRIN~CX~IA M.ATHE.bIATrc A. 1y<br />

rum) & fecundurn lincas parallelas .agendo, corpora omnia ,~quaIi- LEG ES<br />

cer (quoad velocitatem) lnovebunt perkgem I I, adeoque nunquam hl OT u s.<br />

mutabunt pditiones & motus eorum inter k.<br />

HaOenus principia tradidi a .Mathematicis recepta & experientia<br />

multiplici confirmata. Per Leges duas primas & Corollaria duo<br />

prima Gnlih~s invenit defcenfum Gravium efl”e .in duplieata ratiolIe<br />

temporis, 6r motum l?roje&itium fieri in Parabola j confpirante experientia,<br />

nifi quatenUS mot&S illi per aeris refiflentiam aliquantulum<br />

retardantur. Ab iikkm Legibus SC Corollariis pendent demonfirata<br />

de temporibus ofcillantium Pendulorum, hffragante Horologiorum<br />

experientia quotidiana. EX his iifdem .& Lege tertia<br />

Ckwi~o~hor~~s Wrennus Eques Auratus, &4annes JW’XZ~W S. T. 9,<br />

& ~Chz$ianz~s Htig&zls, hujus ztatis Geometrarum Facile principes,<br />

regulas congreifuum & reflexionum .duorum corporum feorfim<br />

invenerunt, & eodem fere tempore cum J’o&taze I&g&<br />

commynicarutit, inter fe (quoad has leges) omnino conlpirantes:<br />

& primus quidem WU$k dehde Wrennus A Hagenias inventurn<br />

prodidcrunt., Sed Sr: veritas comprobata efi a #?ww coram<br />

liegi~~ &c&ate per experimenturn .Penduiorum : .quod etiam<br />

CZ&?kus Muriottz~s libro integro exponere rnox digrratus cit. Vcrum,<br />

ut hoc experimenturn cum Theoriis ad amuflim congruat, habenda<br />

efi ratio cum refifientk aeris, turn etiam vis ElafticE concurrentium<br />

,corporum. Pendeane- corpora A, B filis parallelis &<br />

aqllalibus AC, BD, a centris C,D. His centris &intervailis dcfcribantur<br />

femicirculi E A F, GB H radiis CA, D B bifetii. Trahatur<br />

corpus A ad arcus E AF pun&urn quodvis R, & (rubduQo<br />

corpore B) demittatur inde, redeatque pofl unam ofcillatiorlem<br />

ad puntium K .Eft .W+e- ?E ~<br />

tardatio ex refiitentia acris.<br />

c! 5 _ ._., 3 xl<br />

Hujus R Vfiat ST pars quarta<br />

fita in media, ita fiilicet<br />

ut RS & TY aquentur, fitque<br />

RS ad STut 3 ad 2.<br />

Et ifta ST exhibebit retardationem<br />

in defcenfu at 5’ ad A<br />

quam proxime. .Reltituatur<br />

corpus B in locum iilum. Cadat corpus A de pun&o 5, ,& velocitas<br />

ejus in loco reflexionis R, abfque errore fenfibili, tanta eric ac<br />

DZ i?


- 20<br />

fi itI Vacua &diffet: de loco ?-. Exponatur if$tLlr haze vek~citclS j<br />

AxlohlhT*,<br />

per chordam arcus TA. &Jam velocitatem rend+ in pun&o i.n- 1<br />

SiVE<br />

cm0 ere ue c~~ordam arcus quem cadcndo dckripilt, Propofitio eB i<br />

efi Geomatris n&Jima.<br />

P0fi refkxionem perveniat corpus & ad (<br />

locum f, & corpus B ad lOC~1~~ b. Tollatur corpus B & invenia- /<br />

tur Iocus v; a quo fi corpus A demittatur 8~ pofi ullarn okiIlaGo- !<br />

nem redeat ad Iocum rJ fit st pars quarta ipfius ~-ZJ fita in mcdio, ;<br />

j,a videlicct ut r s & t ti xquentur ; & per Chord’am arcus 8 A’ cX- j<br />

ponatur velocitas quam corpus A proxime pofi rcflcxionem habuit:<br />

in JOCO A, Nam t erit locus ilk vcrus & corrcqlw, ad quem cot- j<br />

pIIs A, h]bIata aeris refiflentia, afccnderc dc+ulKk. Sim& me- 1<br />

thodo corrigcndus wit 10~~ k, ad quem corpus 23 afcendit, & .ixp- :<br />

velliendus locus I, ad quem corpus ifIud akcndere debuiffet in va- j<br />

CUO. HOC pa&o experiri licct omnia perinde ac fi in vacua CCUT- ;<br />

ftituti efemus. Tandem ducendum erit corpus A in chordam ar*- j<br />

cus TA (quz velociratem ejus exhibet) ut habeatur nmcus ejus ixr I<br />

loco A proxime ante rcflexionem -,<br />

deinde in chorclamr arcw, .gd, Tut: ;<br />

.habeatur mows ejus in loco A proxime pofi: reflexioncm. Et fit j<br />

corpus B ducendum cril: in chordam arcus BG, w habeatur mcltu-s I<br />

cjus proxime pofi reflexionem, Et fimili IFethodo, rlbi corpora duo 1<br />

ihul demittuntur de lock diverfis, invenrendi firnt marls utr.hfcX~ j<br />

tam ante, quam poi2: reflexionem i & turn demum confercndi fi~nr i<br />

motus inter fi & colligendi efi%&~~s reflexionis. Hoc modo in 1<br />

Bcndnlis ped~m deccm rem rentandol idque in corporibus tslm i<br />

in~qualibus quam zrqualibus, & facicndo ut corpora de iatcrvallis :<br />

ampliffhis, puta pedum oQo vcl duodecim vel fbxdccim, co~~ctlrrc- /<br />

rent j rcpelri fernper fine errore triwn digitorum in xncnkris, 1.1bi i<br />

corpora fibi mutuo dire&e occurrcbant, ELIOT zqualcs erant mutaM j<br />

tio!les motuum corporibas in partes conerarlas iXlat32, atque XI&J :<br />

quod a&o & rea&io timper<br />

i<br />

erant aquales, Wt ii corpus<br />

i 1<br />

.A incidebat ily corpus 23 cam<br />

i<br />

novem partibus niorus, Sz a-<br />

b<br />

1<br />

nGfis ieptcm partibus perge-<br />

1<br />

I<br />

batpoft reflexionem cum du-<br />

i<br />

abus; corpusB refiliebat cum ,<br />

\<br />

partibus ifiis kptem. Si corpora<br />

obviam ibant A calm i<br />

e<br />

dwdecinl parthus si: 13 cum fix, St re&bat A culll duabub ;, rcdiq j


PRINCIPIIA MATWEMATIcA. z.1<br />

nihil: fubducantur alia: partes dub, & fiet motus dwarum partium<br />

in plagam contrariam : k Gc de motu corporis B partium fex Tub- $oE:ii<br />

ducendo partes quatuordecim, fient partes o&o in plagam contrariam.<br />

Qlod f I car p ora ibanc ad eandam plagam, A velocius cum<br />

partibus quatuordecim, Sr B tardius cum pa’rribus quinque, & po&<br />

reflexionem pergebat Scum quinque part&us j pergebat B cum quaruordecim,<br />

fafla tranflatione partium novem de A in B. EC iic<br />

in reliquis. A congrefh Sz: collifione corporum nunquam mutabatur<br />

quantitas mows, qulr: ex fi.mIma motuum confpirantium &<br />

differentia contrariorum colligebatur. Nam errorem digiti unlius<br />

& alterius in menfuris tribuerim difficultati peragendi fingula<br />

fatis accurate. Difficile erat, turn pendula fimul denhere fit, u.t<br />

corpora in k muruo impingerent in loco infimo A Bj cum loca sJ<br />

k notare, ad qu3: corpora afcendebant pofi concurfum. Sed & in<br />

ipfis pilis inazqualis partium denfitas, & textura aliis de cauh irreguIaris,<br />

errores inducebant.<br />

Porro nequis objiciat Regulam, ad quam probandam inventum<br />

efi hoc experimenturn, .prsfupponere corpora vel abiblute dura<br />

effe, vel faltem perfeae elafiica, cujufmodi nulla reperiuntur in<br />

compofitionibus naturalibus; addo quod Experimenta jam defiripta<br />

fkcedunt in corporibus mollibus azque ac in duris, nimirum a<br />

conditione duritiei neutiquam pendentia. Nam ii Regula illa in<br />

corporibus non perfeLte duris tentanda ef?, debebit ~oolummodo<br />

reflexio minui in cerca proportione pro quantitate vis Elafiic3e. In<br />

Theoria Wren& & Htigenit corpora abfolute dura redeunt ab invicem<br />

cum velocitate congreffis, Certius id affirmabitur de perfeh<br />

Elafiicis. In imperfefie Elafiicis velocitas reditus minuenda eft iimu1<br />

cum vi Elafiica; propterea quad vis illa, (nifi ubi partes corporum<br />

ex congreffh lxdunturl, vel extenfionem-aliqualem quail fu.b<br />

malleo paeiuntur,) certa ac determinata fit (quantum kntio) faciatque<br />

corpora rcdire ab invicem cum velohte relativa, qua: fit ad<br />

relativam velocitatem concurfis in data ratione. Id in pilia ex lana<br />

ar&e conglomerata & fortiter confiri&a fit tentavi. Primum demittendo<br />

Pendula & menfirando reflexionem, inveni quanticatem vis<br />

Elaff icze j deinde per hanc vim determinavi reflexiones in aliis cafibus<br />

concurfium, & refpondebant Experimenta. Redibant femper<br />

pilz ah invicem cum velocitate relativa, quz effct ad velocitatem<br />

xelativam concur&s ut p ad 9 circiter. Eadem fere cum velocitate<br />

redibant pilz ex chalybe: alia: ex fubere cum Fjaulo minore: in.vi-<br />

Ereis autem proportio erat I 5 ad 16 circitcr. Atque hoc pa&o Lex<br />

tertia quoad i&xsI~ & reflexiones pe.r Theoriana, comprobn$a~ef&. ~LKE<br />

cum exyerientia plane congruk In


2.2 P.H;I-L~s~PE-~I& h~ATu.~M.xs<br />

A X’#I 0 N AK A, ;Tn!A ttrx&ienibus rem dk ~brevirer ofiendo. Corparibus :duobus<br />

SIVE quib&vis A, B ik mutuo trahentibus , .concipc obtk~ulum quodvis<br />

intcrponi quo congreffk eorum impediatur. Si cor.p~ a1terutr.u.m<br />

A magis trahitur verfus corpus alterum B, ~LWYI illud alterum 23<br />

in prius A, obfiaculuni magis urgebitur preflione cor.poris .A quam<br />

.preilione corporis B j prpindeque non manebic .in squilibrio. .PIXY-<br />

,valebit preflio fortior, faCetqae ut fjdktna corporum duorum :&<br />

obfiaculi moveaturin dir&-urn in partes verfils,B, motuque in fpatiis<br />

liberis ikmper accclerato abeat in infinitum, Qod efi abfurdum 6r<br />

Legi Frimz,contrarium, Nam ‘per Legem .primam debebit .i’yRema<br />

.perfeverare in ffatu fuo quiefcendi vel movendi uniformiter .in dire&.un,<br />

proindeque .corpora SXldiEer urgeburit obfiaculum, ;Ik idckco<br />

aqualker trahentur in invicem. Tentavi hoc in Magne!te &<br />

Ferro. Si h~c in vafcfculis .propriis 6$e contingentibus karfim po-<br />

Gta, ‘$1 aqua !fiagnante juxta fl uitent j neutrum propellet alterum,<br />

fed zqualirate attra&ionis utrinque luRinebul-rt tcon;ltus in :fe 6mu-<br />

XIIOS, ac tandem in zquilibrio con.~it~t~,.q~lie~ent.<br />

&Sic etiam .Sr.avitas inter Terram &,ejus p-a~~es, mutW:efi. Secetur<br />

Terra %‘1 piano quovis E G in p,artes dual EGE & +EGf:<br />

s& zqualia.erunt ~harum polldcra in .fe muwo:<br />

Nam ii piano alio dH.zI< quod priori<br />

2YZ G .paralleIum fit, pars major E’GI:fecetur<br />

in partes duas EGKW & HK.1,<br />

quarum NKiT zqualis iir parti prius zib- J?<br />

lXffz E FG: mnifefium efi quad pars<br />

,media E.GKN pondere proprio in new-<br />

*tram partium extremarnm .propendebit,<br />

$ed inter utramque in equilibria, ‘ut ita<br />

&am, fiufpentletur, &,quiefcet. ‘Patts autem extrcma iFil..K$$oto<br />

fro myondere &umber .in partem mcdiam-, 8.z .urgebit illam in<br />

.yartem altera,m extrcnwlz EGcF;. ideoque vis qua p&urn<br />

;UK.I & UGKN ~rurnrna 22 GI tcndit verfks parcem ‘ter&m<br />

E’G 1;; zqualis efi podcri partis .HK& -id eII ponderi,paks ,QWftiaE<br />

E GjR. ;Et rpropterwpondera partium .duarum EGI, &G&’<br />

Iin k ‘mutuo knt rrqua.Iia, uti volui ofiendere. Et nifi pondera -,I&I<br />

zx$ualia+&‘knt, ‘Terra,tota in libero 3zthere YIu.iraa~s~pond-c%ri :rnz$&<br />

cederet, 8r ab*eo fLlgiendo abiret in infinitum,<br />

Ut corpora in concurfu SC reflexione idem pollent, quor,um A&<br />

locitates filnt reciproce ut vires in-Cm: $c ;in “movendis ItifIru:-<br />

mentis ,Mechanicis agentia idem pollens & eonatibus contrariie :fk<br />

2nutuo ftiitinent, quorum veIocitate6 ‘fecundum &tcrminatidwn<br />

vil;ium


fuNCl[PIA &dWr"HE-MATIcA. 23<br />

viiium afiimat zz> Cunt reciproce ut vires. Sk pond-era aquipolleYX<br />

a& movenda brachis Libras, qu”: ofkillante Libra funt reciproce ut<br />

eorum velocitates furi?lm Bs: deorfum : hoc efi, pondera, G re&a<br />

afiendunt & dehzndunt, zquipollent, qw fiint reciproce. IX pun-<br />

&own a quibus fhfpenduntur difiantiz ab axe Librzj fin- plank<br />

obliquis aliifve admotis obhculis impedha afcendunt’ vet d&cendunt<br />

oblique, aequipollent qua: kiln t reciprpce ut afcenfus & detienfus,<br />

quarenus hAi fecundurn perpendiculum : id adeo 06 dete-rminarionem<br />

gravitatis deorfum. Similiter in Trocblea fiu Polyfpafio<br />

vis manus hnem diretie trahentis, quz. fit ad pond-us’ vel~dke-&<br />

vel oblique afcendens ut velocitas akenfus perpendicularis ad velocitatem<br />

manus funem trahentis, Winebit pondus. In Horologiis<br />

& fimilibus infirumcntis, qw ex rotulis commifis conltru&a<br />

itint,, ,vires. coatrark ad motum rotularum promovendum &- impediendum,<br />

fi fht reciproce ut velocitates partium rotularum in q.oas<br />

imprimuntur, ftifiincbunt fe mutuo. Vis Cochlea ad premendum.<br />

corpus efi ad vim manus manubrium circumagentis, ut circularis<br />

velocitas manubrii ea, in pzwe ubi a rnan~~ urgerur> ad velocitatem<br />

progrefivam cochlea verlrus corpus preffum. Vires quibus Cuneus<br />

urget partes d.uss ligni fifi..func. ad. vim..mallei..ia.cur~eum, ut<br />

progreffus cunei fecundurn determinationem vis a malleo in ipfum<br />

imprefk, ad velocitarem qua partes ligni cedunr cuneo, fecundum<br />

lineas faciebus cunei perpendiculares. Et par eft, ratio Machar<br />

rum omnium.<br />

Harum efkacia & ufis in eb 2&.~ confifiit, ut diminuendovelocitateni<br />

augeanius vim, SC contra : Unde folvitur in omni aptorum<br />

infirumentorum genere Problema, Zrattim. pondz~s h&la ui naoven-<br />

&, aliamve datam refifkentiam vi ,daca filperar;ldi. Nam ii-Ma-<br />

cliinz ‘ita formen tur, ut velocita tes Rgentis ik Refi’ff’entis hit reciproce<br />

ut vires; Agens refi’Rkntiam fiTff inebic : & maj.ori cumi velocitatum<br />

,di@aritate @andem vincet.. Cerce ii tam& fit: mehaith.~m<br />

diljjaritas, UC vincatur etiam reGfientia60mnis, qi~~ tam ex contiguorum<br />

& inter re labentium corporum attritione, quam ek conrinuorum<br />

.& ab invicem fiparandblwm. cohafione &r: elevaa~do’rum<br />

ponderibus oriri iolet j fiiperata omni ea re.fiBenria., Visa: r,edundans<br />

accelerationem motes fib,i psoportionalem, pasti.m in part&<br />

bus machinze, partim in corpore refifiente * producet. Gcterum.<br />

Mechanicam trakktre non efl hujus infiiruti. Hike volui tan-.<br />

turn .ofiendere z quam late pateat quamque certa fit Lex tercia.<br />

MO tus. Nam fi &I+wtur A.gentis a&i0 ex ejus. vi & velocitat.e


24<br />

~~ILOSOPMI&<br />

NATURALIS<br />

DE hloru tare conjunQirn ; & fiditer Refifientis w&-i0 aflzitpetur conjunco<br />

Rr~ x~ M &in1 ex ejus partium Gngularum velocitatibus & virhx3 retiftedi<br />

ab earurn artririone, cchfione, pondere, & acceleratione or&<br />

undis; erunr aQio L? rca&io~ in omni infirumentorum ufu,<br />

{ibi illvice hnper ZXJlI3lCS. Et quatenus a&o propagatur per<br />

infirumentLm1 Sr: ulrimo imprimitur in. corpus 0mne refiiten&<br />

ejus uI&na dcterminatio determination1 rea&ionis Gmper erit<br />

conrraria.<br />

DE<br />

.L E n/T M A .I.<br />

Umtitdtes, ut & pantitatum rationes, qzw ad aqualitatem<br />

tempore pornis finito conzanter tendtint, & an~efiiaem tempo-<br />

.ris ills propius ad invicem a~cedunt quam pro dutn guawis diffe=tia,<br />

junt ultimo qi2ale.s.<br />

Si negas; fiant ukim6 inequales, & fit earum nlrima differentia<br />

59. Er o nequeunt proyius ad xqualitatem accedere quam :pre<br />

data di ttg erentia 23: contra hypothefin, .)


“.-<br />

.’<br />

‘\<br />

*-”<br />

--


DZ MOTIJ centium arcuum ab, bc, cd, ,&c. comprehenditur, coincidit ultimo<br />

culn Figura curvilinea.<br />

c0r02. 3, Ut & Figura reQiIinea circumfcripta qU= tangcntibus<br />

eorundcmx arcuum comprehenditur,<br />

COUO~. 4* Et propterea ha Figura ultimz (quoad peri?etros u cE,)<br />

non fu‘wnt r&&lincz, fed reQilinearum limites curvibel*<br />

CORPORUM<br />

Et&Gffl ut fynh parallelogramma fingula ad fingula, -ita (componendo)<br />

fit. fumma omnium ad fummam omnium, & ita Figure ad<br />

Figurtim 5 exifiente nlmirum Figura priore(per Lemma I 11x) ad furnmam<br />

priorem, & Figura pofierlke ad fummzim pofieriokm ih rationc<br />

zquajitatis. $.2& E. 2).<br />

Coral. _ Hint fi dua- cujufknque generis quantitates in eandem<br />

partium numerum utcunque dividantur; & partes iIke, ubi nume~u~<br />

earum -awge,tur & magnitude &&ill&w in infinitunl,. d.atam ofb&<br />

neant rationem ad $vicem, prima ad primam, fecunda ad kcuadam,<br />

czterz:que fuo ordme ad cxteras: erunt tota ad invicem in eadem<br />

illa dara ratione. .Nam G in Lemmatis hujus Figuris fumantwar pafalleIa-


PRIN~IPIA<br />

A/iATWEhht,'~~~~.<br />

rallelogramma inter fe ut partes, filrnrnx partium fcmper erunt ut<br />

fimm;r: parallelogrammorur J 3 - atque adeo, ~1f.6 pxtium & IJarallelogrammoryn<br />

numerus augetur 8-z magnirudo diminuit-lr in inhniturn9<br />

in ultlma ratlone parakzlogrammi ad parallelogrammum, id<br />

efi (per bypdlefil~] in ultima ratione partis ad par&em,<br />

"7<br />

LIHZr.<br />

P ,< r !! v $.<br />

.LEMhlA v.<br />

L E M M A<br />

VI.<br />

$i. arcus quilibet poj.Gone datm A B J&bbm<br />

tendatur chorda A B, & ie punk% A<br />

&quo A, in wedio cum~atme contimce,<br />

taflgatur a re@a uhngue prod&a<br />

A D j deiw puni3a A, B ad invicem R<br />

accedant & cot’ant ; dice quad angulus<br />

g A I), jhb chorda & tangente conten-<br />

PUS, minuetuty in h&&urn & ultimo e-<br />

wme$ceL<br />

T<br />

Nam fi angulus ille non evanefcit, continebit arcus AB cum tangente<br />

Aa a~guhm r~&ilineo zqualem, & propterea curvatura ad<br />

ad pull&urn A non erlt continua, contra hypotllefin-<br />

L E M M A<br />

VH.<br />

@dem.po&tis j dice quad ultima ratio UPCUS, chord&, & tangntk<br />

ad invicem efl ratio squalitatis.<br />

Nam dum pun&urn B ad pullEturn A accedit, inteltigantur emper<br />

A.23 & .JTI ad pun&a longinqua b ac d produci, & fic?ntl. B 23<br />

parallela agatur b d. Sitque ‘arcus Ab fernper Iimilis ar+r AB.<br />

Et pun&is ,d, B coeuntibus , angulus dAb, per Lemma fi~pe’riw<br />

yanefcet ; adeoque retiz kmper finitze Ab, &‘arcus in,terniedius<br />

Ab coincident, & propterea zxpaies erun % Unde & hifce<br />

.kmper proportionales re&z AB, AI>, & arcus intermedius AB<br />

E2<br />

en-


23 m-W.LW3PHI.A NATURA.LIS<br />

evanefcent, & rationenl ultimam habebunt ~qualitatitk L&f%.B*<br />

Coral. 1. Uncle ii per B ducatur tangenti parallela B F, r&am<br />

quamvis AF per ~4 tranfe--<br />

untem perpetua kcans in FJ<br />

hze:c B .F ul time ad arcum e;<br />

vanefcentem A B rationem<br />

habebit szqualitatis, eo quad<br />

complete paraUe]ogrammo k!FBr) rationem femper habet-Equal<br />

litatis ad AD.<br />

Coral. 2. Et di per B & A dacantur plures re&x BE, B2>, AJ’.‘.<br />

JG, fkcantes tangentem AZ) & ipfius parallelam B%lj ratio u]tima<br />

abfcifikxm omnium A”D, A’E, B.F, B @, chordsque 8-z arcus<br />

AB ad jnvicem erit satio azqualitatis.<br />

Coral. 3. Et propterea; 11% omnes linex, in omni d,e rationihs ~14<br />

timis argumcntatione, pro k invicem ufurpari pofiw.:<br />

G E M M A VIIE. . .<br />

Nam dum pun&ml I3 ad pun&urn A<br />

xcedit, intellig5tur femper ABj A3), AR<br />

ad pun&a longinqun 6, d & r produci,<br />

ipfiqwe 112) parallela agi r b d, & arcui<br />

AB fimilis femper fit arcus Ab. Et coeu&bus<br />

pun&is A, B, angulus. b Ad. evanefcet,<br />

& . ropterea triangula tria femper.<br />

finiea r,A Ip ; r A6, r&d coincident, funtque.<br />

eo, nomine fimilia & xqualia. Unde<br />

$t hi&% kmpec fimilia & propoctionalia<br />

R AB , R A B, R,.dZl fient ultimo~ fibi’<br />

kwicem.fimilia & zqualia. ,$Z$ E. 2).<br />

COW& ‘Et hint triangula illaj,in omni de rationibw<br />

~cntadone,i pro k invkem~ ufurpari pofint,.<br />

‘,<br />

uleimis arg+


L E M M A<br />

si. re& A E & CWUGJ A B C pojtione ddtg fe mutclo .[ecenGn<br />

aqulo ddto A, & ad retiiam Uam in alio data angulo ordina-<br />

@VZ applicentw B D, C E, czwv~ occurrentes ia B, C; dein<br />

pm&a R, C /&rml accedant ad punEum A : dice quod are& tridngulorm<br />

A-B D, A C E ermk<br />

ratione Iatwum.<br />

Etenim dum pun&a B, C accedunt<br />

.,ad pun&urn A, inteIligatur<br />

femper Aa> produci ad pun&a longinqua<br />

d & e, ut fint Ad, Ae ipfis<br />

AfD, AE proportionales, & e-<br />

rigantur ordinatx ddi, ec ordinatis<br />

‘I)B, E C parallels qua: occurrant<br />

ipfis A B, A C produQis in<br />

b & c. Duci intelligatur, turn curva<br />

Abe ipfi AB C Gmilis, turn re&a<br />

Ag, qua;: tangat curvam utramque<br />

in A, SS: f&et ,ordinatim applicatas<br />

2) B, E C, db, e c in F, G, f, g.<br />

Tuna manente longitudine Ae co&ant pun&a S; C cum pun&o Aj -<br />

& angulo c Ag evanefcente, coincident area curviline;E: Abd, Ace,<br />

cum re&ilineis Af d, Age: adeoque (per Lemma v) erunt in dudicata<br />

ratione later-urn Ad, Ae : Sed his areis proportionales f&-nper*<br />

fiint arex AB 9, ACE, & his lateribus lateraAZ3, AE. Ergo &<br />

are% AB 23, ACE fknt ultimo in duplicata rarione laterum AB,<br />

AE. g&?L=D.<br />

LEMMA X.<br />

IX.<br />

F, I B l%R<br />

i?iIMVSv<br />

Exponanrur tempera per lineas A4i3; AE9 & velocitates genitz<br />

per ordinatas, ‘23 B, E Cj St fpaeia. his velocitatibus defcripta, eru\nt<br />

ut area A B 2>, ACE his ordinatis defcripcz, hoc efi, ipfo mows.<br />

init; (gr Lemma TX) in dwglicata ratione temposum ,kZI, AE,.<br />

’ ** ft2m.d


‘~H~I~~$X~W-XE N A URALfS<br />

3”<br />

19 E ifI0.r v<br />

cOrO/8 T. EC ljinc facile colligitur>- quod corporunl fim-$s fin&<br />

cunpgR V :.I liLl\ll Figurarum partes temporibus proportionalibus defirlbentium<br />

Errores, qui vlribus quibufvis zizqualibus ad corpora fimiliter arjplicatis<br />

generantur, or menfirantur Per difiantias corpw!n a F&<br />

CyrarLlfn Gmilium locis illis ad quz corpora eadem temPorlbus iiL<br />

&m pr0portionalil>llS abfquk viribus ifiis pervenir?W fiat W’quag<br />

drata temporulll in quibuS generantur quam Proxlme.<br />

cOro/. 2. Errores autem qui viribus proportiollalibus ad fimiles<br />

g;‘igurarum fidiunl partes fimiliter applicatis generantW Eunt ut<br />

vires & quadrata temporum conjunRim,<br />

~oro/. 3. Idem intelligendum efi de fpatiis quibu?is ~UX cofpo:<br />

ra urgentibus dive& viribus defcribunt, E&X fiult, Ipfi motus i&’<br />

.tio, Ut vires or quadrata temporum conjunhn.<br />

Co&. 4. Ideoque vires funt ut fjpatia, ipfo motus inicio, defcript~<br />

.dire&e & quadrata temporum inverfe-<br />

CL&. 5. Et quadrata temportim fiint ut defiripta fjpatia dire&e<br />

& vires inverfel<br />

SchoTium.<br />

Si quantitates indeterminate diverforum - generum confcrantur<br />

inter fe, SC earum aliqua dicatur effe ut efi alia quzwis dire&e vel<br />

inverk: knfus efi, quod prior augetur vel diminuitur in eadem,<br />

ratione cum pofieriore, vel cum ejus reciproea. Et (i earwn &qua<br />

dicatur effe LX fimt alk duk vei plures dire&e vel inverk: &nfus<br />

efi, q,uod prima augetur vel diqinuitur in ratione quz componitur<br />

ex raiionibus in quibus ali;r: $eJ aliarum reciprocz augentur vel diminuuntur.<br />

U t fi A dicatur eire ut B dire&e & C dir&e & D ini<br />

verk: khfus ef?, quad A augetur vel diminuitur in ea&m ratione<br />

cumBXGX$, hoc&,<br />

BC<br />

quod A & -<br />

‘<br />

D cult ad invicem in ratio-.<br />

ne data,<br />

,LE’MM’A XI.‘ .<br />

&hn‘* erup@fiicns,.angul~ canl”a&h, iif cufwis 0 f@f&sir/t$ c$pg$&&<br />

ruti $nitam ad, punkwz contufhs haben&w, &‘$~~~o ;q rdll<br />

., ‘tionc .duplicdts JiStenJ~ arcw con~ermiui.<br />

,“.CiJ I, && I<br />

US ilk AB, tangens ejUS 459, filbtenfa aly@i con..<br />

ta&t.u~ ad tangentem perpendicularis B “22, @btenCa arcus ~23, Huic<br />

fihtenf’a= J B 82 tangen ti A 2) perpendiculares erlgantur A G, “B G;<br />

comLp


PRI~CIDI,‘~ MATH’EMATICA: ip 1’<br />

concurrentes in G ; dein accedan t pun&a ‘D, 23, 6, ad pun&a d, b, g, L 1 E E Ic<br />

fitque J interfeeflio linearu m 23 G, A G ukimo fa&a ubi pun&a ‘ZI, B PI< r hx U5*<br />

accedunt ufque ad A. Manifehm eit quod dihntia GJ minor<br />

e$ii Dotefi quam afig:nata quavis. Efi autem (ex natura circulorum<br />

per I;unAa AB G, AIbg tranhuntium] AB qz&A A .=<br />

q~de A G x B D, Sr A b qad, zquale “p9 x b d, [:<br />

I-<br />

adeoque rario AB quad. ad Ab qwd. componitur<br />

eit rati.onibus AG ad Ag 8: B 2, ad b d. c O ,-<br />

Sed quoniam GJ affumi poteft minor longitudine<br />

quavis afignata, fieri potefi ut ratio AG<br />

ad Ag minus difkrat a ratione zqualitatis quam<br />

pro dlfFerentia quavia ailignata, adeoque ut ratio<br />

AB qsiad. ad Ab pud. minus differat a rah<br />

f<br />

tione B D ad bd quam pro differentia quavis<br />

afignata. Efi ergo, per Lemma z, ratio ultima<br />

AB gziad. ad A b quad. xqualis rationi ultimz $<br />

B9 ad bd. &.&. I).<br />

Gas&z. Inclineturjam B D ad AD in angulo ’<br />

quovis data, & eadem kmper erit ratio uTtima BS9 ad bd qua<br />

prius, adeoque eadem ac .AB quad. ad A b pad. $i& ~5;. I),<br />

C&s. 3. Et quamvis angulus 59 non detur, kd re&a B 2, ad da-,<br />

turn pun&urn convergente, vel alia quacunyue lege confiituaturi<br />

tamen anguli 57, d communi lege confiituti ad zqualitatem hnpervergent<br />

& propius accedent ad invicem quam pro differentia quavis<br />

affignata , adeoque ultimo gquales erunt, per -Lcm. r, & prop-’<br />

terea line,?: B 59, bd hnt in eadem ratione-ad invicem ac prius,<br />

.$& E=. 9.<br />

Cord I. Unde cum tangentes ~$53, Ad, arcus A’ B, A 6, & eorum<br />

finus B C, be fiant ultimo chordis AAT, .A b xquales 5 erunt<br />

&am illorum quadrata ultimo UC fubtenh BTD, bd.<br />

L’wol. 2, Eorwndeln quadrata fi~nt. etiam ulrimo ut hat awuum<br />

figttcx quz chordas bikcant &L ad datum pun6hm convergunt.<br />

Nam figittx: illa fimt ut iirbtcnfx BD, bd.<br />

Coral. 3. Jdeoque Ggirta efi .in duplicata ratione temporis quo<br />

corpus data velocitate defcribit arcum.<br />

COPOZ. 4, Trianguln reAilinea AD B, Ad6 fi.rnt ulcimo in cripli- .’<br />

cata ratione latcrum A’D, Ad, inque kfqwplicatn laterum DB,.<br />

db; utpote in compofita ratione lacerum AD, 81: 23 ~3, Ad & db.,.<br />

exibltencia. Sic & criangula ABC, A bc funt ultimo in triplicata<br />

ratione laterum B C, b c, Rationem vero Seii~uiplicatam voco rriplicatx<br />

hbduplicatam, qulc nempe ex fimplici & fiubduplicata cornponitur,<br />

quamque alias SciQuialteram dicunt. ~, ~or.oL<br />

,


42-~&J<br />

@zlerum in his omnibus fupponimus allgulunl co!lta&us .nec 4r$<br />

finite majorem efl”e angulis.conta&uum, quos Circull continent cum<br />

tangentibus skis, net ii&m infinite minorem; 110: efi, curvaturam<br />

ad pun&m A, net infinite parvam effc llcc in+te ~Xq$narn, fiu<br />

intervallum A J finitze ~$2 ma,gnitudinis, Cap dm pot& 2) B<br />

ut ADS: quo in cafi Circulus nullus per punaum A inter tangen*<br />

tern AZ) & curvam AB duci potefi, proindeque angdus conta&ua<br />

erit infinite minor Circularibus. Et fimili argumellto G fiat DB<br />

Kfuccefive ut AD-+, AD, AD, AB7, &cl hbebitur i’eriies angulorum<br />

contaQus pergens in infinitum, quorum quilibet p80Aerior<br />

ek infinite minor priore. Et ii fiat 59B fllcceflivG Lit: AID”,<br />

A in+, ATI:, A 2);) AD+, AD;, kc. habebitur alia feries infinita<br />

.angulorum conta&us, quorum primus efi ejufdem gcneris cum Cir-<br />

.cuIaribus, fecundus infinite major, & quiIibet poficrior infinite rual<br />

j or priore. Sed & inter duos quofvis ex his anguIis pot& Eerie8<br />

utrinque in infinitum pergetis angulorum intermediorum inferi,<br />

quorum quilibet pofkerior erie infinite major minorve priore. Wt:<br />

.di inter terminos A2)’ & ATI3 inkratur ferics ATF$, AZPj”,<br />

A?$, ADS, AT& ADf, AZl$f, ADL?D ki?D”$, &c. Et rwr-<br />

@s mrer binos quofvis angwlos hujus Ceriei inf’eri potefi I*cries noI<br />

.lya angulorum intermcdiorum ab inviccm i&iris intervallis difj&<br />

.rentium, Neque novit natura limitem.<br />

@a de curvis lineis deque fuperfkicbus comprelhenfis dcmQnc<br />

Brata, funt 3 facile applicantur ad folidorum fupcrficies curva~ &<br />

contenta. Prazrnifi vero IXIX Lemmata, ut effugerem tz:dium de&*<br />

.cendi perplexas’demon~ratio~les, more vcterum Geoyctrarum, ad<br />

abfurdum. ContraBiores enim redduntur demoufirationes per m&<br />

:bhodum Xndivifibilium, Sed quoniam durior efi I[ndivifibiliunl hy*<br />

pothfis, & propterea methodus illa lninus Geometrica ccn&tus)<br />

wahi demonfirationes ..rer.um .feguentium ad ulcinlas quantitacunl


3% pHIZO.sOP’HP~~ NA ‘WslLI$<br />

tra&gredi, neque prius attingere quam quantka tes dirninauntw ip<br />

zi”,zt;Yd infinitum. &s clarius intelligetur in infinite magnis. $5 qu.anti.ta,t@$<br />

dux quaram data eii differentia a-ugea$ur in infii,nitum, ,dabitllr<br />

hum ultima raclo, nimirum ratio aquahtatis!, net $arneq idcc3.d*<br />

buntur quantitates ult.imz kL1, max~ilxw quarum !.kl J&$ ratig. . lgit?#T<br />

in fequentibus, fiquando facili rerurn conwptul co.l1fuIfens +.$G~W<br />

quantitates. quam minimas , y.el evanekentes, vel ul tin&s j c,+yye *in-<br />

tclligas quantitates magnkudine decerminacas,. fed ,cogi$a ,C@..p,~P<br />

diminuendas fine limite.


- t?bdeIll plan0 CUm triam@o AS’B. fullge ~‘c’j & tri.angLlium $fi”BCy L! ilbi:<br />

oh parallelas &‘B, t7c, aquale erit tkiangnllo. J’Bc, acqueadeo etiam PKI .GU~~<br />

~ti%nguIo S A’ B. Simili argument0 fi vi,s ccnthpeta fixc&ve agat<br />

in C3 B, E, 8-x. fk5ens uf corpus iingulis, temporis particulis {illgulas<br />

dckribat rehs CT& 53 E, E.F, arc. jacebunt IKE omnes itI<br />

eadcm phno j Sr triangulum SC53 triangulo SB,C, & SI> E ip[i<br />

S-CD, & SEF ipfi PD E xquale erit. f%qualibus igitur temporibus<br />

zquales are% in piano immoto defcribun tur : & cosupone&o,<br />

filnt arearum fummx qwwis SAZ) S, SAFS inter [e, utfilnt tempora<br />

defcriptionum. Augeatur jam numcrus 8.5 minuatur latitudca<br />

t.riangulorum in infinitum; k eorum ultima perimeter AD E, (per<br />

@orollarium quartum Lemmatis tertii) erit linea curve : adeoque vis<br />

centripeta, qua corpus a rangente huju3 curv,x perpetuo retralYitUr*,<br />

aget iad&nenteP j area2 vero qux.vis dekripta: SA9 S, S A FL;s<br />

tcmporibus defcriptionum-fernper proportionales, erunt iii’dem temporibus<br />

in hoc cafi proportionales. &E. 2).<br />

Curol. I. Velocitas corporis in centrum immobile attra&i efk iI2<br />

fpatiis non refifientibus reciproce ut perpendiculwm a centro illo in<br />

Orbis tangen’tem re&ilineam demithn, Efi enim velocitas in Iocis<br />

illis. A, B-, C, 9, B, ut funt bails t~qualium triangulorum AB, BC,<br />

$eEitiy E, E Fj & hx bates knt reciproce ut perpendicuia in iph<br />

.<br />

Cord. 2. Si arcuum duorum xqualibus temporibus in fpatiis non<br />

sefifienribus ab eodem corpor,e fucce~i.ve dekriptorum chords A.&<br />

B C compleantur in parallelogralnmunl. A.BCU, ?x Hujus diagonalis<br />

B,U in ea pofitione quam ultimo habet ubi arcus illi in infinitum<br />

diminuuntur, producatur utrinque j tranfibit eadem per cenrrum<br />

virium.<br />

CoroJ, 3, Si arcuum xqualibus temporibus in fipatiis non r.efilten-<br />

*ibus. defcriptorum chorda A B, B C ac B E, E F compleantur in<br />

parallelogramma ABC U, I> E FZ; vires in B & E funt ad invi-<br />

Gem- in ultima ratione diagonalium B U, E Z, ubi arcus ifii in infiniturn<br />

diminuuntLu’.. Nam corporis motus B C & E F compommtur,<br />

(per Legurn Gorol. I,) ex motibus B:c; B U 8-c Ef, EZ: atqui<br />

B. u & EZ, iph Cc & Ff xquales, in Demonifrationc Propofiiionis<br />

hjus generabantur ab impulfibus vis centnpetx In Is gb:<br />

E, ideoque ,fint his impulfibus proportionales.<br />

Co&, 4, Vires quibus corpora quzlibet: in Qatiis non refifientibus<br />

a motibus re&ilin&s retrahuntur ac detorquentur in orbes cur?<br />

vos funi: inter fk ut arcuum aqualibus temporibus defiriptorum figitr;e<br />

i\l~~qu~ convergunt ad cent;: viriwm, & chardas bikca$<br />

ubt


DF. mUT,‘J<br />

ubi arcus illi in infinitum diminuuntur. I?Jam 1~2 fiagirrrr: filnt fk-<br />

~&oRpO~xuM miffes diagonalium de quibuS egimus in ~orokRiq tertio,<br />

Coral. f, Ideoque vires exdem funt ad vim grayrtatis, ut I~=-&.<br />

gittx ad fagittas horizonti perpendicukwes arcuurn Parabolicorum,<br />

quos projeblia eodem tempore dekrlbunt.<br />

C&k. 6. Eadem omnia obtinenc per Legum Cpyol. IJT, ubi plana,<br />

Sn quibus corpora moventur, Ltlla cum centrls vu-1um qua in i&j.&<br />

Sita fint, non quiefcunt, .kd moventur uniformiter in dlreaunl.<br />

Gas. I. Nan1 corpus omne q,uod movetur in finea ~TTV~,. demr-'<br />

qtetur de curb refiilineo per vim aliquam in ipfum agentem (per-<br />

Eeg. c.) Et vis illa qua corpus de curb re&ilineo detorquetur, &<br />

cogitur triangula quam minima SAB, SBC, SCD, &c. circa<br />

pElun&um immobile S temparibus xqualibus xqualia defiribere, a/-<br />

git in loco B cecundum lineam parallelam ipfi CC (per Srop. XL,<br />

Eib. I Elem. & Leg, I I.) hoc efi, kcundum lineam B S; St in loco<br />

C fecundurn 1inez-m ipfi &2I parallelam, hoc elt, fkcundum lineam,<br />

SC, kc. Agit ergo kmper kcundum lineas tendel~tesadpunLbn<br />

jlhitd immobile S. &E. D.<br />

Gas. 2. Et, per Leg,um Corollarium quinturn, perinde $ five:.<br />

quiefcat, Cuperficies in qua corpw dekribit figuram cwmlrnehn~,<br />

B’ve moveatur eadem una cum corpora, figura defcripta, & pun&w<br />

fuo S uniFormieer ilz dire&urn.<br />

Cwol. I, Irr Spark vel Mediis non refiitentibusx fi areaenon fint:<br />

temporibusproportionales, vires non tenduat ad concurtim radiorum<br />

j *Cedinde.declinant in cchfequentia feu verfus phgam in quarry<br />

fir motus, fCmodo arearum dehiptio accelerattir : fin retardatur, d-c-<br />

&ant in arxecedentia. r I<br />

Carats 2. In Mediis eeiam refifientibus, Garcarum defkriptio acheI&.<br />

satur,virium dire&iones declinant a concurfii. radiorum ve+xs plagam<br />

in gym fit motus, ,> ./’<br />

i&+&&g


Schblium.<br />

urgeri potefi corpus a yi centripeta compoiita ex pluribus viribus.<br />

In hoc cafu knfus Propofitionis efi, quod vis illa qure ex om-*<br />

nibus componitur, tendit ad pun&urn 3. Porro ii vis aliqua agat<br />

perpctuo fecundurn lineam rupcrficiei dkfcriptaz perpendicularem 5<br />

hxc faciet ut corpCPs defle&atur a plan0 fui motus: Gd quantitatern<br />

fiperficiei defcriptzz net augebie net minuet, ‘8~ propterca in..<br />

compofitione virium negligenda efi;<br />

~ROPOSITIO III. THEOREMA Hf.<br />

~COY~US omne, pod rdaio nd-centrum co~pparis dlterim utcunque VZO~~‘<br />

dmto de[cr&it dveax circa centrullrt i&vd tempo&s proportiow-<br />

les, urgetm rvi cmnpojta ex zi cent&pet& tendente.ad colrpus il..<br />

ktid ulterzm, &J ex vi omni mcelewtrice ~UCZ corpus i,Lhd altertm-<br />

iwgetur.<br />

Sitcorpus primum L St corpus alterum T: & (per Legum Coral.,<br />

VI.) ii vi nova,qw:qualis & contraria fit illi qua corpus alterurn<br />

5? urgetur;.. urgeatur corpus urrumque fecundrmm~~hmzas parallelas 5<br />

perget corpus primum L defcribere circa corpus alterum Tarcas<br />

eafdem ac prius : vis autem, qu’a corpus alterum T urgebatur, jam*<br />

defiruetur per .vim .I’_lbi zqualem & contrariam ; & ,propterea (per<br />

Leg. I.) corpus-illud alterum T fibimet ipfi jam rcli&um vcl quic$cet<br />

vel niovebitur unif6rmites in dire&urn : Sr corpus primum L;<br />

urgente diffcrentia virium, I ‘d et?, urgentc vi reliqua perget areas<br />

temporibus proportionales circa corpus. alterum Y dci‘cribcre. Ten-<br />

&t igitur (per Thcor. 1 I.) differentia virium ad corpus illud altc-.<br />

rum TuPcentrum, $2 E. ED.<br />

C’urol. T. Hint ii corpus unum.L radio ad altcrum 2 du@o de*.<br />

kribit areas rempo.ribus proportionales ; atque de vi tota (five fimplici,<br />

five ex viribus pluribus, juxta Legum Corollarium fecundum,.<br />

compofira,) qua carp-us prius ;L urgetur> lubducatur (per idem Led<br />

gum Corollarium) vis rota acceleratdx qua corpus. alterum urg+r :<br />

vis omnis reliqua qua corpus prigs urgeFur tendet ad corpwalter~~rn<br />

Tut ccntrum.<br />

‘- Curd. .2. Et, f 1 arez illa: funt temporibus.quamproxime proporkionales,<br />

vis reliqua tendct ad corpus. alterum T quamproxime.,<br />

CaroZ. sQ Et vkc VC~& fi vis r&qua tendis quamproxirne ad<br />

corpus<br />

tr BES? .’<br />

PRIMUS”


DE h,oru corptls alterurn T, erunt are32 i!lzz temporibus q~~amprO.Xirne pro-<br />

CORPOKUM p~rtiO&lakS.<br />

cO~O/. 4, Si corpus L radio ad alterum corpus r $.&o defkibit<br />

arcas qua:, cum eeniporibus collatz, funt valde. lrlzquales; 8~:<br />

corpus illud alterurn T vel quiefcit vel movetur umforlniter in d,ire~ulll:<br />

a&is vis centripetx ad corpus illud altcrum 7” tenden&<br />

vcl ilulla ek, vel mifcetur & componitur cum a&:ionlbuS, admodum<br />

potcntibus aliariim virium’: Vifque tota ex Qnlni~bW G plures fint<br />

vires, cotnpofif~~ ad aliud (five immobile five mobk) centrumdirigitur.<br />

Idem obtinec, ubi corpus alterum motu quocunque naovcf<br />

ur 3 ii mode vis centripeta fimatur, quz refiat pofi fubdu&ioncm<br />

vis rotius in corpus illud alterum T agentis.<br />

Slcholim<br />

‘i..,.<br />

Qloniam aquabilis arearum defiri,ptio Index- ek Contri,: quad<br />

vis iila refpicie. qua corpus maxime afkitur, quaque refxahitw ~IT.IOtu<br />

recCiheo & in orbita fua retinetur : quidni ufurpemus i;n f+~uentibus<br />

aquabilem arearum deficriptionem, LX Indicem Centri circum<br />

yuod motus omnis circularis in fpatiis liberis peragi-tur .S<br />

PROPOSITIO IY. THEO:REMA W:<br />

Corporuw, qud i&verJos circdos lequabili mot24 deJb&mZ, vires cbm<br />

tr$vtas tid cer,ztrd eortirtdem circdorum~ tendfre j & t$i hger$eh,p<br />

ut Jib< arctium JimMl d&riptown quadrata q@kxg~ dd &c&q -<br />

rum vddios.<br />

Tendunt ha vires ad cktra circulorum per Prop,1 I. & Coral. 13.<br />

Prop. 1; & filnt inter fe ut arcuumzqua1ihu.s temporibus quam midi--<br />

mis defcriptorum finus verfi per Corol. IV. Prdp. 15 hoc eit; ut qu&<br />

,.drata arcuum eorundem ad diametros circulorum applicara @er<br />

.&em. VII : & propterea, cum hi arcus fint- ut atw~s temp,.cni~b;~s~<br />

quibufvis azqualibus defcripti, & diametri iin6 ut eofum radii j Gi-,<<br />

res erunt ut arcuum quorumvis fimul.’ defiriptorum -qua&a ta aqd<br />

plicata ad radios circuIorum. $&EL ‘23.<br />

Coral. 1. Igitur, cum arcus illi fine ut velocitates corporum? vi-<br />

-res centripetzz i‘unt ut velocitatum quadrata applicata ad’ radios<br />

circulorum : hoc efi, ut cum Geometris loquar, v&s funt’ ~JX raw<br />

tione compofita ex dupliqta ration&G&xitatum dire&e .& rziti@+<br />

g fimplici radiorum inverk<br />

cm?&!<br />

,b


PRINCj,]PrA M:A"T'~E'M&T-~~&' 39<br />

'-<br />

C~roZ,‘2.. Et, cum tempera .periodica fint in r@ioae co,mpofita ex ; quem corpus itY*circulo data vi centripeta umformitkrrevo)ven-<br />

..do tOmpore quovis defcribit j medius c@ propwtionalis inter diametrum<br />

circuli,& defcenhm corporis egdena data vi eodemque tem-<br />

.pore cadcaldo ,confcLCkug.<br />

SdiOliUW..<br />

.@afi~s Corollarii Gx ti obtiget in corporibw c.r;elcfl-ibus, (ut .&eo.rd<br />

‘hn colkgerunt ctiam nohates Wrennus, ~~o~~,~~~s Sr I&ZZ~rzs) &<br />

propterea qu,x: ij?e&ant ad vim centrlpcram decrefcentem in dupli-<br />

,ci$a ratiane diRa;tatiarwm a centris, decrevi fufius in kquentibus<br />

Br: xp OIlereo<br />

POX-K.8


4-Q<br />

’ Porro prEcedentis prop& tionis & ~or01la~iOrUn~ e.b!S beIlckio,<br />

DE MoTu<br />

CSORPCIRUM cofligitur etiam proportio vis centripetz ad vim qutmllbet notam,<br />

quaiis efi..ca Grsvitatis. Nam ii corpus in circub .cerrz CO~ICCIZ~<br />

trico Vi gravitatis fu32 revolvatw ham gravitas efi ipfirls vis celttripeta,<br />

Datur autem, ex dekenfu gravium? & temptis reJ’d1utionis<br />

unillS, & arctls data quovis tempore dekrlptus, per hL]Jus COLON,<br />

J[x, Ethuju[modi propofitionibus i%@%itis, in e%imb fro T&%&a.,<br />

tu de .Ebdogio O~ci~htorio , vim gravitatis cuM WIolVelltium vj,<br />

ribus ten trifugis contujiq.<br />

I>emonitrari etiam poiTunt prEcedentia. in IYI.II~C n~odnm, In cir..<br />

..gu~o quovis dekritsi intelligatur Polygonurn lareru!n quotctinque,<br />

Et ii corpus, in polygoni lateribus data cum v$ocltate movendo,<br />

,ad ejus angulos fi@ulos a circulo refle&atur 5 VlS q)Ia fingulis red<br />

flexionibus impingit in circuIum erit ut cjus veIocltas: adeoquc<br />

filmma virium in dato tempore crit ut velocitns illa & numerus re*<br />

A exionum conjun&im : hoc eR(fi polygonum dctw fjecic) ut longi..<br />

tudo dato illo tempore defcripta & longitudo cadem applicata ad<br />

Radium circuli; id et!, UT quadraturn longitudiais illius appl]icatum<br />

ad Radium : adeoque,; Ii polygonurn lateribus infinite diminutis ~0.<br />

.incidat cum circulo, LIP quadratum arcus. dato tempore dcfcripti ap.,<br />

plicatum ad radium. HXC eit vis centrlfuga, ELI" corpus urget &L<br />

culum: & huic zqualis efi vis contraria, qua circulus continLlo rel<br />

-gellit corpus centrum verfus,<br />

-PROPOSITIQ, V. P’I&3LEMA 1.<br />

Figuram defcriptam tangant rcQsr: tres P 29 T@< .Vlt;2 in<br />

-pun& toridem T, & R, concurrentes in T & ,I;): A.d tangellres<br />

erjgantur perpendlcula ..T A, L&..,. R C, ~velo&atibus corparis in<br />

pun&is,illis T, &I? a quibus eriguntur reciprocc proportionaliat<br />

id efi, rta ut fit T A ad RB ut velocitas in $$ad velocitatcm in<br />

13, & $B ad AC ut velocitas. in R ad velocltatcm in J& Per<br />

:perpendiculoruti<br />

: ‘D ~3 EL EC concurrentes in 2, 8r E:<br />

:xem imentro qua&o S,<br />

terminos A,B, C ad angulos reQos ducP;L1tur AZ,<br />

El: ~&LIZ 2’59, *Ffl ,co.t~~~~


Nam perpendicula a centro S<br />

in tangentes z)T, ,$Q?demiffa (per<br />

Gorol. I. Prop.1.) tint reciproce,<br />

ut velocitates corporis in pun&is<br />

T & Yj adeoque per confiru&ionem<br />

ut perpendicula AT, B $&diae&e,id<br />

efi ut perpendicula apun-<br />

&o I> in tangentesdemiffa. Unde<br />

facile colligitur quod pun&a<br />

S,D,;X, hunt in una re&a. Et Gmili<br />

,Argumento pun&a<br />

- -<br />

S, E, Yfint etiam<br />

m una re&ta ; ti propterea centrum Sin concurh re&arum Tz),Y2?<br />

verfatur. $2&E. D.<br />

PROPOSITIO VI. THEOREMA V.<br />

52 corpus inSpatio non reJiJtente &cd centKwn immobile h Orbe quocun -<br />

que re~ohatur,&arcum quemvisjamjdm nufientem tenzpore qudm<br />

~~inimo defcribut,&J&jtta a’ycus dtici intelligatur qud chordam bi-<br />

ficet,&p r0 d u 8 U t rdn f ea tp er centrum Ghrn: erit zlis ceutripeta<br />

in medio arcm, ut jhgittd direlie & tempus his inver[e.<br />

Nam fagitta dato tempore efi ut vis (per Corol.4 Prop.1,) & augendo<br />

tempus in ratione quavis, ob au&urn arcum in eadem ratione fk<br />

. gittaaugetur in ratione illa duplicata (per Corol. z & 3, Lem. XI,) adeoque<br />

efi ut visfemel Sr tempus bis.Subducatur duplicata ratio temporis<br />

utrinque, & fret vis IX fagitta dire&e & tempus bis invert& ,$&a. I).<br />

Jdem facile demonfiratur etiam per Corol.4 Lem. x.<br />

Coral. I .Si corpusP(revolvendo<br />

circa centrum S dekribat lineam<br />

curvam AT& tangat verb re&a<br />

,ZT R curvam illam in pun80<br />

quovis P, &ad tangentem ab alio<br />

quovis Curve: puncto agatur<br />

&I? difiantiz ST paral 5 ela, ac<br />

demittatur 2T perpendicularis<br />

ad difiantiam illam SP : vis ten- V/’<br />

.rripeta erit reciproce ut folidum<br />

I ST pd. x ~Tgzrad.<br />

ii modo folidi illius ea kmper fumatur quaa*<br />

&as, qua: 5i u timi, fit ubi coeunt pun&a T & &<br />

G<br />

Nam ,&R aqualis<br />

efi


2~ denique per pun&urn g agatur L A quz ipfi ST parallela 1, I lx 2 A<br />

fit & occurrat turn circulo in L turn tangenti P 2 in 17. Et Pi’r MU ‘I<br />

~b fimilia triangula %%I?, Zz”T, VT A; erit R T qzcad. hoc<br />

& &. 2; ad XT quad. ut A’V qziad. ad T V qtiad. Ideoque<br />

23 L ’ TmYqZlad* azquatur &Tqtidd<br />

A Y quad.<br />

S F pad.<br />

. DWantur hxx xqualia in<br />

a<br />

22, pun&is I, & xcoeuntibus, kribatur T Y pro .R L.<br />

&R<br />

ic fiet ST qsdd. x FVcub. zrcruale S P quad. x grqwd. Ergo (pea<br />

A V quad.<br />

--zir-- -<br />

STqxTVc&<br />

gloro1.I 82 9 Prop.-vI.)vis centripeta efi reciproce ut - - - -<br />

AV yiwd<br />

id eit, (ob da,tum AYqzzad.) reciproce ut quadratum difiantiz ku<br />

altitudinis ST & cubus chord% T Y conjun&iu~. $22. I.<br />

Jdem aliter.<br />

Ad tangenteni TR ,produ&am demittatur perpendiculum SE<br />

(St ob fimilia triangula STP, VT A; erit AV ad :P V ut ST ad<br />

STXPV<br />

ST quad. x T Vmb. xquale<br />

PIT r, ideoque A y aqualc ST, & --- -<br />

A Vmzd.<br />

$rqgad. x T V. Et propterea (per Corol.3 & 5 PrLp.vr.) vis centripeta<br />

eft reciproce ut ST.qxTVctib. hoc efi, ob data.m AV, reci-<br />

AVU<br />

proce ut SPq XT Vcub. a4E. I.<br />

Coral. I. Hint ii pun&urn datum S ad quad vis centripeta fimper<br />

tcndit, locetur in circumferentia hujus ciqculi, puta ad V; erit<br />

vis centripeta reciproce ut quadratoxubus altituditlis ST,<br />

Coral. 2. Vis qua corpus T in cira.110<br />

AT r Y circum virium ten trum<br />

S revolvitur, efi ad vim qua car us<br />

idem “P in ,eodem circulo & eo’ cf em<br />

tempare periodico circum aliud quod-<br />

%is virium centrum R revolvi pore@,<br />

UC RT quad. xST ad cu bum r@33e SG<br />

~LKC a primo virium centro S ad orhis<br />

tangentem T G ducitur, & ditanti;x:<br />

corporis a kcundo virium centro<br />

parallela ek IYarn> per confiruQionem hujus Pyopofitionis, vis<br />

prior efi ad vim pofieriorem, ut R T q x T Tcz&, ad S T 4 >(: T Ycuba<br />

. . Gz id.


Il.4 MoTU id e&,<br />

CORF'ORUM<br />

triangula<br />

& PWILOSOPI-II~ NA RAEIS<br />

ST cub. XT Ycub.<br />

ut SPxRPqad<br />

T i” cub. five ( ob fimilia<br />

T SC, TT V). ad SGc&*<br />

coral. 3. Vis, qua corpus T in Orbe quocunque circum virium<br />

centrum S revolvitur , efi ad vim qua corpus idem T in eo&m<br />

orbe eodemque tempore periodic0 circum aliud quodvis virium<br />

centrum R revolvi potefi, u~ST x R T q contenturn bque hb dieantia<br />

corporis a primo virium centro 3’ & quadrato difiantiz ejug<br />

a fecund0 virium cenero R ad cubum reQ= SG HUE a primo vi+<br />

rium centro S ad orbis tangentem TG ducitur, Sr: corporis a fecundo<br />

virium centro diftantia XT parallela eR. Nam vires in<br />

hoc Orbe, ad ejus pun&um quodvis T, eadem fimt ac in Circulo<br />

cjufdem curvaturaz.<br />

Hmeatur<br />

r’~oPOS1T10. VIII. PROBLEMA. III.<br />

COYPUS in ~ircuio P QA : ad’hunc effe ffum requiritur Lex<br />

V~.C centripets tendentis dd pun@uvn udeo longinquum S, tit’lineca<br />

wnne-s p S, R s dd idduh, plropawllelis hber~poflv~t.<br />

A Circuli ccntro C a.gatur femidiameter CA parallelas #as<br />

erpendiculariter ficans in M 8~<br />

hoc efi(negle&a ratione determinata<br />

CT qtiad.<br />

,I reciproce ut fp M cub. & E. .L<br />

Jdem facile colllgitur etiam ex Propofitiolle prxcedente,<br />

sc’kroy


~n,Ir;rcx~rA<br />

MATk-HiMATICA;.


46<br />

-p~I[E,ssOPWl& NA IJRALIE;<br />

DIB MaTw pnOpOslTl0 X. PROBLEMA. V.<br />

C=ORPOXUU<br />

Gyypfly”~’ corptrs in EE@: rcpiritur bx cuis centripetce Eendegtis ~LJ<br />

~efmm EUipJe0.r.<br />

sunto c A, ~13 femiaxes Elli fees; G F’, D K diametri conjugar3:<br />

j fp F, * perpenchh a B diametros j ~Z.I ordinatim appticata<br />

ad diametrum<br />

4; cpj & fic0myIeatur<br />

parallelogrammu~~<br />

*PR,eric (exConi-<br />

~i+%~G~d&yad.<br />

LX PC quad. ad CD<br />

p&d. & (ob fisnilia<br />

triangula et, 5PC.Q<br />

@ pad. efi ad 5&f<br />

p&ad. ut T C pad. ad<br />

CT F quad. & con jun-<br />

&is rationibua T’Q G<br />

ad $Q quad. ut TC<br />

pad. ad CD qz&<br />

& TCpad. ad TF<br />

gzt/zd. id ei), v G ad<br />

w<br />

utT Cpd.<br />

,a d cD$ $ ~Fq • Scrdxg. pro? a,& (per Lemma xn,) BC~C~<br />

pro CT) x T -6 net none puo&is T 8~. &coeuntibus, 2 PC pro<br />

T.I G 8~ ch%s extremis & mediis in k ,mutuo, fret ~quad.xTc~<br />

zquale<br />

2 BCqxCAq<br />

clue<br />

e Efi ergo (per Corol~ 5 Prop. ~1.3 vi6


PR”INCIP’IA MATHEh1A:TrC’A. 4i’4’?<br />

dz arcus “Pg erit zquale re&angulo Y? z, ; adeoque Circulus qui L I BE I<br />

tangit SeQionem Conicam in 5? 2% tranfit per :punQum &tranfibit p R1h*U1*,<br />

etiam per pun&urn K qoeant pun&a T & & & hit circulus<br />

ejurdem erit*cukv;iti.zwcufn k&itini: co&a .~TI 2’, & “P Tzqualis erit<br />

‘s. Proinde vis q ua corpus T .in Ellipfi rev,olvitur, erit reci-<br />

PC<br />

2DCq.<br />

proce tit “p C HI T Fq, ( peg Coral. 3 Prop, V.I.) hoc ef? (,ob<br />

datum z I> Cq in T”F$) dire&e ut 5?C. SE. I.<br />

Cur~l. I, Efi igitur vis ut diitantia corporis a centro Ellipkos : &<br />

vicifim, ii vis fit ut difiantia, movebitur corpus in Ellipfi ten trum<br />

kabehte in centro virium, aut forte in Circulo, in quem utique<br />

IEllipfis migrare potek<br />

Coral. z. Et aqualia erunt revolutionurn in ElIipG,bus:univeriis G-<br />

cum centrum idem fa&arum periodica tempora. Nam tempora<br />

illa in Ellipfibus Gmilibus zequalia funt per Corol..3 SC 8, Prop,~v:<br />

in Ellipfibus autem communem habentibus axem .majorem, .fimt ad<br />

inyicem ut Ellipfeon are= cow dire&e & arearum partick fimul<br />

defcriptaz inverfk ; id eR, ut axes minores diretie& .corporum velocitates<br />

in verticibus principalibus inverfe ; hoc e&, ,ut axes illi minores<br />

dire&e & ordinatim applicatx ad axes alteros inveri’e j.kpropterea<br />

(ob zqualiratem rationum diretiarum SE Inver&wm)- in IXtione<br />

zqualitatis.<br />

SCLdi~4?n,<br />

S,i Ellipfis, centro in infinitum abeunte vertawr’ i-n Pkabolam;<br />

corpus movebitur in hat Parabola 5 & vis ad centrum &finite dii<br />

itans jam tendens evadct zquabilis. Hoc efi ,Theorema Ga.Zik&. .<br />

Et fi coni kQio Parabolica, inclinatione plani ad conum fe&um<br />

rnutata, vertatur in Hyperbolam, mQvebicur ccsrp~s in thujus pe-<br />

Minett’o , vi- cefittriptita .‘in r&trifugam, W%I. /. ,$t i$uetnadmobdum<br />

in Circulo vel, ,Ellipfi , fi vires .;re1!dun t, ad, ~cenrruti Gguts:<br />

in A bfciffa pofitum, hae Tires kigendo vel di~inuel~do,Or,dinatas in<br />

Ptitiotie quacunque data, vel etiam .mutando~.zm.gulum ilicliGtionis-<br />

,O.rditiatarum ad ‘AbfciKam, Ikmper ;augentur ,v‘~l .diminuuntur “in<br />

ratio’rie,diltaatiaru~ a.-cen’tro, ii .modo .tkmpara ;periodica matieant<br />

+zjualia:, ketiam in .figuris tllWzrfis, ii ‘Ordinxta augeantur vel di-<br />

‘fiihtiabtur in ratkne~q~wXnque data, Wl‘.a~ngulUs ordinaticmis Ut-<br />

~ztinqoe ‘mutctilr, tiatitin,te :tempor.e periodic0 j vires : ad : oen trum<br />

quo&unque:in .AbTciffa .poG.tt.irn teaden tes dtigen tur vel diminosw<br />

.$.IJ~ $1 :ratiojxC difiafiti~ar-wlll a, centko.<br />

SECTf‘IO~


?De mtu Corporum if2 Conicis Se~ionibm<br />

excentrich.<br />

PROPOSITIO XI. E’ROBLEMA VI.<br />

~~~&.~utu~r corpm in El&p-$ : requiri~ur Lex vis centrajet(t! teB&.-<br />

tis ud ~mbiiicum E&feos.<br />

Efio Ellipieos umbilicus S. Agatur S T kcans Ellipi”eos<br />

turn diametrum 59 K in E, turn ordinatim applicatam %y~ ifi.<br />

g3 & compleatur parallelogrammum $&* P .@. Patet ET aqualem<br />

effe femiaxi majori<br />

AC, eo quad<br />

a6Ia ab alter0 lElli a<br />

fees umbilico H P i-<br />

nea Hf ipfi EC paraliela,<br />

ob azquales<br />

CS, C k!i ) azquentur<br />

ES, El, adeo ut ET<br />

Cemifumma fit i fkrumTS,<br />

T&i f efi<br />

.(ob parallelas HI,<br />

TR & angulos xquales<br />

ITR, HTZ)<br />

iyfirutn T 5’9 T H’<br />

quslz &jun&irn axem<br />

totum 2 AC adaquant,<br />

Ad ST dcmittatur<br />

perpendicularis @.r, & Ellipfeos here re&o principali<br />

‘(fix w)di@o L’ , erit C x &R ad L x T ti ut %I? ad<br />

Tv) id kfl ut TE feu ACad PC; &L XTV ad GvT’utLad<br />

Gv;&GvTad~q~~d.~tTCqtiad.~I CD tiddj &(XCCCXQ~<br />

! 2 Lem. vn,) L@I quad. ad gx quad, pun&is 4 & T coeugtibys,,<br />

efi ratio aqualitatis ; & ,$x qtiLzd. GA.I Rz) quad etl~ ad T quad,<br />

ut E ‘P qtiad. ;Id T Fqi&j id efi ut C Aquat$. ad T F qtrad. % WCS (per<br />

kern... IX.) ut CD quad. ad CB quad. Et conjun&is his omnibus rationibus,L<br />

x 3 R fit ad uquad. ut AC,X .L x P Cq, x CD q, feu z C&g.<br />

xTCq.xC % q. ad TC%GvXCDq‘X$‘Bq. fiveut zTC,+dG.w+<br />

SiXI,


&J,pun&.isL$& T coeuntibus,zeq@tur 2 13 C & G V. Ergo EC his pro- L I tip. I(<br />

portionalia L x XR k &TqtiUd. zquantur. Ducantur hc aqualia in ““’” “’<br />

STq. x&Zt’“q<br />

S’P&fietL%YTq.zguale-<br />

Ergo (per Coral. r<br />

T’<br />

2s<br />

& f Prop. v T.) vis centripeca reciproce efi ut L x SPq. id eit, rcciproce<br />

in ratione duplicata dihntix SP. ,$&&Y,I.<br />

Idem alder.<br />

um vis ad centrum Ellipkos tendens, qua corpus T in Ellipfi<br />

&, revolvi poteit, fit (per Coral. I Prop.x) ut C T difiantia corgoris<br />

ab Ellipkos cencro Cj ducatur CE parallela Elliphs tangenti<br />

T R: & vis qua corpus idem T, circum aliud quodvis Ellipgeos<br />

ptinCtum S revolvi potefi, fi CE &T S concurrant in E, erit ut<br />

PsEGz’* (per Coral, 3 Prop. VII,) hoc efi, G pun&urn S fit umbili-<br />

cus Ellipfeos, adeoque 5? E detur, ut ST q reciproce. ,&E. I.<br />

Eadem brevitate qua traduximus Problema quintum ad Parabolam,<br />

& Hypcrbolam, liceret idem hit facere: verum ob dignita-<br />

,tern Problematis &z uhm ejus in kquentibus, non pigeblt cabs ce-<br />

Pcros demonfiratione confirmare.<br />

PROPOSI”I:IO XII. PROBLEMA. VII.<br />

owamr corpus in Hyperho?a : requiritur Lex vif cenkpet~<br />

.dm,tis ad umbilicnnzfigw~.<br />

tenk<br />

~unto CA, CE fern&axes Hyperbok; T G, .KD diametri conjugatx<br />

5 ‘T F, gt pcrpendicul;l ad diametros; & RW ordinatim<br />

applicata ad diametrum G T. Agatur ST kcans cum diametrum,<br />

9 K in E, turn ordinatim applicatam XV in x, 8.z compleatur pajralIeIogrammum<br />

RR ‘2’X. Patet E T azqulzlem eO% fimiaxi tranfvcrfo<br />

AC, eo quad, a&a ab alter0 Hyperbolz umbilico N linea<br />

.k! 1 ipfi E C parallela, ob aquales CS, CB, zcquentur ES, E 1;<br />

a&o ut E T femidiferentia fit iphrum ‘T S, T I, id efi ( ob parallelas<br />

II!& T R & angulos xquales IT R, HT 2) ipfarum “33 S3<br />

P H, quarum differencia axem totum z AC adzquat. Ad ST de-<br />

-mittatur perpendicularis 2T’. Et Hyperbolz lacere reQo princi-<br />

pali (feu zBCq AC > di&o.LeritLXRRadLxTuut&RadTIv,<br />

IdcAl, ut!&lZ f&MC ad TC; Et.LxTvadGv T ut2h.i<br />

H<br />

GW;


I<br />

/I ‘K ‘.<br />

f Prop. vI, > vis centripeta reciproce efi ut L x Sfpf:, id cf&<br />

n~&mxe in ratiwe dupkata diftantiae SEP~ “_ & 23. %<br />

lii6e


RINCIPIA ~JATHEMAT:J.CA. jar<br />

Idem nliter.<br />

hveniatur vis qua tendit ab Hyperboh centro C, Prodibit [I,rc<br />

d~fianti32 C T proportionalis. hde vero (per C0r01, 3 Ekp ~11 -:I<br />

T E cm5<br />

vis ad umbilicum S tendens erit ut<br />

ST q P hc d-i, ob dtltnm FL’><br />

reciproce ut ST q. L&E. 1.<br />

Eodem modo demonhatur q”od corpus) hat vi ccrltrjpera ill<br />

centrifugam verCa, movebitur in Hyperbola conjugata,<br />

L E M M A<br />

XIII.<br />

LWS re&m Pavabob ad cuerticem quernvis perhem, eJ qlu”‘!uplum<br />

.&jbmthe verticis illius ab umbilico figzirfi. Pate t ex Conicis.<br />

L E M M A<br />

XIV.<br />

&rpen&&m quad ab umbtlico ParaboL ad tmgentew e& demittEtur,<br />

med;im ej! proportiowle &er d$antk 14ddici u p~aitfo cow<br />

$afi!m & a ~erticeprinc~alifigur~.<br />

dicularis ab umbilico in tangentem. Jungatur AN, SE ob zq,uaEes<br />

&?S & S T, MN & NT3 MA & AO, parallela: erunc re&x<br />

kp Al & 0 T, & inde triangulum SAN re&angulum crit ad A Sr:<br />

firnile triangulis zqqualibus SA?M, SNT: Ergo T S efi ad SN,<br />

at SN ad SA. &E. 97.<br />

Cord. I. TSq. efi ad SNg. ut T S ad S-4.<br />

Gk~ok. 2, Et ob datam SA,;fi2SNq. ut P S.<br />

CoroL


Coral. ^D* Et comuriils tangentis cujufvis “PM cwn re&a $N9<br />

~~~f~~~pI qus ab ukbilico in iphm perpendicularis cii-, incidit in re&am AN,.<br />

quz Parabolam tan, flit in vertice principali.<br />

/<br />

1<br />

I<br />

b<br />

peta tendenh<br />

ad mm%icum bu&sjgmw:<br />

Maneat conifruCtio Lemmatis, fitque T corpus in perimctro Parabola,<br />

St a loco xin quem corpus proxime movetuT age ipfi SC??<br />

parallelam $,?? Sr perpendicularem RT, necnon RG tangenti parallelam<br />

& occurrentem turn diametro 2T” G in ZIP turn dihrhz<br />

ST in x. Jam ob fimi ia triangula T x zlj ST M’ St xqualia unius<br />

Iatera S M, ST, aqua \ ia fint alterius latera P x 6% %R SC Cp cu.<br />

Sed, ex Conicis, quadratum ordinate: &w aquale eit: ~c&anguIo fuub<br />

here ret5to & @mento diametri Pu,id efi( per Lem. X111.) re&angw<br />

PO 4 P SX P W, iku 4 T J’ x 2R j Sr pun&is P & &coeuntibus, ratio<br />

,$QY ad a per (per Corsl~. z Lem.vw.) fit ratio azqualitatis, Ergo&pquad~eo<br />

in cafu,3zquaEe JI F/g c:<br />

.*<br />

eR reEt-angu-<br />

**<br />

lo 4;TSx L@?o<br />

Efi autem (ob<br />

fimilia trian-<br />

1<br />

Coral. I. Lem. XI?.) ut s$ id<br />

ad 4SA+~.R, & lnde (per Prop. IX* Lib, v. Elem.) &Tq. 81:<br />

.+ SA X &R azquant,ur.. Ducantur 1733232quaXia in<br />

STq.<br />

-- -$ & fret:<br />

RR<br />

sfi+. x grq.<br />

--A =quale ST q. x 4 Sk k prspterea (per COI*OI. 5 e f<br />

--%B<br />

P~o~~vL) vis centripeta elheciproce u t SF 4. x 4 S A, id e& ~b &..<br />

tam .+SA, reciproceju duplicata ratiane difiantix J’ up. a~., 1,


~nrNCII’I’A AdATHEMAT’IcA. j3<br />

C’nroL 1, Ex tribus novithis Propofitionibus conkquens efk, quod L, BIin<br />

fi corpus quodvis T, fecundurn lineam quamvis reaam “Y k, qua- PRI M us.<br />

cunque cum velocitate exeat de loco T, & vi centripeta qu”e fit reciprocc<br />

proportionalis quadrato difkantiz locorum a centro, fimul<br />

agitetur j movebitur hoc corpus in aliqua h%onum Conicarum<br />

umbilicum habente in centro virium j & contra. Nam datis umbilice<br />

8: pun&o contn&.~s & pofitione tangentis, defcribi poteit fe&io<br />

Conica quz curvaturam datam ad punQum illud habebit. Datur<br />

autem curvatura ex data vi centripeta : & Orbes duo i‘e mutuo tangentes,<br />

eadem vi centripeta dci’cribi non poffunt.<br />

Cored. 2. Si velocitas, quacum corpus exit de Joco ho T, eta<br />

fit, qua lineofa T R in minima aliqua cemporis particula defcribi<br />

pofit, & vis centripeta potis fit eodem rempore corpus idem mo-<br />

-vere per fjatium $R : movebitur hoc corpus in Conica aliqua fe-<br />

Lkione, cujus laws r&urn principale efi quantitds illa - 2% qux<br />

J2!<br />

ultimo fit ubi lineok T R, ZR in infinitum diminuuntur, Circulum<br />

in his Corollariis refer0 ad Ellipfins & caa’um excipio ubi cmpus<br />

re&a defiendit ad cencrum.<br />

S.i corpora plhwa revokvanttir. circa centrzm commme, & zlis centripeta<br />

f;t reciproce In, duplicstu vatione di/?antice locorw a centm;<br />

dim quad ~rbimn Latera recta principaliaJmt in dtiplicata ratioone<br />

areuruna guns cwpora,radiis ad centrmn ductis,eodem tewpore<br />

deJcribmt.<br />

Nam, per Coral, 2, Prop. x31x 1, Latus rc&um E’rrquak eft qua”-<br />

titati<br />

2n*<br />

- qw ultimo fit ubi coeunt pun&a P & 8 Sed !inea<br />

&y<br />

minima &A’, dato ternpore efi ut vis centripcta gcmmnsJ hoc<br />

efi (per Wypothclin) reciproce ut SP4. Ergo gT q* efi ut<br />

-gx-<br />

2 7q! x is,.P 4, I IOC efi, latus rehm .L in duplicata ratione areas<br />

&piST. $$.JL 9.2.


‘pHIjxwizN?WIx NA’FURALIS<br />

54<br />

b 11OTU (;~rol. Hint Ellipfeos area tota , eique proportionale re&a~~guc<br />

.Z~N~U:,~ Jum i*ub axibus, clt in ratione ,compofita ex iixbduplicara rarionc<br />

laccris rcai k rarione temporis periodici. Namque area tota Ed<br />

ut arca :zTx SP duQa in tempus periodicurn.<br />

PROPOSITIO XV. THEOREMA WI.<br />

Namque axis minor eR medius proportionalis inter axem majorem<br />

k latus r&km, atque adco re&angulum fhb axibus eft in rationc<br />

compofita ex i’ubduplicata rationc lateris re&i 8t fifquiplicata .<br />

ratione axis majoris. Sed hoc re&anguJum, per Corollarium Prop,<br />

XI V, cfi in ratione compofita ex fubduplicata rationc Iateris retii<br />

& rarione periodici temporis. Dematur utrobique fiibduplicata<br />

ratio lateris ret%, ‘& manebit Mquiplicata ratio majoris axis squalis<br />

rationi periodici temporis. SE. I).<br />

Curd Sum igitur tempora periodica in Ellipfibus eadem ac in<br />

Circulis, quorum diametri zquantur majoribus axibus Ellipfeon.<br />

PROPOSlhTI.0 XVI. THEOREMA WIT.<br />

$fdm2pojtis, & ~l’fis ad corpora lineis reEis,qm ibidem tunpnt UC<br />

bitm, dexziJ$que all umbilico communi ad has tangantes perpendimiuribus<br />

: dice quad Velocitates corporuwzlunt ipz rations cornpoj-<br />

ta ex ratiople perpendiculorm inruerJe &Jubduplicatu ratime laterm<br />

refformzprincipali~m dire8e.<br />

Ab umbilico S ad tangentem T R demitte perpendiculum ST<br />

& velocitas corporis P erit reciproce in hbduplicata ratione quan-<br />

titatis q. Nam velocitas ilIa eR ut arcus quam minimus Tg<br />

in data temporis particula defiriptus, hoc efi ( per Lena. VII. ut<br />

rangensPR, id eit ( ob proportionales TPX ad Kr8-z J’T ad SJ r’ ) ut<br />

SYXOT<br />

-,I’T’., five ut ST reciproce & ST x u dire&e > efique<br />

,. --<br />

STXRT


PRINCIPIA~nlAT’~E~~ATIrCca.<br />

Tri<br />

6’ 5” X2-T’ LX area dato ternpore defcripta, id efE, per Prop. XIY.<br />

in hbduplicata ratione lateris re&i, SE. D.<br />

~;:JJ;;~ *<br />

coroz. 14 atera re&a principalia funt in ratione compofita e13<br />

duplicata ratione perpendiculorum & duplicata ratione velocitaturn,<br />

.C~rol. 2. VeIocitates corporum in maximis Ss minimis ah wmbilice<br />

communi diifantiis, funt in ratione compofita ex ratione di--<br />

fiantiarum inverfe 6-z fubduplicata ratione latcrum reeorum principalium<br />

diretie. Nam perpendicula jam funt ipk diitantiz.<br />

Cord. 3. Ideoque velocitas in Conica fe&ione, in maxima ve]<br />

minima ab umbilico diftantia, efi ad velocitatem in Circulo in eadem<br />

?I centro difiantia, in fubduplicata ratione lateris re&i principalis<br />

ad duplam illam difiantiam..<br />

Cod 4. Corporum in Ellipfibus gyrantium velocitates in mediocribus<br />

difiantiis ab umbilico communi knt eredr:m qux c.orporum<br />

gyrantium in Circulis ad eafdem difiantias; hoc efi (per. Coral 6.<br />

Prop. xv,) reciproce in fubdupkata rat.ione difiantiarum. Nam<br />

perpendicula jam funt kmi-axes ,mino,res; & hi fint ut medix<br />

proportlonales inter diftantias .& latera r&a. Componatur hqc<br />

ratio inverfe cum filbduplicata ratione laterum re&orum dire&e, &<br />

f&x ratio I‘ubduplicata diitantiauum inverk.<br />

Corok, 5. In eadem figura, vel etiam in figuris divq4s,<br />

quaru~m<br />

latera


no M olu latera re&a prilwipalia 6nt zqLlali& velocitas cor!$xis efi reciprocd<br />

Conronu~ ut pcrpendiculum demiffum ab umbilico ad tangentcm.<br />

CO&. 6. In Parabola, velocitas eit reciproce in fi7bduplicata ran<br />

tionc difiantix corporis ab umbilico figure j in Ellipfi magis variactlr,<br />

in Hyperbola mirw, quam in hat rationc, Nam (per Cortll,<br />

2. Lem. XIV.) perpendiculum demifilm ab umbilico ad tangentem<br />

Parabolz efi in fiibduplicata ratione diitantia. In Hyperbola pcrpendiculum<br />

minus variatur, in Ellipfi magis.<br />

CWOL 7. .In Parabola, velocitas corporis ad quamvis ab umbilico<br />

dikmtiarn, eik ad velocitatem corporis revolventis in Circulo<br />

ad earlden a centro difiantiam, in fubduplicata rationc nwneri binarii<br />

ad unitatem ; in Ellipfi minor efi, in Hyperbola major quam<br />

in hat ratione, Nam per lmjus Corollarium iecundum, v&&s<br />

in vertice Parabolas efi in hat ratione, Sr per Gorollaria fexta hujus<br />

& Propofitionis quartx, fervatur eadem proportio in omnibus<br />

difiantiis, Hint etiam in Parabola velocitas ubique aqualis efi velocitati<br />

corporis revolventis in Circulo ad dimidiam difiantiam, in<br />

Ellipfi minor e& in Hyperbola major.<br />

Gbrol. 8. Velocitas gyrantis in SeEtione quavis Conica efi ad ve-<br />

Bocitatem gyrantis in Circulo in difiantia dimidii late& re&i principalis<br />

Sehionis , ut difiantia illa ad perpendiculum ab umbilico jn<br />

tangentem Se&ionis demifftlm. Parer per Corollarium quinturn,<br />

Cord. 8. Un’dc cum (perCoro1. 6, Prop. IV.) vclocitas gyrantii<br />

in hoc Circulo fit ad veIocitatem gyrantis in Circulo q”ovis aljo,<br />

reciproce in fibduplicata ratione difiantiarum j fiet e:x *quo vclo-<br />

&as gyrantis in Conica k&ione ad velocitatem gyralltis in Circulo<br />

in eadem difiantia 5 ut media proportionalis inter dj~xntiam illamcommunem<br />

Sr fcmin”em principalis lateris red,i, fe&ionis, ad per-e<br />

yendiculum a b um bilico c, ammuni in tangentem G&ionis de-<br />

*mifliuxt.<br />

PROPosIT xv-u. ~R~BIJGMA. IX. _’<br />

.J%@o quad wis centripetuj’t rec~rocepro~ortionalis quadwto d@?m<br />

&v&e locorum u centro, &J pod vis il&s quan&u &!~Jolti~ ~3<br />

cog&d; requiritur Linea quam corps deJcribit, de loco ddta,cum,<br />

~HLJ wlocitdte,/kctinduw ciatm refha egrcdiens.<br />

Vis ccntripeta tcndens ad pun&urn S ea fit qua corpus p in or-<br />

Kra quavis datapg gyrerur, & cognofkatur hujus velocitas in loco p.<br />

De


mWWX?IA MATHEMA’~IcA. 57 ’<br />

e loco T, ficundum lineam T A, exeat corpus T, CUII~ d;;ta vclo- I. 1 If e lr.<br />

tate, ik mox inde, cogente vi centripeta, defleL$at illud in Coni- l’J~l~IusP<br />

fi&ionem T J& Hanc igitur reQa 23 R tangct in ,<br />

jacebit 23 H ad eandem partem rangentis T R cum linea TS,<br />

adeoque figura erit Ellipfis, & ex datis umbilicis S, H, SC axe<br />

principali ST + T .I??, dabi cur : Sin tanta fit corporis velocitas ut<br />

larus r&urn L zquale fuerit z ST + 2 I( P, longitude T H in&-<br />

nlita erit, & propterea figura erit Parabola axem habens SE? parallelum<br />

linear ‘F’.K, & inde dabitur. Qod G corpus majori adhuc<br />

cum velocitate de loco Go P exeat, capiend.a erit longitude “T I+,.,<br />

ad alteram partern tangentis, adeoque tangente inter umbilicos pergente,<br />

figura erit Hyperbola axem habcns principalem xqualem differentix<br />

linearum S”1, & T H, & inde dabitur. $ E. I;<br />

~Corol. I. Hiflc in omni Con&e&one ex dato verticeprincipali 53,<br />

latere reQo L, & umbilico S, datur umbilicus alter Hcapiendo<br />

I) BP<br />

ad I> S ut efi latus reQhm ad difFercntiam inter latus reCtur.n &-<br />

42)S. Namproportio SP+THad ,THut ,zST+zKT ad&<br />

+


s 5’<br />

P~I[EoSoPHe~ ‘NATURALIS<br />

DE hgnvrv in cdii hujus Corolhrii, fit9 S 4-D H ad 2> xk ut .+D S ad I;, &<br />

&;QflPORVhl divifim z)S ad 'DH UC &TIS-L ad L.<br />

COTU~. 2. Unde f’i dacwr corporis veiocitas in verticc principali f;D,<br />

invenietur Urbita expedite , cap&do fcilicet has re&um ejus, ad<br />

duplam difhh~ CD S, in duplicata ratione velocitatis hjus data2<br />

ad velocitatem corporis in Circulo, ad difiantiam 9 S, gyrantis? (per<br />

Coral. 3, Prop. XV-I.) &in I) Had 57 S UC I+s &bn ad difikren~<br />

tiam ink laws w&urn fk L$D S.<br />

Curd 3, Hint etiam fi corpus moveatur in SeQione quacLr.nqW<br />

Couica, 8: ex Orbe fuo impulfil quocunque exturbetwr; cagnofci<br />

pot& Orbis in quo pofka curfum chum peragec. Nam componex+<br />

do proprium corporis motum cum motu ill0 quem impulftls f0h.M<br />

generaret, habebitur motus quoctnm corpus de data impdftis loco,.<br />

kcundum retiam pofitione &tam, exibk<br />

COW!, 4, Et fi corpus ilhd vi aliqua extrinfecus impreffa canti*<br />

IWO perturbetul e3 innotefcel: curfus quam pro;xime, &ligendo mw<br />

xatiolles quas vis illa in pun&is quibufdam inducir, & e:x $‘krki an,ae<br />

logia rnutrttiones continuas in locis. insertnedik zfiimando,<br />

S; corpus 9’ vi centripe.ta ad<br />

pun&u& quodcunque datum R<br />

tendente moveatur in perimerro<br />

data2 cujukunque Se&tionis co+<br />

nicx: cujus centrum fit C, &’ requiratur<br />

Lex vis centripeta : dncatur<br />

C G radio .R T ,arallela,<br />

& Orbis tangenti 5! G occurrens<br />

in 6; & vis illa ( per<br />

Coral. I &I SchoL Prop, x, &<br />

GG<br />

iTfE@z<br />

cl&


‘I’ROPOSITIO XVIII. PROBLEMA X.<br />

Datis umbilico & a&s prhwilpalibus deJcribere Trdje@or&s EIl~ptib<br />

cas & k!yperholidas, ,qzad tmnfibunt perpm&z datlt,& ste@aspo*:<br />

Jtione datas contingent.<br />

Sit S communis umbilicus figurarum 5 AB longitudo axis prh<br />

cipalis Traje&oriz cujufvis; I> pun&urn per quod Traje&oria debet<br />

tranfire; st TR reBa quam dcbec tangere. Cenrro T inter-,<br />

vallo AB - ST, h orbita fit Elliph, vel A’B + ST, ii ea fit Hyperbola,<br />

dehibatur circulus LfG. Ad tange’ntem TR demittatyr<br />

,perpendiculum ST, & producatur idem ad Y’ ut fit TV aquahs<br />

ST; centroque 7 8~ intervallo AIB2defcri.bat-ur circalws PH. Hat<br />

,method 8


60 PHIL~~~PHIE NATURALIs<br />

mcthodo five dcutur duo pun&a ti?', ,p, five dux taqyntes ?‘i?,<br />

tr, five punthm T 6r tallgens A.<br />

fP”R,defcribendi<br />

funt circuli duo.<br />

Sit H eorum inteGeRi colllmunis,<br />

& umbilicis SJY, axe ill0<br />

i?<br />

.<br />

data defcribatur TrajeCtoria. ‘*The<br />

Dice FaBum. Nam TrajeLb<br />

&oria defcripta (ea quad T kl<br />

+S*;P in Ellipii, & 5?H-$Y<br />

in NyperboIa aquarur axi]<br />

tranfibic per pun&urn T J &<br />

( per Lemma fbpcrius ) ranget<br />

n’e&am TR. Et eodem argumento<br />

vel tranfibic eadcm per<br />

pun&a duo “P,p, vel ranget re. /<br />

&as duas TR, TV. .$$ E, .FO<br />

@RoposITIo XIX. Pn,OBLEMA XI.<br />

B


CJZS. I. Dato umbilico S, defcribenda fit Traje&oria ABC per<br />

pun&a duo B, c. @uoniam TrajeQoria datur fpecie, dabitur r;ltio<br />

axis principalis ad<br />

umbilicorum. In ea ratione cape<br />

KB ad 13 S, & L C ad CS.<br />

tris B, 6, intervaliis B<br />

firibe circulos duos,<br />

KL, quaz tangat<br />

L, demitte perpendiculum SG, idemque feca in R & &z9 ita ut fib;.<br />

5’ A ad A G & SLJ ad n 6, ut elt SZ3 ad BK, & axe Aa, yerticibus<br />

A, u, defcribat;ur TrajeQoria. Dice faOmn. Sit enim I+,? unlbilicus.<br />

alter Figurfe defcripta, & cum fit 5Sad A G ue &'a ad a G, erit diviiim<br />

S a - SA feu SN ad B G - AG reu Aa in eadem rationc,<br />

adeoque in rationc quam habet axis prikpalis Figurae &rcribend~<br />

ad diflantiam umbllicorum cjus; SC propterea Figura dekripta cfi<br />

ejufdem fpeciei cum defcribenda. cCumque fiat K 8 ad BS & LC.<br />

ad CS in eadem ratione, tranfibit haze Fjgura per pum%a J3, C, ut.<br />

ex Conicis manifefium ek<br />

Cas. 2. Dato umbilico S, defcriben& fit TIraje&oria quz reQas<br />

duas TR, tr alicubi contingar. Ab umbilico in tangcnces demicccc<br />

pcrpendicula Sa”, St- & produc eadem<br />

ad V, ‘u, ut fmt Z-V, tu fcquales<br />

TJ’, % s. l&if&a V7.I in 0,<br />

& erige perpendiculum infinitum 1<br />

Q f--, cc&amqUe Y$ in&lite pro-.<br />

dLl~a 1ll fe,ca ill d( & k i ta, uc ii r<br />

YK ad KS & Vk ad k S ut cfi<br />

TrajeQork de fcri bend= axis pr incjpalis<br />

ad umbilicorum dikmtiam.<br />

Super diamecro I< k dcfcribatur<br />

_circuIus fe~ans 0 H in I$, & umbilicis S. k& axe princi ali ipfiam<br />

/. H zquante, dei$batur TrajcQoria. Dice fafium. J?f am bii’eca,<br />

J


,6-z<br />

-~~~~osO'PI-TLE NATUI defcribatur Trajeeoria. Dice fat<br />

Qum. Namque VH eire ad<br />

SH ut YK’ ad SK, atque adeo<br />

ut axis principalis Traje6kor.k<br />

defcribendz ad difianriam urn-<br />

:bilicorum ejus, patet ex demon-<br />

. gratis in Cafil fecundol &prop-<br />

. terea Trajeftoriam d&rlptam<br />

ejufdem etk cpcciei cum de’fcrl-<br />

‘benda; reQam vero TR qua an-<br />

~gulus YRS bikcatur, tangere TrajeLkoriam in pun&o A, pates ex-<br />

C onicis. &E. F.<br />

c’as, 4, Circa umbilicum Sdefiribenda jam fit TrajeQoria APB,<br />

.qux: tangat re&am TR, tranfeatque per pun&urn quodvis P extra<br />

.tangentem datum, quzeque fimilis fit Figure ap b, axe principaji<br />

a b & umbilicis s, h dehriptz. In tangentem TR demitte perpendiculumST,<br />

&produc idem ad Y, ut fit TYzqualis ST, any<br />

gulis autem P’S?‘, 5 VT fat angutos bsg, s,lj aciuaks; cenl<br />

troque q & intervallo quad fit ad LJ b tit ST ad 4 S defcribe circuhm<br />

kantem Figuram ap 6 in p. junge sp & age SH qu3e fit<br />

s h ut eR ST ad sp,qwque angulum 3) 5 H’angulo p s k & angul<br />

VS N angulo p s 4 zquales confiituat. Denique umbilicis 8,<br />

%sZ axe principali AB dihntiam YE7 zquante> defcribatur fe&o<br />

Conica. Dim h&turn. Nam fi agatur ,SV quze fit ad sp ut efi J&<br />

ad


VST, bsq) ut efi li”S ad S’S?’ feu ab-ad’pq, 2Equantur ergo+<br />

huh & u b. Porro ob fimilia triangula VSH. ash, efi P’H ad,-<br />

SN ut zrrtJ ad s t5, id efi, axis Gnicrr: fe&ionis jam defcriptz ad ;<br />

illius urn bilicorum intervalIum, ut axis ab ad umbilicorum intervallum<br />

sb-; & propterea Figura jam defkipta fimilis efi Figura<br />

BPS. Tranfi t awem hzc Figura per punLkn P, eo quod triangulum<br />

P S H firnile fit triangulo ps h ; & quiz VH aquacur ipfius<br />

axi & YS b&caFur perpendiculariter a refla T’R, tan@ eadem<br />

rettam TR. &E. I;:<br />

I., E M hf A XVI.<br />

m<br />

purum dij%erenti~ vel dar2tfw rue1 nulld~unt.<br />

C&J+. I; Sunto pun&a illa data A, B, C & puntium quartum 2?$ .<br />

quod invsnire oportet ; Ob datam differentiam linearum AZ, B,2$<br />

locabirutibyunfum 2 in Hyperbola cujus rmbilici fimt A & & &<br />

p


*Gq ~PHILO~OPHIX NATURALIs<br />

DE hjo7 u ad AIA 11t efi ~gr\T ad A& & ereh P X perpendiculari ad A.&<br />

CORPORUM de[lliFaque ZR perpendiculari ad T A! ; eric,ex natura hujUS Hy- j<br />

.perbolz,ZR ad AZ ut efi MA? ad A-B. %nili dikurfuppumhm<br />

z ]ocabitur in a]ia Hyperbola, cujus umbilici funt AP C & princi-,<br />

pnlis axis dlftlerentia inter AZ & CZ,duciquepotefi Z&J ipfi AC .<br />

perpendicularis, ad quam ii ab Nyperbolz hjus pun&o quovis 2<br />

dcmittatur normalis ZS, l-rluc fuerit ad AZ ut efi difkrentia inter<br />

AZ fit CZ ad AC. Dantur ergo rationes ipi’arum 2.R & 2s<br />

ad AZ, PC idcirca dawr earundcm<br />

ZR & ZJ’ ratio ad invicem ;<br />

idcoque ii re&z X P, 5’2 concurrant<br />

in T, & agatur TZ, figura<br />

‘TR Z S, dabitur fpecie, &z re6ka<br />

Y% in qua p~ud3.m Zalicubi IOcatur,<br />

dabitur pofitionc. Eadem<br />

methodo per Hyperbolam tertiam,<br />

cujus umbilici fiunt B & C<br />

& axis principalis diff’erentia reearurn<br />

SZ, CZ, inveniri pot&<br />

alia re&a in qua pi%?urn Zlocatur. 13<br />

Habitis]autem duobus Locis reQilineis,<br />

habetur pun&umquafitum Zin eorum inter&&one. SE, I:<br />

Gas. 2. Si duz ex tribus lineis, puta AZ & BZ zquantur, pun-<br />

Chum 2 locabitur in perpendiculo bikcante difiantiam AB, & locus<br />

alius re&ilineus invenietur ut fipra. sE.1,<br />

Gas. 3- Si omnes tres azquantur, locabitur pun&urn Zin centro<br />

Circuli per pun&-a k&B, c’ trankuntis, g. E. 2:<br />

Solvitur eriam hoc Lemma problematicum per L&rum TaQionum<br />

Apollonii a yietu reflitutum. \<br />

PROPOsn20 xxr. PR~BLEMA XIII.- ,<br />

'~rrajefforium&cd dUtlhiW tinz&!icum a?eJ&ibere, que tyap$&~,pep<br />

puTJg@ d&Z & dhs poJtione da&s contiVJget.<br />

Dar umbilicus Ir, pun&turn fp, & tangens TR, & inveniendus<br />

fit umbilicus alter H. Ad tangentem demitte +rpendiculum<br />

ST”, El- produc idem ad G ut fit TT zqualis ST, & erit TH x-<br />

qualis aXi principali. Jungc ST, .HT, & erit J’T diEer$rtia inter’<br />

MT 8t axem principalem, HOC modo fi dentur plure$tangenD’<br />

tes


RENCXPIA MATHEMA’rxeAt’ Gf<br />

res TR, vel plura pun&a I), devenictur kmper ad lineas totidem EIf%ER<br />

22% ve’l T .H, a &&is pun&is T vel 1’ II I LIJ h<br />

5? ad umbilicum k? du&as , qua vel<br />

zquantur axibus, vel datis longitudinibus<br />

S I-’ diRerunt ab iifdem, atque<br />

adeo quas vel aquantur fibi invicem,<br />

vel dams habent differentias j &<br />

inde, per Lemma fiiperius, datur umbi-<br />

Jicus ille alter H. Habitis autem umbilicis<br />

una cum axis longitudine (qua:<br />

vel efi 2”H; vel, fi Trajetioria Ellipfis efi, T H + SP j fin Wyperbola,<br />

T H- ST) habetur TrajeBoria. SE. I;<br />

Shlium.<br />

Cafus ubi dantur tria pun&a fit fblvitur ex editiua. Demur<br />

pun&a B, C, 59, JunEtas BC, CD produc ad 3 ,fi ut fit EB ad<br />

EC Lit SB ad SC, & FC ad FZ) ut SC ad SD. Ad EF du&m<br />

& produQam demitte normales SG, B M, inque G S infinite<br />

.produ&a cape G A ad AS & G u ad u S ut efi HB ad 6’5’; & eric<br />

A vertex, & A a axis principalis TrajeEtoria: : quz:, perinde ut GA<br />

major, zqualis, vel minor fuerit quam AS, erit Ellipfis, Parabola<br />

vel Hyperbola; pun-<br />

&o a in prim0 cafu<br />

cadente id eandem<br />

partem iinez G F<br />

Cum pun&k0 Aj in<br />

&undo caru abeunte<br />

in infinitum j in tertio<br />

cadente ad contrariam<br />

partem ‘tines G F.<br />

Nam ii dcmitrantur<br />

ad G F perpendicula<br />

CI>DKj erit K’ad HB ut EC ad EB,hoc.e&,utSC’adSB; & viciarn<br />

IC ad SC ut HB ad SB hve ut GA ad SA. Et fimili argumento<br />

probabitur effe .&?D ad $22 in eadem ratione. Jacent ergo pun&a 23,<br />

C, ‘D in Coniktiione circa umbilicum Sita dcfcripta, UC re&3e omnes<br />

ab umbilico LFad fin ula SeBionis pun&a duke, fine ad perpendicula<br />

a ,pu&is iifdem a cf: ,re&am G F demiira in data illa ratione.<br />

Method0 haud multum difimili hujus probkmatis f’olutionem<br />

wadit Clarifimus Geometra de la Hire, Conicorum iilortim Lib-<br />

VIII, Prop. XXV.<br />

K<br />

SECT10


Cm. x. l?onapuxs grim.0 Iinca ad<br />

~ppo@ta latepa-duEtas~paralldas ei”-<br />

$2 alterutri reliquorum laterum,<br />

puta T && T R Iateri AC, Sr T S<br />

ac T Plater-i AI?. Sintque infuper<br />

Qatera, duo ex oppofitis, puta AC<br />

& B B , fibi invicem paralleka.<br />

Et r&a qu;r= bificat parallela<br />

illa latera erit una ex diametris<br />

Conica: k&ionis, & bikcabit eti-


PIlA ~A~;~~~~A~~~~A~ vq7<br />

Gas. 2. Phamus jam Trapezii 4atera Qppofita AC,& B 53 Xlan .P;: ;t;;6<br />

4% parallela. Age B d paraklam &C & occurrentem turn re&az ’ ’<br />

PST in t. turn Couica ie&ioni in<br />

& ipfi +&parallelam age D M<br />

kcantem Cd in M & AB in A?.<br />

Jam ob fimilia rriangyla B T t,<br />

BBN;eit: Bt feuT ad 7tut<br />

TlNad NB. Sic & 5 P eit ad<br />

AR feu T 5’ ut 9 A4 ad AN.<br />

rgo, ducendo antecedentes in<br />

antecedentes & confequentes in<br />

confequentes, ut re&angulum ‘Px<br />

in R r efi ad re&angulum T 5’ in<br />

Tt:, ita re&angulurG NDM efi<br />

ad reQangulum A NB, & (per Caf: 1) ita Akxngtililm F *n 2% ef?<br />

ad reaangulum T S in T t, ac divifim ita rc&angultim ZP 2~ P 23’<br />

efi ad re&angulum T SXT 2”. &E. I>.<br />

Ctis. ,3. Ponamus denique lineas<br />

.quatuor T J?& T 22, I, S, T T non<br />

#effe otirallelas lateribus AC, A B,<br />

fed id ,ea utcunque inclinat&. Ea:<br />

~sum vice age T 9, T r ,parallelas<br />

Jpfi AK’; & T s, T t parallelas<br />

ipfi AB; St propter datos angu-<br />

~10s tfin’~gtllo~uin P &q, h?? 22 r3<br />

!P S’Y~ T T t, dabuntur r&ones<br />

T,&ad Pq, PR ad !i?r, T S<br />

ad ,T s, & T T ad T t; ;itque adeo ratiloties,cohlpofira: 23%~ F R<br />

ad P 4 x 33 P, & .T S x T T ad T s x Pstt. Sed, .per fiperius DDE-<br />

!monfirata, ratio .T q x T r ad T s x T t-data ,efi : &go *‘&&(a<br />

P&X PR ad 5%’ x;TT. Li$ E. CD.<br />

4 E M I+l -A XvIII.<br />

GJdem poJiti.z, J rect~y$vrn ductarum ad oppo&td duo keua Trapexji<br />

I! Qx P Rj?t ad rectangtilum ductarum dd r&qua duo late-<br />

. ra I) S x‘P T iv duta r&one,; panctum I?, d:quo lhe~ ducww,<br />

tanget ‘Con&m<br />

.<br />

fectioaem circa Trtipewium ‘delcriptam.<br />

4<br />

EC2<br />

Fer


n.c Moau<br />

Per pun&a A, B,C, D & aliquod infinitorum pun&orum T’, pu-<br />

CORxlOR v M ta p, concipe Conicam fi&ionem dei‘cribi : dice pun&urn p hanc<br />

fimper tangere. Si negas,<br />

junge A T Gxantem hanc<br />

Conicam k&ionem alibi<br />

quam in Tip, fi fieri pot&,<br />

yuta in 6. Ergo fi ab his<br />

pun&p & b ducancur in<br />

datis angulis ad lateraTrapezii<br />

reCtfe p 4, pr3 p s, $G<br />

& bk, br, b/; 6d; erit<br />

ut bkxbr ad bfxbd ica<br />

(per Lem. XVII) p q Xp 1”<br />

ad ps x ~8, & ita (per<br />

Hyporh.) T JQcT A ad A, %“.,, km” 2 ;<br />

S?SxTTi Efi & Propter<br />

fimilitudinem Trapeziorum b 12 AJ;’ ZD ,$&AS, u.t bk ad bJib&<br />

fP%ad T S. Qare, applicando terminds prioris proportionis a&<br />

terminos correfpondentes hujus, erit b r kl b d ut T R ad T 2. E,Fgo<br />

Trapezia axluiangula I) r bd, 53 R T T fimilia funt, &..earum<br />

diagonales 2) 6, !D F propterea coincidunt. Incidit itaque, b in<br />

interfeeionem reQarum AT, I> “P adeoque coincidit CLW pun&o<br />

9’. Qwe pun&ml T, ubicunque fumatur, mcidit in afignstam<br />

Conicam fe&ionem. L&E. D.<br />

Curd. Hint fi reQ= tres P 2,, “PA, ‘T S, a pun&o comm.uni,T<br />

ad alias totide,m pofitione datas re&as. Af?, CD,1AC, ‘fingule ad<br />

fin&as, in datis angulis ducantur, ctque reaangulum fu:h duabus<br />

du&is P XX ‘P R ad qundratum tertixz T,S .qtiad. in data ,rat,ione :<br />

pun&urn 57, a quibus w&e ducuntur, locqbitur in fc&one Conica<br />

quaz tangit hneas AB, CD in R & :C; & contra. Nag cocat linea<br />

B 2> cum linea AC manente pofit~one~trium,A@,‘ C’D, AC;, dein<br />

coeat etiam Iinea ‘2’ r cum linea T’ 5;: & rc&angulum T S x T r<br />

evader: ‘T Squad. re&xque AB, CD qux. cu-rvam in pun&is A&B,<br />

C tk D Gxabant, jam Curvam in pun& illis coeuntibus non amp$us<br />

lecare pofTunt ied tantum tangent, - .,,<br />

.I @&&, I .,,,.; *. - :( ‘*,<br />

*Non&r, C&i&- fe&ionis, in hoc ‘~en~nxite l&e fiumitur,” ita tit<br />

&%o tan1 Re&ilinea per. verticem Con,i tr&fiens, quam Circularis.<br />

1 bafi parallel~~~neludat~r. Nam ,fi ‘pun@urn,p “incid,it in re&m;. qua,<br />

quavis ex pLllltktiS quatudr A, BI Cj 22 jungiintur, Conica fi@io.<br />

wr t.e-


5, -‘~~~E.OSOPHI~ NATU’bU.,~r$<br />

1 , ad ‘13 S, adeoquc ratio T gad<br />

,“,“,~?u~~ p ,j’. Auferendo hanc a dataratione<br />

P&X ipR ad TJ’x FPT;<br />

dabitur ratio T R ad T Z &<br />

iaddend datas,l*ationes 8’1 iid c’<br />

‘@ 2, & T,T ad T H dabitur<br />

ratio T I ad P 13 aique adeo<br />

pun&urn T. L& E. ir:<br />

CU&, T. Hint etiam ad Loci<br />

pun@oruffi infinitorum 5? pun-<br />

&m yuodvis B taiigens duci<br />

po~ilt. ~~~~ cllorda pi L~bi<br />

puntia Sp ac2> conveniunt,hoc<br />

cfi, ubi 222’ dukitur per pun&m ‘I), tan’gens efiadit. C&o in c2fu3<br />

.riltima ‘ratio evanefcentium 12’ & ‘fp.ZY in’veniietu’r tit fupra. !Ipji<br />

igitur AD due parallelam C.3”” occurrentem B D in F, &-in”eaultima<br />

rat’ione feeQam ‘in E, &,23 E tangchs erit, propterea guod %IF<br />

Sr: ‘evanefcens I H parallelaz funt, & in E & ZP fiii$iter fe&&.<br />

Cbd. 2. ‘Hint etiam~locuspuntiorum omnium ? definiri ‘potcfi.<br />

Per quodvis punQorum A, B, C, I>, puta A, due L&i tangentem<br />

A E & per aliud quddvis Vpun’&um B d,i.rc tangenti parallelam B F<br />

occurrentem. Loco in F. Invenietu’r<br />

autem pun&Mn Eper Lem. XIX.<br />

Bifeca 23 Fin G, & a&a indefinita<br />

.AG eri$‘ pofitio diahetri ad quam<br />

B G & *FG ordinatim applickrntur:<br />

H&x AG “occurrat Loco in H, &<br />

&it, AI7 diameter five lams tranc<br />

verfum, ‘ad Pupd latus re&um crit<br />

ut I3 G 4. ad A G N; Si AG nullibi ‘.)a<br />

occurrit Loco, linea AH exifiente<br />

infinita, Locus erit Parabola & larum<br />

re&ztm ejus ad dianicrrum A G E’%.<br />

. ~23Gq.<br />

pirtinens erit -AG- Sin ea ahhi occurrit, Locus Hyperbola erit<br />

J<br />

subi. pun&~A ,*& e &a funt ‘ad eaiaem .partes ipfius.G : & Ellipfis,<br />

pbr G intermedjumefi, nifi’farte angulus AG’Blreaus-fit “& ififupbr<br />

-8 G qmd. aqude M?tangulo AGH, q.uo in cafiCirculus habehitur.<br />

Artlu~ir~.Pr~blemat~s.~~te~~rn,de quatuor Iineis’ab Euc&&e inczp-<br />

-r?& ab ~‘@O~~O continuati non c&ulus, feed compefitio Geomet&-‘<br />

.ca, qnakm Vet&es $mrebaht, in hoc’ C&qllario &l~ib&r.<br />

LEM..


lela fit ipfi AC & ochwrat<br />

PC’, “PA’, AB in I;,..K,E:<br />

& wit (per Lemma xv1r.J r$-<br />

&angulum DE x D F ad retiangulum<br />

2, G 6 ‘(3 Hi? yaT


. Gwol. I. Wine ii agatur B C fecans T in yj & i? 2’ r* capiarur<br />

p f in ratione ad T r quarn habet 33 T a %- T .R : erlt .El t tangens<br />

C,onica k&ionis ad ~UlltitlJX B. Nam concipe unhm 2) coire<br />

cum pun&o B ita UC, chorda BI> evanetiente, J r<br />

dat j & CD ac B T coincident cum C B & B t.<br />

-tangens eva-<br />

Cord, 2. Et vice. verb ii c<br />

67 t fit tangens, & ad quadvis<br />

Conica k&ionis puntturn<br />

22 conveniant B 93<br />

CD; wit ‘PA ad TT UC<br />

ut T r .ad “Pt. Et contra,<br />

iifitTRadTTutTrad<br />

T t : ,convenient B 2>, CI> G<br />

ad Conic32 Se&ionis puncum<br />

aliquod D.<br />

Cord 3, Conica k&i0<br />

1x211 f&car Conicam G&ionem<br />

in pun&is pluribus quam quatuor. Nam, fi fieri pot&t, tranfi<br />

cant dux Conicx f&Zones per quinque pun&a A, B, C, 5?, 0 j e& ..<br />

que fecet retia B 53 in pun&is D,d, Sr: ipfam T& feces: re&a CGil<br />

in r. ErgoTR &ad TTut Tr adTTj unde TX & Trfibi<br />

invicem xquantur, contra Hypothefin.<br />

LEMMA<br />

XXI.<br />

$i.reB’rt) ducE mobiles & injrpzit~ B M, CM per datapmcta 13, C, ceg<br />

,po?os ducta, coucurJu fuo M defcribunt tertiam pojtione dd-”<br />

-turn rectam MN; & al&z dug infinitce rect& I3 II, C D ctim<br />

prioribws dud~us ad puncta iI/a duta U, C dutos aragzklos<br />

M B DJ M CD egcientes dtikantur ; ho quad hi dule B I?><br />

CD concurJ~Jtio D deJcribe&’ fectionem Conicam per pzmc~~<br />

B, C tr+m~euntem. Et vice wer/lz, /; refb B D, C D con&m&.~<br />

jko D deJ&ibant S ec t’ #onem Conicm per data ptinc~u, B, C; A<br />

tranfeuntem, &$t am&s J3 I3 M Jumper cequalis an&o &at0<br />

A B C, aBguh$que D C M Jemper &qua&s an&o do A. C X3 :<br />

ppunctum M continget rectampojtione datum,<br />

Nan-l


PRI:NCq[~P A”PMEMATICA, 73<br />

LII?tr<br />

&lam in reQa MN detur pun&urn A?, Sr: ubi pua&m mobile YR~ )l 9z >.<br />

J4 incidit in immotum<br />

tumT. Junge CIV,f?j$<br />

A?” incidat punLtum mobile D ill. imnlo-<br />

I<br />

Qp3 B F3 & a pun&o<br />

T age reQas PT, PR<br />

occurrentes ipGs B 2),<br />

C 59 in T & R, & facientes<br />

axlgulum B T T<br />

aqualem angulo data<br />

B N M, St angulum<br />

C p R rq,ualem angug~lo<br />

datoCNM Cum ..,,,,,., 1.....*1.....1.<br />

Hypothefi)<br />

ergo (ex<br />

aequales fint anguli<br />

MBD, NBP, ut &<br />

anguli MCI>, NC P 5<br />

aufer communes NBD<br />

& NCD, & refiabunt:<br />

zquales NBN & PBT,<br />

A?C M & P C R : adeoquc triangula NB M, P B T fimilia finr, ut<br />

dk triangula NC M, T CR. Q:lare T T efi ad NM ut TB ad<br />

ATB, & T B ad ATMutTCadNC, Suntautempuntia B,C,N,T<br />

immobilia. Ergo 5? T & T R datam habent rationem ad NAG proindeque<br />

datam rationem inter f-6; atque adeo, per Lemma xx,<br />

pun&urn 2, (perpetuus reQarum mobilium B r & CR concurfus)<br />

contingit kQionem Conicamn, per pun&a B, C, T trankuntem.<br />

#&.E D.<br />

‘Et contra, ii pun&urn mobile ‘D contingat fi&ionem (hicam<br />

trankuntem per data pun&a B, C, A, 8z fit angulus iD B hgkmper<br />

zclualis angulo dato AI3 C, & anguhsCD CM femper zqualis angu-<br />

]o dato A 2 B, & ubi pun&um~ incidit fucceffhe in duo quxvis ik-<br />

@ionis pun&h immobiliap, T, pun&um mobile n/l incidat fuccci’&c<br />

in pun.&a duo immobilia n9 A?‘: per eadem ny x agatur Rcba fi N!<br />

or lxw erit LOCUS perpetuus pun&i illius mobhs hf. Namj fi f&r<br />

yoteft, VerCetur pun&urn fin Iinea aliqua Curva. Tanget ergo<br />

’ pun&m3 D KeBionem Cofkam per pun&a q$nque 87 C 4 p,Ts<br />

tranfeuntem, ubi pun&m M perpetuo tangit heam Curvam Sed<br />

& ex jam demonfhtis tanget etiam pun&urn 9 fk%onein Coni*<br />

d;ram per eadetn quinque pun&a B, C, Alp, “P ,tranhntcmj ubiFun-<br />

IL.4<br />

htrs


74 wmL?sOPWIX NAT R~~IS .<br />

DE MOT u &urn $1 perpetuo tangit lineam Re&am. Ergo dux f’e&iones C&<br />

CQRPORUU nic3: tranfibunt per eadem quinque pul~fta, co.ntra Coral. 3. Lemi.<br />

xx, Jgitur pucLtun1 Mverkiiu linea Curva abiirrdu~ eU,-. & 8. zb;.<br />

PROPOSITIO XXII. PROBLEMA. 2CI~a.<br />

hifque paralklas TP $9 ?P I?$- per pun&urn ‘quarturn. F,. IIf*;<br />

Inde a poIis duobus 23, C age per pun&urn quintum 2) infini-,<br />

tas duas 13 2) T, CR D,. novifi’me dh&is T F S, I> R &( priorem<br />

prlorl & pofieriorem pofieriori) occurrentes~ in: r & R. ID+nique<br />

de re&is T T, T R, aQa re&a TV ipfi TB aralleIa,. ab-.<br />

f’cinde quahis T t, T r ipfis fp T, T A proportiona s es 5 & fi per.<br />

earum terminos t,. T & polos BP. C a&z Bif, CP concurrant in I<br />

d, focabitur pun&urn illud d in Traje&oria quazfita. Nam puntturn<br />

illud d (per Lemma xx) veriatur in Conica SeLkione~ per:<br />

pun&a quatuor A, B, C, T tranfeunte j &, lineis j? T, 5?t evanef~entibus,<br />

coit pun,&um d cum pun&o 23. Tranfit ergo fetiio Co--<br />

mea per pun&a qumque A, & C,.Ir, 23. &E.D.


RINXPIA MATHEMA 7%<br />

ldem t&m.<br />

E pun&is datis junge triaquzvis A, B,Cj &, circum duo eorum<br />

23, c Cal polos, rota&o angu10~ magnitucfine dates J B c,<br />

ACB, applicentur cfuga<br />

B 4 CAprimo ad<br />

p~d~.~m I>, deinde<br />

ad punhim P, & no-<br />

Centur pun&a M, Nin<br />

quibus altera crura<br />

BL, CL cah utroque<br />

Te decuffant, Agatur<br />

re&a infinity MN, &<br />

rotentur an@ illi mom<br />

biles circum polos fuos<br />

B3 CJ ea lege ut crurum<br />

BL, CL vel<br />

BM, C iI4 in terfefiio<br />

quaz jam fit VJ incidat<br />

fernper in re&am illam<br />

infinitam MN & crurum<br />

B kf, C4 vel BZ>, CCL) interfeRio3 qw jam fit d, Trajefio-<br />

&am quafitam PAZ) dB delineabit. Nam pun&urn d, per km.<br />

XX49 conSingetfe&ionem Conicam er pun&a B, C tranfeuntem ; &<br />

ubi pun&urn m accedit ad pun&a % s M3 N, pun&urn d (per confiru&ionem)<br />

accedet ad pun&a A, ‘D, pp. Dcfcribetur itaque kca<br />

Go Conica tranfiens pi=r pun&a quinque A, B, GT, 21. aE. F.<br />

CoroG, I. Hint re&a expedite duci potefi quz Trajeaoriam quzfitam,<br />

in pun&o quovis data 23, continget. Accedar punfium a’ ad<br />

pun&urn B, & re&a B d evader tangens quzfita.<br />

CouoZ. 2. Uncle etiam Traje&oriarum Centra, Diametri & Latera<br />

.r.e&a inveniri pofint, ut in Corollario &undo Lemmatis x~x*<br />

schol~uM.<br />

I @onRruQio prior evadet paufo fimplicior jungendo B F’, 8~ in eat<br />

i: fi opus eR, produCta capiendo Bp ad I3 P Ut cfi J’ R ad I’ TI &-<br />

: per p a endo re&am infinitam p d ipfi s P ?? parallelam, inClue ea<br />

), capien Lf o fimper p cl squalem T r ; & agenda r&as B d, Cr FQ@<br />

currences in d. Nam cum Gnt 2’ t ad Pt,Q” J? ad PT’J P B ad PBs<br />

2 d ad p t in &em ratione; erunt p d & T t fimPer “41”,“6’<br />

11<br />

L -2<br />

*<br />

L z<br />

PL1YSu4w<br />

3 e x.


les. Hat methodo pud3a TrajeGEoriaz inveniuntur expeditiflmc~.<br />

~~,f!,“~~~ niG<br />

I<br />

mavis<br />

.<br />

(Ihrvarn3. ut in confirm&one keunda, dcfiribere Me:<br />

‘\Q<br />

I.” I’ j.<br />

.krl”,<br />

A.ge $3 53 ficantem S I> in ?Y, & CT? ffcantem P R in,.?& Is&<br />

mquc, agcndo quamvls f r lpfi I” R parallehm,. de T&, P S<br />

abGnde T p3 Tt ipfis T R, T2 proportionales refpe&:ivk - &<br />

a&a&n Cr, B t concurfis d. ( per km. xx ) incidct.. fimpei in,..:<br />

Trajeooriam defcribendam.<br />

.I \d<br />

‘, 8


evolvatur Tim angulus magnitudinc datus CB ff circa polum<br />

23, tum radius quilibet re&iheus & utrinque pro&&us 53 C circa<br />

polum C. Notentur pun&a &f,N in quibus anguli crus B C<br />

f&at radium illum ubi crus alterum BH concurrir: cum codem radie<br />

in punEtis p & D. Deinde ad a&am infinitam M iV con-<br />

,<br />

currant perpetuo radius ilk C T vel CD & anguli crus B C, &‘:<br />

cruris alterius BH concurfus cum radio delineabit TrajeQoriam<br />

qwfi cam.<br />

Nam ii in confiru&ionibus Problematis hperioris accedat punt-<br />

turn A ad pun&urn B, linear CA &CB coincident5 & linea AB in<br />

ultimo fuo fitu fiet tangens B H, atque adee conCtrw&iones ibi po-<br />

Ritz evadent eadem cum confiru&ionibus hit defcriptis. Delinea-,<br />

bit igicur cruris B H concurfus cum radio fetiionem Conicam pes%<br />

pun&ta C, I),T tranfewcem, & re&am BN tangentem m p~ancZo a<br />

B. a$& E, F.<br />

Ch. 2. Dentur pun&a quatuor B3 C, 53, T extra rangenam<br />

,Efk.fica, Junge bina kineis B‘D, C.F. concurrentibus in G, range=<br />

tqLlC


,73 TH~~L~oSO‘PHIE NATURAL,IS<br />

nz MOT u tiqLIe OCCurreiltibus in H 6-z L Secetur tangens in ,& ita ut fit<br />

~f=oam~u~ fiA ,ad AI, ut efi re&angulum<br />

fuuls media propor tionali<br />

inter CG & G P & media<br />

proportionali inter Bh?&<br />

HZI, ad re&angulum fub media<br />

proportionali inter 2) G a<br />

GB & media proportionali inter<br />

P .Z & I c’ j S= erit A pl.lIlCrum<br />

contahs. Nam ii rec3z<br />

P 1 parallela HX TrajeQoriam<br />

fecet in pun&is quibuf-<br />

.vis X & F: erie (ex Conicis)<br />

punEtum A ita locandum, ut fuerit HA qgcad. ad *AI qzddd. in raL<br />

tione compofita ex ratione re&anguli XHZ”ad reaangulum B HOD<br />

feu refianguli C G P ad rekmgulum 2) G B & ex ratione r&anguli<br />

B H ‘9 ad reQangulum T I C. lnvento autern contafius<br />

pun&o A, dei’cribetur ‘Trajeeoria ut in cafii primo. g, E. ~7.<br />

Capi autem potefi] punQum A vel inter pun&a H & .7, vel extra i<br />

.& perinde Traje&koria dupliciter defcribi.<br />

PROPOST.TIO XXIV. PROBLEMA XVI.<br />

dtins pofitione dat4.r cantivget.<br />

Dentur tan entes HI, K-L &<br />

pun&a B, C, f5 . Per puntiorum<br />

,duo quzvis B, 23 age re&am infinitam<br />

BfD tangentibus occurrentem<br />

in pun&is H, I


;BS L 2). Seca autem pro lubitu vcl inter puntga K a 11 _<br />

1 or: L, ~4 extra eadem : dein age R $ fecatlteal rnqyntcs iJa i p’<br />

& T, & erunt A & ‘P pun&a contaftuum. Nam fi .4 G “13<br />

fiupponantur effe pun&a contaEtuum alicubi in tange~~t~~~~ iitaj<br />

& per punhnun H, I, K, L quodvis I, in tatlgcnrc a\-<br />

eerutra .H I fiturn, agatur re&a I T taI2genti alteri K L, par&<br />

lela, qua2 occurrat curve in X & r, & in ea hmatur IZ media<br />

prOpOrtionah inter Ix & IT: wit, ex COniCis, re~aF~~~l~m<br />

XITkceu I2 quad. ad LT qw& ut reQangulum CI’D ad rctta<br />

gulwm 61 L TJ P id eit (per confh&ionem > ur ,.,$‘.I BU&~,<br />

8~ qaad: atquc adeo I2 ad LT ut S I ad S L. Jacent ergo puntta<br />

$, T, Z in una x&a. Porro tangentibus concurrcntibus in G, c-<br />

r,it (ex Conicis) rerftangulum XI T feu I2 quad. ad 114 qwd. ut<br />

GTqaad ad GA qzpad: adeoque 12 & I A ut G-P ad GA. Jacene:<br />

ergo pun&a T, Z & A in una refia, adeoque pun&a S, ‘SD & A<br />

filnt in una reEta. Et eodem argumellto probabitur quad punRa<br />

A, ‘P & A fimt in una refita. Jacent igitur pun&a contahwm A?<br />

& T in re&a R S, HiIce autem inventis, TrajeZIoria d~~~~b~~~~<br />

ut in cafu primo Problematis fuperioris. $& E, F.<br />

L E A4 M P,<br />

XXIT.<br />

reh dua parallel= AO, B L. tertiam quamvis poficione &ran1<br />

AB f&antes in A& 23,<br />

3,<br />

& a figur32 pun&to quo- 9,.<br />

/a<br />

vis G, ad re&am A B ‘e*-t<br />

_ dwatur quavis G I), i<br />

ipfi 0 A parallela. Dciade<br />

a pun&o aliquo 0,<br />

in linea 0 A dato,. ad’<br />

pun&turn 2) ducatur.<br />

r&a 0 2), ipG B L occurrens<br />

in d, & a pun&o<br />

Lt<br />

occurfus erigatur re&a<br />

dg datum quemvis angulum cum reQa 23 L continens, argue cam<br />

habens rationem ad 0 d quam habet I) 5 ad-0 ‘D 5 Sr erlrg p)lnc-<br />

turn in fjgura nova bgz’ pun&o G reipondens. Eadem ratwe<br />

pun&a fingula.figur;e prinw dabunt pun&a totidem figura ~~*p~~ Conc1pe


n 0 MoTV Concipe i&w punhm G motu continw percurrere pun&a oml<br />

~~RPVI~WM .nia figure primx, & pun&urn g motu itidem contiuuo percwrrer:<br />

pun&a omnia figurer: nova 6r eandem defcribet. Difiin&ionis gra-<br />

,tia mominemus 22 G ordinatam primam, dg ordinatam novam 5<br />

.A 23 abfciffam primam., d 1?1! abkiffam novam ; 0 polum, 0 D radium<br />

abfcidentem, 0 A radium ordinatum primum, & 0 a &no<br />

parallelogrammum 0 A E CE completer) radium ordinatum novumP<br />

Dice jam quad, fi pun&m G tangit r&tam Lineam pofitione da-<br />

,tam> pun&um 6 tanget etiam Lineam re&am pofitionc datam. Si<br />

~punQum G tangit Conicam k$kionem, pun&urn g tanget etiam<br />

Conicam f&kionem. Conicis k&ttioni bus hit Circulum annumc ro.<br />

Porro ii pun&um G tangtt<br />

Lineam tcrtii ordinis<br />

Analytici , punfium g<br />

tanget Lineam tertii itidem<br />

ordinis; & fit de<br />

curvis lincis fiperiorum<br />

ordinum. Line= dua: e-<br />

runt ejufdem femper ordinis<br />

AnaIytici quaspun-<br />

&a G, g tangunt. Et-<br />

.enim ut elt ~zd ad OA<br />

.ita film 0 d ad 0 I)> dg ad DE,,& A.23 ad:ATI 5. adeoque AD<br />

zqualis efi OAXAB ,& 2) G Equalis efi<br />

nd<br />

tum G tangit rek%am Lincam, atque adeo in zqwtione q,uav&<br />

aqua relatio inter abfiiffam AD & ordinatam ‘53 G habetur, illdeterminata<br />

ilk AD & 53 G ad unicam tantum dimenfionem<br />

afcendunt, .fcribendo in hat azquatione<br />

QdxAB<br />

rlz d pro PD, &<br />

OAx cd-<br />

-pro ‘53 G, producetur xquatio nova, in qua ;abi‘ciff$, nond<br />

va ad & ordinata nova d ad unicam tantum dimenfionem afcendent,<br />

atque adeo cpz de E Ignat Lineam re&am, Sin AD ,& 2) G<br />

‘(vel earum alterutra) afcendebant ad duas dimenfiones in aquati..<br />

one prima, akendent itidem d d & dg ad duas in xquatione fecux~da.<br />

Et iic de tribus vel pluribus dimenfionibns. Indeterminate<br />

a d, 4~ in aquatione fecunda & ATI, 13 G in prima hxndenc femper<br />

ad eundem dimenfionum numerum, & ‘propterea Line,~, quas<br />

pun& G3.g tangum> Cunt ejufdem ordinis Anal,ytici.<br />

Dic0


PRIkl@IPIA MAT’I-IE’MATICA. $n<br />

,Dico przterea quad ii reQa aliqua tangat lineam curvam in figura<br />

prima 5 hlec reQa eadem modo cum curva in figuram novam<br />

tranflata ranget lineam illam curvam in figura nova : & contra. Nam<br />

fi Curvx pun&a quavis duo accedunt ad Envicem & coeunt in frgura<br />

prima, pun&a eadcm tranflata accedent ad invicem & coibunt<br />

in figura no,va, atque adeo re&z, quibus lwx pun&a junguntur, G-<br />

mu1 evadent curvarum tangentes in figura utraque. Conrponi pal:<br />

Ifent harum affertionum Demonitrationes more ma&is Geomecrico.<br />

Sed brevitati conliilo.<br />

Qitur fi figura reQilinea in aliam tranfinutanda efi, fuflicit rectarurn<br />

a quibus conflatur interkkl.iones transferre, & per eafdem<br />

in figura nova lineas re&as ducere. Sin curvilineam tranfinutare<br />

oportet, transferenda fiint pun&a , tangentes 82 alix reEt32 quarum<br />

ape curva linea definitur. Infervit autem hoc Lemma folucioni.<br />

difficiliorum Problematum, tranfmutando figuras propofitas in fimpliciores.<br />

Nam re&a quzevis convergentes tranfmutantur in parallelas,<br />

adhibendo pro radio ordinato prima> lineam quamvis<br />

reQam qux per concurfilm convergentium tranfit : id adeo quia<br />

concurfus ille hoc pa&o abit in infinitum, linex autem parallel32<br />

fint qua: ad pun&urn infinite difians tendunt. Pofiq~am autem<br />

Problema folvitur in figura nova, ii per inverfas operationes tranG<br />

xnutetur hat figura in figuram primam, habebitur Wutio quxfita.,<br />

Utile efi etiam hoc Lemma in folutione Solidorum Problemat,um.<br />

Nam quoties duz- fe&iones Conic= obvenerint, quarum interfe&ione<br />

Problema folvi potefi y traniinutare licet earum alter-<br />

LItram, fi Hyperbola fit vel Parabola, in Ellipfin : deinde Elliph<br />

facile mutatur in Circulum. ReLta item 82 feLti Conica, in confiru&ione<br />

Planorum Problematum, vertuntur in R&am & Circulum.<br />

t II I 14<br />

1 lt’uuSb<br />

PROPOSI~IO XXV. PROBLEMA XVII.<br />

Per concurfum tangentium quarumvis duarum cum fe invicem, &<br />

concurfium tangentis tertiaz cum reQa illa, qun: per pun&a duo data<br />

tranfit, a .e re&am infinitam ; eaque adhibita pro radio ordinacoprimo3tran<br />

f; mutetur figura, per Lemma fupecius, in figuram novam. In.<br />

h/l:<br />

hat


hat figura tangentes illae dug evadent fhi’invicem parallela, & tani<br />

gens ;krtia fier parallela w&3: per<br />

purdta duo data rranfeunti. Sunto<br />

h i, k I tangentes ills duz paral’tela,<br />

ik cangens tertia, & b G re&a huic<br />

parallcla tradiem per pun&a illa<br />

n, b, per qua&onica fe&io in hat<br />

figura nova tranhe debet, & p.arallelogrammum<br />

b i k I complens.<br />

Secentur reke h i, ikj !z I in C, d, e,<br />

ita ut fit h c ad latus quadraturn<br />

rdtanguli nbh, z’c ad idj tic ke<br />

ad kd ‘UE efi iiln~ma r.e&arum hz’<br />

& kI ad fummam rrium _ linea-<br />

s:eCta ik & Intus qwadratum re&anguli &I&. Habentur igirur ez<br />

data illa ratione pun&a conta&ium c, dy 8, in5 llgura nova. l&T<br />

innerfas o-perationes Lemmaeis- ncwiflki cransferantar hat puw<br />

.-&I in figuram primam & ibi, per Probl. XL’V, d.e&ribet.ti<br />

TrajeQoria. $$. E. I;. .C eteru,m perinde LX pw&a ti 9 6 j+<br />

cent vcl inter punEta h, i, vel extra, debent pun&a c, d, e UCI<br />

inter punQa h,. z’, 4, k capi, vel extra. Si pun&orun~ a, b al..<br />

terutrum cadit inter pun&a h, J,, EC akerum extra> Problema, iIn-,<br />

pofibde elk


PRINCIPIA MATHEMATS.CA. 33<br />

%a, & eadem pro radio ordinate primo adhibita, tranlcnutetur fi- L : B E i?.<br />

gura (per Lem. xX11) in figuram novan.3, & tangenres bins, qua2 nd PR! &lIJ s0<br />

radium ordinatum primum concurrebant,jam evadentparallcls. haeo<br />

ilh k i & k Z, i k & h I continentes parallelogrammum hi k 1, Sitgage<br />

p punh.w in hat nova figura, pun&o in figura prima dare<br />

refpondens. Per figwe centrum 0 agatur pq, & exiRence Qg azquali,<br />

Qp, erit q pun&urn alterum per quod f&&o Monica in hat<br />

figura nova tranfire d&et. Per Lemmacis xxx,1 operationem ii9<br />

verhm .transferatur hoc pun&urn in %iguram primam, & ibi habebuntur<br />

pun&a duo per qulr: Trajehria dehibsnda ek Per eadem<br />

vfcro defcribi potefi Traje&oria illa per Prob, XVII. &E. F.<br />

L E M M A<br />

XXIII.<br />

,$z” recta? dad poJitione data AC, BD ad data puncta A, B, tevminenttir,<br />

datamqud lubeant rationem ad invicem , & reb?~~<br />

C D, quct pt&a indeterminata C, D junguntuu; Iecetw in ra-<br />

#ione data in K: dice quad ~US&W.V MI focub&~ in r&a pofib<br />

.6 *<br />

d;ione datu,<br />

Concurrant enim re&az AC,<br />

’ 232, in E, &in BE capiatur BG<br />

ad AE ut eiZ BfD ad AC, fit-’<br />

que 5’2) femper xqualis dats<br />

25 G; & erit ex conitru&ione<br />

BCadG2), hocetI,ad EFut<br />

AC ad B ‘59, adeoque in ratione<br />

data, & propterea dabitur fpecie<br />

triangulhm -2 FC. Secetur CF<br />

in 2; u t 13 t C L ad C F in ratio- p”’ ~.:**“”<br />

a 6 nk u<br />

ne CK ad CB; &, ob datam illam<br />

rationem, dabitur etiam fpecie triangulum E FL j proindeque<br />

gun&um L locabitur in re&a EL pofitione data. Junge L K, &<br />

hilia erunt triangula CL K, C FYI 5 &, ob datam F”D 6c datam<br />

rationem L .K ad P”J), dabitur L K. Huic qualis capiatur EH,<br />

& erit kmper EL .KH’ parallelogrammum. Locacur igitur punt-<br />

&urn Kin parallelogrammi illius here pofitione dato .H.K $$,B. f-ll.


PR:II+KIPIA MATH-EMATI@A, 3y<br />

L E M M A<br />

XXV..<br />

LI?SEW<br />

pRrXrlJS*.<br />

‘Tangant parallelogrammi ML 2-K laterxquatuor ML, IK, KE,<br />

HI fe&ionem Corkam in A, B, C, 9, & Cecet tangens quinta Fq<br />

h2x lacera in F, & H em A. I4<br />

&E; hnantur autem,<br />

laterum MI, KI abfciE3<br />

ME, K.$& vel,<br />

laterum KL, ik?L abfciffz<br />

KH, MF: dico<br />

quod fit M.E ad<br />

Ml ut B Ii ad IC2@.<br />

& KH ad- ILL ut.<br />

AM ad. MF. ~Nam<br />

per CorofIarium G- .H<br />

cundum Lemmatis fiiperioris, efi ME ad E I ut (A Ml&) B K ad<br />

B& & componendo ME ad Ml ut B IC ad I


$G<br />

nF. hloa w dcm r&a per medium omnium Eq, e,& MAY5 (per Eem. xxrlz)<br />

CoRPORU:l & uw%um r&x AlK cfl centrum SeQionis.<br />

:p~


PRINCXPIA M”ATHElE1A~TJC’A4. s,pf<br />

gent,es alias qua&is duas G CD, I;D E in L SC I


l)r ‘l!-tOTU dum Trajeeoria defcrlbebatur, demitte normalem 0 H CircuIo oc.-<br />

(SoaPonukI currentem in JX 8Z L. Et ubi crura illa altera CK, BI< concur4<br />

runt ad pun&urn iilud I< quad LZegul~ propius efi, crura prima<br />

Cfp, B F’ parallela erunc axi majori, & perpelldicularia minori ;<br />

& contrarium eveniet fi crura eadem concurrunt ad punEh~ relno.-<br />

tius L. Unde ii detur Traje&koria: centrum, dabuntur axes. Hi{ce<br />

autem datis, umbilici itint in promptu.<br />

Axium vero quadrata firnt ad inpicem ut J{fJ ad & 22” & in&<br />

facile eft Tra jec%oriam 1-P<br />

fpecie datam -per data<br />

quatuor pun&a defcrihere.<br />

Nam fi duo ex<br />

pun&is datis co&i tuantur<br />

poli C, B, tertium<br />

dabit angulos mobiles<br />

T CI!!, YBKj his autern<br />

datis defcribi potefi<br />

Girculus I B K G C.<br />

Turn ob &tam fjpecie<br />

Trajectoriam , dabitur<br />

ratio OH ad 0 I<br />

8r re,&a qua tangit hunt circulum,& tranfit per concurlum crurutn<br />

(71(, B K, ubi crura prima CT, B T concurrunt ad quartum datum<br />

pun&urn erit Regula illa MN cujus ope Trajetioria &h-ibetur.<br />

Unde etiam vicifim Trapezium fpecie datum (fi cafis qt.&<br />

-dam impofibiIes excipiatlrur) in data quavis Se&tone Conica infiribi<br />

poteff,<br />

Sunt 8z alia Lemmata quorum ope TrajeBoria fpecie datz 3<br />

,datis punfiis & tangentibus, defcribi poffunt. -Ejus generis<br />

efi quad > ii re&a linea per punknn quod’vis pofitione datum<br />

ducatur, qure datam ConikBionem in pun&is duObus interfk-<br />

‘cet, & interk&ionum intervallum bii’ecetur, pun&urn biiek’kionis<br />

tan&et aliam Conife&onem ejufdem fpeciei cum priore, atsue<br />

axes hbentem prioris axibus ~arallelos, Sed proper0 ad magis<br />

u.tiIia,


Dantur pofitione tres re&x infiuitx .,&.B, AC, B C, & oporret<br />

triangulum 21 E P ita locare, ut angulus ejus 523 lineam ~4 B,<br />

angulus E lineam AC,<br />

e<br />

zz amzulus F lineam<br />

SC taggat.Super I) E,<br />

_ 23 F & E F defcribe<br />

2ria circulorum k -<br />

nnenta VR*E,fDG 5 ,<br />

EMF, qux capiant<br />

angulos angulis B AC,<br />

AB C, A CB xquales<br />

refpeQive, Dekribandur<br />

autem hxc kgmenta<br />

ad eas partes Iinearum<br />

ZlE,VF, EF ut<br />

literx 2, R E I) eodem<br />

ordine cum literis<br />

,<br />

. ,A B C A, & literx<br />

E MFE eodem cum<br />

literis ACBA in orbem<br />

redeaut j deinde compleantur<br />

11zc fegmenta<br />

in circulos in tegros,Secent<br />

circuli duo<br />

resfemutuoinG,<br />

que centra ,eorum<br />

$i& JunEtis GT,<br />

ca$eGa ad AB<br />

:GT zid T & & cen-<br />

IXO G, intervallo Gd<br />

,defcribe circulum, qui fecet circulum pritiua GE in a. Jtmgattit<br />

gum n 2) . .-@cans circulum fkcundum 2) F G in 6, tum Al $ ficans cir-<br />

N<br />

CalLla


DE<br />

CmlPORU<br />

MOTU<br />

hl<br />

90 PHI~EOSO~PHI~ NATURALIS<br />

culum tertium E MF in C. Et compleatur Figura ABC de f i%xiJlis<br />

& zqualis Figure ab c I) E E. Dice fa&um.<br />

Agatur enim EC ipfi n!D occurrens in n, & jungantur a,G, b.,C;<br />

g&)-Cli”& 8% angulus<br />

a cF xqualis angulo<br />

ACB, adeoque criangulum<br />

n 72 c triarlgul0<br />

.df B C 32quiangulum.<br />

Erg0 af3g~1h~ a nc feu<br />

FlaTI angulo ABC,<br />

adeoque angulo Fb 2)<br />

aqualis eR: j K- propterea<br />

pmLhm B incidit in<br />

p~~m%m b. Pot-r0 ang~dus<br />

GT 2, qui dimidius<br />

eit anguli ad<br />

centrum G T D,xqualis<br />

eft angulo ad circumferentiam<br />

G B ‘2) 5.<br />

& angulus GRT, qui<br />

dimidius efi anguli ad<br />

cfqltrum G$p, X”<br />

qualis efk complemento<br />

ad. duos reQos anguli<br />

ad circumferentiam<br />

G b I), adeoque x-<br />

qualis angulo G b a 3,<br />

funtque ideo triangulaGTL&<br />

Gab Mimiha;<br />

&z Ga eit ad ah


&vv~. Hint re&a duci potefi cujus partes longitudine dac.rrc& B,EZISE<br />

tribus pofitione datis inrcrjacebunt. Concipe Triangulu~~ CD E r;, pn 1 g u a*<br />

pun&k0 2) ad latus E F accedentc, & lateribus ‘DE, 23 .F in di..<br />

reQuni poficis, qwtari in lineam re&m, cujus pars data DE rcceis<br />

pofi-tione da,tis A& AC, & pars data a3 F x-e&is pofitionc da-<br />

& AB, B C interponi debet; 8~ applicando con4htiioncm prx~<br />

cedentem ad hunc,‘cacqm folvetur Jhblcma.<br />

*. ‘PROPOSITIO XXVIII. PRQB,LEMA xx.<br />

Defcribenda fit Traje&oria qua: fit fimilis & zqualis Linez cut--<br />

vz 2) a F, quxque a r&is tribus AB, AC, B C pofitione datis, in<br />

artes datis hujus partibus Z)E & E F fiiiles & xquales<br />

irur.<br />

feca-


PRIbJCI.P.IA ,MATHE-MATICk: 331<br />

bf~~qdalern a!lgulo, B,dB,, fecundurn F’TH. capiat angulum X-<br />

qualem, gg~~lo ,cKD, ac tebum F VI. capiar’angnlum ;~qualem 1k:a”,“6.<br />

gggu1q-J 8 c E., Dekribi ,autel!l debenr fkgmenta ,ad eas pwtes IInearurn<br />

FG, FN, FP; UC literarum FJ’G F idem fit ordo, circular:is<br />

qui Ii.terarum B AD B, utque liters E2HF eodem ordine cum<br />

literis CBB C’, & liter2 FYIF eodem cum literis &CEA. in:or-.<br />

by@eyf., ~omp!e~ntur fegm;yta in circulos incegros, 4tque ‘P<br />

Sntr.um ,,clPr@i,R&-L~ FJG, &$qetitrum f’ecundi:EI”H. Jungatur<br />

& ~~$~KJLI~ prc$&.wat~~r .f;pl@&& in ea capigtur RRin:ea ratiorje ad<br />

fip&quam habet BC ad A.& Capiatur aurem &R ad ens partes<br />

jpurifii gut literarum T, ,$.& X idem fir ardo atque literarum<br />

A,.B, C: centroque& 8-z intervallo pi F dekribatur ckculus quartus<br />

FNc fekans clrculum .@rcium FYI in C. Jungatur .Fc kcans<br />

circuIum primum in a & kcundum in 6. Aganrur n G, b H, c I, Ss<br />

E’igur3: a b cFG NIfimilis confiituatur Figura AB Cfgh5;: Eritquc<br />

‘IYrapeziumfghi illud ipfilm quod confiicuere oportebat.<br />

Secent’ enim circuli duo primi FSG, FTH fi mutuo in I


Pi ‘PHI[‘LOSOPHI~ NATURii~-lS<br />

Producantur AB ad K, & BD ad L, ut fit B K ad AB. &<br />

H1ad GHj 8r: 5D.L ad BD ut GI ad FGj & jungatur K&<br />

occurrens retiaz C E in i. Producatur i L ad &l, UT fit I, M ad t’ L;<br />

ut G H ad HI, & agatur turn MR ipfi L B paralfela r&sque<br />

AZ) occurrens in g, turn 6 t fecans A B, B 13 in f, h. J&xi<br />

fa&um. :<br />

Secet enim Mg reEktam AB in 2, & AfD p&ka~ KI; in S,--&4<br />

agatur A’P qua? fit ipfi B 2) para*IIela & occurrat iL in” T, ‘&<br />

erunt gM ad Lh (gi ad bz’,.Mi ad&i, GI.4 ‘HI, AK ad<br />

.B K) & A.P ad B L in eadeti ratione. Secetur’ ‘ZJ L in A ut fit<br />

&.<br />

.<br />

., ,,<br />

i .-,,~<br />

2> z ad R L in eadem illa ration6 & ob ‘proportionales g $ a$<br />

g‘&f, -AS ad AT, & IIS ad DL; erit; ex zquo, ut!gJa$ ‘l&b it+<br />

AS ad BL; &fpJ ad RLj & mixtim B.t?.d-.&!L ad &.‘h-Bz<br />

,ue AS--Z>S adgS; AS. Id efi BR ad Bb ut A$3 ad Ag a+<br />

eoque ut BED .ad g&$ Et vicifim 23 I?* ad 4 2) ut 2% ad &J& Gzu<br />

f b ad fg. Sed ex cosfiru&ione linea i3.L eadeti ration, G.&a #f&z<br />

in “;D a R atque hea 2U in G & W: ideoque, efi 6’ ,B’D.<br />

ut FH ad FG, Ergd j% eff ad fi ut FHad FG. i&ur<br />

fit: &am gi ad Bi’ut Mi ad L i, id efi, ut GI ad H.G patet li-<br />

.neas F..& Jj ing & b, G & H fimiliter Ee&asaefi. $& 23. x7.<br />

In


PRINCIPIA MATHEMATICS,<br />

3P<br />

Tn confiruQione Corollarii hujus pofiquam ducitur I, [< fecans L I,tR<br />

C,?Sini,producerelicet ;E ad K ut ikETad Ei UC FH ad HI, PKranwaJ<br />

& agere Yf parallelam ipfi BD. Eodem recidit ii centro i, ill..<br />

tervallo 1 H, dcfcribatur circulus Pecans B I> in .X3 & producatur<br />

iX ad & ut fit 5 r aquaI@ ?F, & agatur Tf ipfi B ZI parallela,<br />

, ,IQpblematis hl;l jus folutrones alias Wrennus & ~JKXZzjks ohm excogltatxnt,<br />

* I S<br />

‘,,..<br />

I”R~?OSI.?‘IO XXIX. PROBLEMA XXr.<br />

Defcribenda<br />

4% Traje&xiafit<br />

Line& curvae<br />

curva Linear L;G HI conGmilisl<br />

,.:-(. ’ ., .’ ./ I<br />

r’. ,<br />

,,‘” i .r<br />

:<br />

I,<br />

,,<br />

n<br />

, /,‘,j’<br />

:, (’<br />

. :; .;<br />

I


96 -E’PFm.J3S~.P~HI~’ YiGv-rURAkIS<br />

D~‘MOTU<br />

Schoiium.<br />

conl~or~uu<br />

Ckmitrui etim poteD %oc Problema ut kquitur. JUllEtiS FG,<br />

GH, HI, FI produc G-F ad V, jungeque FH, IG, & angulis<br />

FGH, VFN F ac angulos CAY, CD Al; .iquaIcs. Concufran t<br />

.A? K, AL cum re&a B’D in I< 8c’ %, & inde agantur KM, L Ng<br />

quarum IiTfif confiituat anguium Ifi7KM zqualem angulb GHI;<br />

fitque ad AK uL: eCt HI ad G.Hj & LN conflituat an&urn<br />

AL .N zqualy angulo FH-I, fitque ad AL ut HIad EEL Ducantur<br />

autem AK, Kik& AL, LJT ad eas partes linearum A%&<br />

AK, AL, UC lilerx CAKMC, ALKA, DALN2) eocIem<br />

ordine cuin literis ‘FG k?‘IF in orbem red&t,; si: , a&a MA? OC-<br />

~.currat r&txf-C E h”i. ad’anguluk’i E !P aqkdern &gtilti ZGkT;<br />

,’


Sit S umbilicus & A vertex principa-<br />

‘lis Paraboh, fitque 4 AS x M zquale<br />

areas Parabolicz abfcindenda: A 5? S,<br />

ua: radio 823, vel poll excefim corris<br />

de vertice dekripta fuit, vel ane<br />

appulfium ejus ad verticem defcribenda<br />

ek lnnotefcit quantitas arez il-<br />

Bins abfcinde.nda: ex tempore ipfi proportionali.<br />

Bikca AS in 6, erigeque<br />

perpendiculum G H equate 3 M, &<br />

Circulus centro N, interval10 H S<br />

defcriptus fecabit Parabolam in loco<br />

quaefito fp. Nam, demifi ad axem<br />

,:perpendiculari T 0 & duEta !I’H, cfi<br />

AGg+GHq(=HTq=AO - A G : pad + !FGFCG-lT : pd. )=<br />

&I +TOq- 2&40-2GHx ‘PO .+AGq -WHya Urn...<br />

z~ 9-r @Q (=AOq+T,Oq-2GAO) =AQq+$‘=+<br />

TOfjf<br />

Pro AOq fixibe A’0 x TAX- 5 &, applicatis termih omnibus ad<br />

3TOduRijrqueinzAS,fiet:GHXAS(=~AOXTO-CtASXTO<br />

ZE. A”4-3~~TO= *<br />

6<br />

=areae .ZTS, ScdGHerat3”M, &inde$GHX/Seit4ASXM. 1<br />

Ergo area abfiiira AT Saqualis et-? abkindendz 4 AS X M. L&E.?.<br />

Curol. I. Hint G H eit ad A$, ut tempus quo corpus dcfcrlpfir<br />

arcurn RF ad tempus quo corpus defcripfit arcum mter verb<br />

,cern A & perpendiculum ad axem ab umbilico S ere@um.<br />

4A073.SQx l)Ozzareg/i’ApO-S’P 0)<br />

c=or~L 2. Et Circulo AST per corpus motum T perpetuo Era@-<br />

-eunte, velocitas pun&i N efi ad velocitatem quam corpus hbulr<br />

I? in


I<br />

1) E AjO T U in vertice A, UC 3 ad 8; adeoque in ea etiam ratione efi linea G H<br />

“oi”onva’ ad lineam retiam quam corpus tcmpore motus fui ab A ad T, ea<br />

cum velocitare quam habuit in vertice A, defcribere poffet.<br />

coroz. 3, Hint etiam vice verfa invenjri pptefi tempns quo corpus<br />

dekrrpfic arcum quernvis aflignatum AP.. Junge A&P & ad<br />

medium ejus pun&urn erige perpendiculum r&z<br />

.<br />

G H occurrens<br />

in H.<br />

lntra Ovalem dctur punRum,quodvis, circa quad cw ,polum‘rea<br />

voivatur perpetuo linea re&a, uniformi cum motu, & interea in rec.-<br />

ta illa exeat pun&urn mobile de polo, pergatque femper ea cum<br />

velocitate, qua2 fit ut re&az i&us intra Ovalem quadraturn. HOC<br />

motu pun&urn illud defkribet Spiralem gyris in finitis. Jam ii are=<br />

Ovalis a re&a illa abfcifk incrementurn per finitam Equationem<br />

inveniri potefi, invenietur etiam per eandem zquationem difiantia<br />

puntii a polo, quaz huic aren: proportionalis eit, adeoque omnia<br />

Spiralis pun&a per zquationem finitam inveniri pofknt: &Z<br />

propterea re&ta: cujufvis pofitione darz interfe&io cum Spirali invcniri<br />

etiam potefi per aequationem finiram. Atqui re&a omnis<br />

infinite produ&a Spiralem fecat in pun&is numero infinitis, & azquatie,<br />

qua interfeRio aliqua duarum linearurn invenitur, exhibec earum<br />

interfe&iones omnes radicibus totidem, adeoque afcendit ad<br />

tot dimenfiones quot funt interfe&iones. Quoniam Circuli duo fk<br />

mutuo fecant in pun&is duobus, interfk&o una non invenietur<br />

nifi per zquationem duarum dimenfionum , qua interfe&io altera<br />

etiam inveniatur, Qonram duarum fifiionum Conicarum qua&r<br />

effe pofl?lnc interfe&iones, non potef? aiiqua earum generaliter iqvelziri<br />

nifi per aquationem quatuor dimenfro qua omnes iimu1<br />

inveniantur. Nam ii interfe&iones ilk fro quazantur, quo-<br />

LE omnium Zex & cqnditio, idem calculus. ..in cafe<br />

propterea eadem @tilper cone! qw Q$p-. de-<br />

* bet ornnes interfe&iones fimul’c~~.ple&i & mdi#Ferenter exhibere.<br />

.,*.:<br />

,I<br />

-I._i,”,.)<br />

L’ Waade<br />

,<br />

‘A..:-,<br />

.I<br />

. T. 9’ 1<br />

.


de km ~merfettiones Se&ionum Conicarum cy= CurviIrum EGTI :.1 ~<br />

potefiatis, eo quod kx eire poffunt, Gmul prodeurlr pcr LriiIIJ- I> I<br />

knes fex dimenfionum, 8r interfe&-ioncs duarum Curvaru~~, tcTr;s<br />

Potefiatk quia novem e@ pofiunt, fimul prodeunt per ;ycI!IJtiones<br />

dimenfionum novcm. Id nifi necerario fieret, reduccrc irceret<br />

Probfemata omnia Solida ad Plana,& plurquam Sol:dtn aci SO1a.,<br />

da. Loquor hit de Curvis poteitate irrcducibilibus. N~II~ ii X9Lt2-<br />

eio per quam Curva definitur, ad inferiorem porc/tatcm reJ:lci<br />

pofit: Curva non erit unica, fid ex duabus vcl pluribus c~~~pu~i...<br />

ta 3 quarum rnte&&ones per calculos dwcrfos korl;m inveiBiri<br />

@offunt. Ad ewndem modum interkLtiones bins refiarum z< fEi?ionum<br />

Conicarum prodeunc kmper per 6zquationes duarum ciin?crlfionum<br />

5 terna: re&arum & Curvarum irreducibilium terris potcitlatis<br />

er azquationes trium, quaternz re&arum & Curvnsum irrcducibi-<br />

urn quartz potefiatis per aquationes’dimenfionum quatuor, b (ic<br />

In infinitum. Ergo reQiz 8-5 Spiralis interi”eCciones numero iflfinit;~.‘CJce~n8<br />

Curva haze fit fimplex & in Curvas plures irreducibilis, requirursc x.-<br />

quationes numero dimenfionum & radicum infinitas, quibus om ncs<br />

nt fimul exhiberi. Efi enim eadem omnium lex ik idem calculus.<br />

ii a polo in re&am illarn kcantem demitcatur pcrpendiculum,<br />

& perpendiculum iilud una cum f&ante revolvatur circa polum, interk.&iones<br />

Spiralis tranfibunt in fe mutuo,quaque prima erat k~z<br />

grqxima, poit unam revolutionem iecunda crit, pa!.3 duas tertk<br />

8r’ %c deinceps : net interea mutabitur aquatio nifi promutata magnitudine<br />

quantitatum per quas pofitio kcantis dcterminatur. U&e<br />

cum quantitates illa: pofi fingulas revolutiones aedeunt ad magr~iandines<br />

prImas,. zquatio redibie ad formam primam, adeoqw u:~:~<br />

&=mque exhibebit interfe&iones omnes, k propterca. radices bahit<br />

numero infinitas, quibus omnes exhiberi p~fht. xcquic<br />

ergo interfe&io re&az & Spiralis per zquationem fikm generaliger<br />

inveniri, & id&o nulla extat Ovaiis cujus area, rcfiis impcratis<br />

abfcira, pofit per talem Equationem generaker cxhiberi.<br />

Eodem argumentotYi intervallum poli & pun&i, qu? Spirnlis debitur,<br />

capiatur Ovalis perimetko abf’kiffk proportlon& prod<br />

i potefi quod longitudo perimetri nequie per finitam zquationem<br />

generaliter exhiberi. De Ovalibus autem hit loquor qu:r non<br />

tanguntur a figuris conjugatis in infinitum pergentibus.


P<br />

100 . r<br />

Da Moru<br />

CUUPOUUM<br />

Corollarium.<br />

Wine area Ellipfeos , qua: radio ab umbilico ad corpus 9obiIe<br />

du&to defizribitur , non prodit ex dato tempore, per zequatlonem<br />

finitam; st ropterea per defcriptionem Curvarum Geometrrce rationalium<br />

J eterminari nequit. Curvas Geometrice , rationales aqpello<br />

quarum puntia omnia per longitudines z,quationrbus de.finl:<br />

tas, id efi, per longitudinum rationes complrcatas3 cY!etermxnan<br />

poffunt 5 cxtcrafque (ut Spirales, Quadratrices, Trocholdes) Gee.-<br />

metrice irrationales. Nam longitudines qw lint vel non funt ut<br />

numerus ad numerum (quemadmodum in decimo ~l~ementorum)<br />

funt Arithmetice rationales veI irrationales. Aream lgitur E!lipfeos<br />

tempori proportionalem abfcindo per Curvam Geometrlce lrratwaalem<br />

ut Irequitur,<br />

Ellipfeos ~$23 ~3 fit A vertex principal& S umbilicus, 8~ 0’<br />

centrum, fkque P corporis locus inveniendus, Produc Qd ad G,.<br />

IIF fit 0 G adOA ut O.&ad 0 S. Erige perp


CP<br />

E<br />

G Ic’ in ratione ad Rota: perimetrum GE FG, ut LtBER<br />

efi -ternpus quo corpus progrediendo ab A defcripfit arcum AT, ad I-J RI M vi”<br />

rempus revolutionis unius in Eilipfi. Erigatur perpendiculum K L<br />

occurrens Trochoidi in L, & a&a L T ipG I( G parallela occwxt<br />

Ellipfi in corporis loco qwfito P.<br />

Nam centro 0, intervallQ 0.4 defcribatur fimicirculus R.gB,<br />

& arcui A&occurrat LP produaa in g,.junganturque S&O $&<br />

.,&cui E FG occurrat ORin F, & ineandem Ogdemittatur peryendiculum<br />

S R. Area A PS efi ut area A.&S, id efi> ut diffe;<br />

rentia inter ie&orem 0,&!&A & triangulum 0 RS, five ut differentia<br />

reQangulorum :O,$&xAE& iO&x5'R, hoc e&.ob datam.<br />

3 0 &?V& ut differentia inter arcurn A&& reQam S R,adeaque (ob<br />

aequalitatem datarum rationum SR ad finurn arcus A& 0 9 ad 0 A,<br />

(j Aad 0 G, A&d G F, & divifim AeS.R ad G F-fin, arc.AZQ<br />

ut G K differentia inter arcurn’ G F & hnum arcus A& &QE. D.,<br />

zterums. cum difficikfit hujus’Curva defcriptio, pm&at folu~<br />

nem vero proximam adhibere. Inveniatur turn angulus quidam-<br />

) qui fit ad angulum graduum 57,29$78. quem arcus radio azqualis,<br />

fibtendit, ut eit umbilicorum difiantia SH ads Ellipkos diamw<br />

trum A B 5 turn etiam longitudo quedam L, qua fitad radium in:.<br />

eadem ratione inverfe. Q$bw el inventis, Problema deinceps I<br />

confit per kquentem AnaIyGn. r confiru&ionem quamvis .(vek.<br />

utcunque conjecturam<br />

faciendo )”<br />

cognofkacur corporis<br />

locus T proximus<br />

vero ejus locog.DemiKaque<br />

ad:<br />

axem Ellipfeos ordinatim<br />

applicata<br />

P 2% ex proportione<br />

diametrorum<br />

applicata R &qua? finus e! anguli $0 &xi-<br />

SufFicit angulum illum rude calculo mnumeris .’<br />

proximis invenire, ognofcatur etiam angulus tempori propo+:<br />

tionalis$,


102 . P’HI:LOSOPMIE NA RAEIS<br />

DE MoTu tionalis, id efi, qui fit ad quatuor re30sj u tempus quo corpus<br />

c ORPOKU hl deriripfit arcum Ap9 ad tempus revolutionis unius in Ellipfi. Sit<br />

angulus i&z N. Tum capiatwr & angulus D ad angulum B, ut<br />

eit finus ilte anguli A02 ad radium, & angulus E ad angulum<br />

N -AO &+ I), UC eit longitude L ad longirudinem eandem L<br />

CO~U anguli A 0 g diminutam , ubi angulus ifie re&o minor eft,<br />

au&m ubi major. Poitea capiatur turn angulus F ad angulum B,<br />

ut efi finus anguli AOg+ E ad radium, ‘turn angulus G ad angulum<br />

N-AOg- E +F ut eit longitudo L ad Iongitudinem eandem<br />

CO~~IILI anguli A0 $&+ E diminutam ubi anguIus ifie re&ominor<br />

efi, au&am ubi major. Tertia vice capiatur anguIus ff ad angulum<br />

B, ut efi Gnus anguli A0 g+ E + G ad radium 5 & angulus<br />

I ad angulum N-AOR-- E - G $Ws ut efi longitudo L ad<br />

eandem longitudinem cofirm anguli A 0 g + E + G dimiautam,<br />

ubi angulus ifie re-<br />

Qo minor efi, auctam<br />

ubi major. Et<br />

fit pergere licet in<br />

infinitum. Denique<br />

capiatur angu-<br />

IUS AOq aequa!is<br />

angulo A 0 R+ E<br />

+G+I+ &cm e t<br />

ex cofinu ejus Or<br />

& ordinatap r,quz<br />

eit ad finurn ejus A.<br />

qr ut Ellipfeos axis minor ad axem majorem, habebitur corporis<br />

locus correkus p. Si quando arigulus N - A 0 R+ I.3 negarivus<br />

efi, debet Signum +ipGus E ubique mutari in -, & Signum- In-/-. ’<br />

ldem intelligendum efi de fignis ipforum G & 1, ubi anguli<br />

N-AO~--EEFF, &N -AOR-E-G+H negativiprodeunt.<br />

convergic autem &es infinira A 0 g-+ E + G + I + kc. quam<br />

celerrime, adeo ut vix unquam opus fuerit ultra progredi quam<br />

ad terminus kcundum E. Et fundatur calculus in hoc Theorem<br />

mate, quad area A T S fit ut differentia inrer arcpm A $&<br />

r&am ab umbilico<br />

miffam.<br />

S in Radium 0 R perpendicuIariter de-<br />

Non difimili calculo .con,fkitur Problema in Hyperbola. Sit<br />

ejus ~entrurn.0, Vertex A, Umbilicus S & Afymptotos Q K. Cognofcatur


INC<br />

log<br />

llofcatur quanti!as arex abfcindendz tempori proportio~alis, sit ea<br />

l,I BL’R<br />

A, & fiat con@ura de pofitione re&a s p. qurr: aream AT s P u r t4U Sa<br />

abkindat vera proximam. Jungatur<br />

0 P3 & ab A & T ad<br />

~fymptoton agantur AP; T IC<br />

Afymptoto alteri parallek, & per<br />

‘I’abulam Logarithmorum dabitur<br />

Area A.TK P, eique xqualis<br />

area 0 PA, quz fkbdu6k-a de triangulo<br />

0 P Srelinquet aream ablfciffam<br />

AfPS. Applicando are=<br />

abfkindendz A & abfiiffa: RT J’ o<br />

differentiam duplam z A T&-z A<br />

vel z A- z A*P S ad Iineam SN, qua ab umbilico S in tangentem<br />

P T perpendicularis eR, orietur longitudo chords Tg Infcribatur<br />

autem chorda illa I> Einter A & P, fi area abkiffa AT%<br />

major fit area abfcindenda A, fetus ad pun&i T contrarias parks:<br />

& pun&urn q erit locus corporis accuratior. Et computatione<br />

rep&a invenietur idem accuracior in perpetuum.<br />

Atque his calculis Problema generaliter confit Analytice.<br />

rum ufibus Afironomicis accommodatior efi calculus particu<br />

qui fequitur. Exifientibus .40, 0 Bs 0 23 kmiaxibus Ellipkos,&<br />

L ipfius latere re&o, ac D diff’erentia inter femiaxem minorem 0 ‘2p<br />

& lateris re&i iemiffem f L j quare turn angulum Y, cujus fifwfit<br />

ad Radium ut efi re&angulum<br />

f’ub difl’erentia illa D, &<br />

km&mma axium A0 + 0 2;,<br />

w<br />

ad quadratum axis majoris AB ;.<br />

fum angulum 55, cujus finus<br />

fit ad Radium ut efi +pIuk<br />

re&angulum fub urn bilicoruq<br />

difiantia S 23 k difFerentia<br />

illa D ad triplum quadrarum A s 0 H 13<br />

fimiaxis majoris n 0. His.<br />

angulis fkmel invenris j locus corporis fit deinceps dkterminabitur.<br />

Sume angulum T proportionalem tempori quo arcus B ‘F defcriptus<br />

e& ku motui mcdio ( ut loquuntur ) aqualem j & at~guld~~:<br />

V ( primam medii motus xquationem) ad angulum Y (azqu$onem<br />

maximam primam) ut efi finus dupli anguli T ad Radmm I.<br />

,atque.


3! ok+ P~HILQSQPHIfi ~T’~~~~~<br />

DE MO TU atque. angulum X (zequationem kcundam) ad angulum 2. (gquas<br />

cQRPoRU~ fionem maximam fecundam) ut efi cubus hus angull T ad cubom<br />

Radii. AnguIorum T, V, X vel fummz T + X + V3 ii angulus<br />

T,retto minor efi, vel differencia T +X - V, fi is re&o major eit<br />

reC5ticque duobus minor, zqualem cape angulum B HT (mo#3,&l<br />

medium azquatum ; ) &, fi H T occurrat Ellipii in T, a&a J’P ab-<br />

.fcindet aream B ST tempori proportionalem quamproxime. Wac<br />

Praxis fatis expedita videtur,<br />

propterea quod anguloru? perexiguorum<br />

V Sr X (in mlnutis<br />

i<br />

D<br />

z<br />

:Skcundis, li placer, pofitorum)<br />

!<br />

:<br />

.figuras eduas terfve primas invenire<br />

rufficit. Sed & fatis accuraca<br />

eit ad Theoriam Planetarum.<br />

Nam in Orbe vel Martis<br />

ipfius,cujus Equatio ten tri ma- A S I-1<br />

xima elt graduum decem, error<br />

vix fuperabit minutum unum<br />

fecundurn. Invent0 autem angulo motus medii zquati B HP, an-,<br />

gulus vcri moeus BST & difiantia ST in promptu funt per<br />

IYardi methodurn noti0imain.<br />

Ha&enus de Motu corporum in lineis Curvis. Fieri autem poteft<br />

UC mobile reLZa dcfiendat vel re8-a afcendat, & quz ad ifiiufi<br />

modi Motus fjeflant, pergo jam exponere.


XII. PROBLE,,IA XXI-V,<br />

4%. I, Si Corpus non cadit perpendicu-<br />

Iariter defcribet id, per Coral. 1. Prop. XXII,<br />

Se&ionem aliquam Conicam cujus umbilicus<br />

congruit cum centro virium. Sit] Secaio<br />

illa Conica AR PI3 & umbilicus ejus S.<br />

Et primo ii Figura EllipGs efi, f@Fr hwjus<br />

axe maSore AB defcribatur Semrcwculus<br />

RD 23,’ & per corpus decidens trankat rec-<br />

ta 23 T C perpendicularis ad axem; a&ifque<br />

93 8, T S erit area ASZ) are= ASP atgue<br />

.adeo etiam tempori proportionalis. h/lanente<br />

axe AB minuatnr perpctuo latitude<br />

EIIipCeos, & kmper manebit area A S I><br />

tempori proportionalis. Minuatu! latitude<br />

illa in infinitum: &, Orbe APB jam corncidente<br />

cum axe AB & umbilico S cum<br />

axis termino B P defkendet- corpus in retia<br />

~- _<br />

AC, & area AB “u evadet temporl progortionalis.<br />

Dabitur itaque Spatium A. C9<br />

quad corpus ,de loco A perpendicularlter<br />

cadendo tempore data dek-ribit, fi mode tempori proportiona-<br />

Bis capiatur area A.,B 59, &.I a pun&o D ad re&am A B den+<br />

~atur perpendicularis DC. Z&E. I.


1 sG Y’HILOS~D~~I~ %!A<br />

11 E LYI cl ‘r u ~2s. 2, Si Figurn illa RT B Hyperbola efi, defcribatur ad ease;<br />

i~YoR*‘VRUbI dcm diametrum principalem A B Hyperbola re&angula. B Z;: D :<br />

& quoniam arcz CR?, CBf P, SPf B finr ad areas CSDa<br />

cfi ED, S’D ER, fingul~ ad Gng&, in data ratione akit&=<br />

num CP, C’D j & area S’PfB<br />

proportionalis cfi tempori quo<br />

corpus T movebitur per arcum<br />

(Pf B; erit etiam area SWEEB cidem<br />

tempori proportionalis.<br />

Minuatur Iatus r&urn Hyper- ’<br />

bolz R T B in infinitum mancnre<br />

here tranfverfo, & coibit<br />

arcus 2) B cum reQa CB & urnbilicus<br />

S cum verrice B & relfta<br />

.:*<br />

Sfl, cum r&h BD. Proindc a-


~~~~CN?IA MAATHE~A-~IcA. 107<br />

ham fecet communemillam diametrum AB (fi opus ee prod~~~;am:; L I 8 ? x<br />

in 7; fitque S Tad hanc retiam, & B$&ad ‘si;,,<br />

E’ x : rl ” SE<br />

hanc diametrum perpendicularis, atque Figu- ::.<br />

rz R TB htus re&um ponatur L. Conftat t..,<br />

per Car. pg Prop, XVI, quod corporis in !.,.<br />

hea RPB circa centrum S moventis velo- !,<br />

citas in loco quovis T fit ad velocitatem COC- / I.<br />

poris intervallo ST circa idem centrum Circulum<br />

deh-ibentis in fiubduplicata ratione recrtanguli<br />

5 L xST ad STquadratum. Efi autern<br />

ex Conicis ACB ad CT 4 ut z A0 ad L,<br />

ST94 x A0<br />

adeoque<br />

zquale L. Ergo ve-<br />

ACB<br />

locitates illa funt ad invicem in fubduplicata<br />

CTqxA OxST<br />

ratione<br />

ad STqwd Por-<br />

ACB<br />

ro ex Conicis efi CO ad 230 ut B 0 ad TO,<br />

& compofite vel divifim ut CB ad B T.<br />

Unde vel dividend0 vel componendo fit<br />

BO-vel+CO ad BO ut CT ad ST, id eft<br />

CTqXAO)(SP<br />

ACadAOutCTadB~jindeque<br />

aquale et?<br />

ACB<br />

J3gq x ACxS~ Minuatur jam in infhitum Figura R PB latitu-<br />

AOxBC’ -<br />

do CT, fit ut pun&urn T coeat cum qnn3.o C, pun&umque Scum<br />

pun&o & 8.z linea ST cum linea f c) lu?eaque S I’ cum !inea B &,<br />

a corporis jam re&a defcendentrs in lmca CF velocltas Fet ad<br />

velocitatem corporis centro B intervallo B C Grc,ulum,defccnbentis,<br />

BL$q xACxS*P<br />

in fibduplicata ratione ipIius<br />

-adSQ,hoceit(neg-<br />

AOxBC<br />

leeis aqualitatis rationibus ST ad B C 8c BZQ ad STq) in fubduplicata<br />

ratione AC ad A0 five.$ AB. A& ~5, 59.<br />

Coroj, I, Pun&is 23 & S cowntibus:, fit TC ad TS ut AC<br />

id AO.<br />

duplam<br />

1 &&, 2’. Corpus ad &tam a centro difiantiam in Circulo quo-<br />

+is revolveng hotu {IO furfim verfo afkendet ad<br />

centro dtiantiam. ,: :,j<br />

Pz<br />

FROPO-<br />

ham a


IGQ ~H~EOSOPHI~ NATURALIS<br />

I>f. h'!OTU<br />

C~liPORUhS PROPOSIT~O XXXlV. THEOREMA X.<br />

Si fip~a B E D Pmdbojld e/!, dko<br />

good cu~potir cud&s<br />

C~WO<br />

Velocitbrs<br />

in ho quo;vis c qudi.f qz<br />

q;eIocitnti qu corpw B<br />

p0td-L<br />

dhzh?o Plltewallifui B C Cir-<br />

CZ&‘UUZ uniformiter d$cribcre<br />

Nam corporis ParaboIam-<br />

I? FB. circa centrum S defcribentis<br />

velocitas in loco quovis<br />

T ( per Coral. 7. Prop, XVI) Z-<br />

qualis efi velocitati corporis di+<br />

midio intervalli ST Circulum circa<br />

idem centrum S uniformiter<br />

defcribenhs. Minuatur farabolx<br />

latitude C?? in infinitum eo> ut<br />

arcus Parabolicus Tf B cum recta<br />

CB, celltrum S cum vertice B,<br />

& intervallum. ST cum intervallo B C coincidat, 8~ confiabit Prp<br />

politio, 4 E, I).<br />

P-R0POSITIO XXXV. THEOREMA: XL.<br />

N~III eoncipe corpus C quam minima eernpori’s partkula lineofan<br />

C’s cadendo defcribere, & interea corpus aliud K3 uniform&<br />

ter in Circulo 0 .K k. circa centrum. S. gyrando, arcum KR de&ihere..<br />

Erigantu,r perpendicula C I>, c d occurrentia Figurzz ,m 25 S<br />

in 2), d. Jungantur SD, Sd, SK, Sk & ducatu;. “D.d axi .A.$ ochens<br />

in TI Sr; ad earn demittatur perpendiculum ST:<br />

‘* , cafi


~46 1. Jam fi Figura 2) ES Grcuhs efi vel Hyperbola, birece-<br />

L InEt<br />

tur’ejus tranfverfa diameter AS in 0, Sr: erit<br />

PRIMU E*<br />

J 0 bimidium lateris reQi. Et quouiam efi A<br />

TC ad 71) utCcadD& & T”W adTSut<br />

C D ad ST, erit ex xquo T C ad TS ut<br />

C!DXCC ad STxZId, SedperCorol. r.Prop.<br />

XXXIXI~ eft TC ad %S ut AC’ ad A03 puta fi<br />

in coitu pun@corum D, d capiantur linearurn<br />

rationes ultima. Ergo AC elt: ad (A0 f&)J’K<br />

ur C 59 x Cc ad S I+ x 59 d. Porro corporis<br />

dehndentis velocitas in C efi ad velocitacem<br />

corporis Circulum interval10 SC circa centrum<br />

S dei‘cribentis in fubduplicata ratione<br />

AC ad (A 0 vel) SK (per Prop, xxxxlI.) Et<br />

IXEX velocitas ad velocitarem corporis defiribentis<br />

Circulum Q Kk in fubduplicata rarione<br />

S .K ad SC per Cor. 6. Prop. 1 v, & cx xquo V~Ocitas<br />

prima ad ultimam, hoc eR lineo!a Cc ad<br />

arcurn J


DC hloru<br />

CorroRuM<br />

i?ROPQSITI’O XXXVI. PROBLEMA xX=$?<br />

~~pris de ho data A dentis determinare Temporn<br />

deJcexJtis.<br />

Super diamccro AS (diftantia corporis a centro<br />

filb initio j dcfcribe Scmicirculum AD S, ue 8r<br />

huic xqualem Semicirculum 0 K H circa centruQ<br />

S. De corporis loco quovis C erige ordinatim applicatnm<br />

CD. Junge $9, & are= A SD xqualem<br />

conftitue fe&orem 0 S K, Patet per Prop.<br />

xxxv3 quod corpus cadendo dekribet fpatium AC<br />

codem Tempore quo corpus aliud uniformiter cir&<br />

ca centrum S gyrando, defcribere po tefi arcum<br />

OK. SE. F:<br />

Exeat corpus de loco dato G Eecundum<br />

lineam ASG cum velocimte quacunque.<br />

In duplicata ratione hujus velocitatis ad<br />

uniformem in Circulo velociratem, qua corpus<br />

ad in tervallum datum 5’ G circa ten trum<br />

S revolvi poifet , cape GA ad 5 A S.<br />

Si ratio illa eit numeri binarii ad unitatern,<br />

punfium A infinite dikt, quo ca-<br />

Si Parabola vertice 8, axe SC, latere quovis<br />

retie dekribenda elt. Patet hoc per<br />

Prop. xxxw. Sin ratio illa minor vel major<br />

efi quam z ad I~ priore cafu Circulus,<br />

pofieriore Hyperbola reQangula lizper diametro<br />

S A dekribi deber. Patee per<br />

.Prop. xxx1 II, Turn centro J’, intervallo<br />

zquante dimidium lateris re&i, defcribatur<br />

@ircuIus H-K’,& 8t ad corporis afiendentis<br />

vel defcendentis loci duo quzvis G,C,<br />

xrigantur perpendicula G I, C’il) occurrentia<br />

Conic&eQioni vel Circulo in I ac 21.


ein jun&iS S 6, S 57, fhnt fegmentis SE IS, SE23 S, feel<br />

tares HSK, HS k XqUil’eS, & per Prop. xxxv, corpus G defrri- PLK:i’th<br />

bet fpatium G C eodem Tempore quo corpus X dekribere potefi<br />

arcum KR. S&E, 8’.<br />

Cadat corpus de loco quovis R iixundum<br />

reQam ASj & ceutro virium S, intervallo<br />

AS, defiribatur Circuli quadrans<br />

A E, fitque CD finus re&us arcus cujufiris<br />

AD j St corpus A, Tempore AI), ca-f<br />

dendo defcribe!: Spatium AC, inque loco,<br />

C acquirer Velocitatem CB.<br />

Demonhatur eodem modo ex Propofitione<br />

x1 quo Propofitio XXXII, ex Propofitione<br />

XI demo&rata fui t.<br />

curol. I’. Hint xqualia Gun t Tempora quibus corpus unum de loco<br />

A cadendo pervenit ad centrum S, & corpus aliud revolvendo dehibit<br />

arcum quadrantalem AD E.<br />

Cwol. 2. Proinde zqualia fiint Tempora omnia quibus corpora de<br />

locis quibufvis ad urque centrum cadunt. Nam revolventium tenaP<br />

pora omnia periodica (per Carol. 3, Prop. IV.) zquantur.


-I 1 $2 P~HIUXKH'H~~ NATURALIS<br />

BrMoru<br />

COLPORVH ~fROPOSlTI0 XXXIXe PROBLEMA XXVII:.<br />

De 10~0 quovis A in retia A?D E c cadat COFPuS E, deque loco<br />

ejus E erigatur fernper perpendicularis<br />

quam<br />

EG, v1 c~~~tripet~ in lQC”<br />

ill0 ad centrum C tendenti proporh<br />

nalis: Sitque B FG linea curva<br />

pun&am G perpetuo tangit. CoincL<br />

dat autem E G ipfo motes initio cum<br />

perperldiculari AB, & erit‘corporis Ve-<br />

Iociras in loco quovis E ut area curvihez<br />

AB G E latus quadratum.<br />

&E. I.<br />

In E G capiatur EM Iateri quad&-<br />

‘to are2 AB G E reciproce proportionaiis,<br />

& fit AL M linea curva quam<br />

pun&urn Mperpetuo tangit,& erit Tempus<br />

quo corpus cadendo defcribit Iineam<br />

A E ut area curvilinea AL ME.<br />

$i$ Es 1.<br />

Etenim in reQa AE capiatur linea<br />

quam minima 53 E data longitudinis,<br />

Gtque D L F locus line= E NG ubi<br />

corpus verfabatur in D ; & fi ea fit vis centripeta, ut arez AB GE<br />

Hiatus quadratum iit yt defcyxlentis velocitas, erit area ipfa in drrplicata<br />

ratione velocltatis, id efi, ii pro velocitatibus in 3 & .B<br />

fcribantur V & V +I,erit area AB FD ut VV, & area ABGE ut<br />

VV~+~Vh-~L &I divifim area ZW'GE ut 2 VI +II, a&oque<br />

ZIFGE zVl+Ii<br />

DE “-7XE ----3 id efi, fi prims quantitatum naTcentium<br />

raciones fumantur, Iongitudo 2) F ut quantitas - 2vx -<br />

$ adeoque e-<br />

DT ’<br />

.$arn ‘ut qrrantitatiS hujus dimidium IXV<br />

DE”<br />

autem tempus 9~0<br />

corpus


PRI~CIl?IA<br />

MATHEMATICA,<br />

115<br />

CQrpus cadendo ckfiribit Iineolam I) E, ur heola illa dire+ e: ?,, I tK<br />

.velocitas V ilIver& efique vis Ut Velocitatis incremencum 1 dir&c Px i w ill.<br />

&‘%m~Pus inverk adeoque fi primx nafcentium rationcs fim~an-<br />

tur:, ut $j-$ 3 h 0~ efi, ut longitudoB3’. Ergo Vis ipfi DE vcl~~<br />

PrOpOrtiOna~is facit ut corpus ea cum Vclocirate def&dar quz fir<br />

-ut area: AB GE latus quadratum. &E. 2).<br />

Porro cum ternpus, quo quxlibet longitudinis datrt: linc& DE<br />

defiribatur, fit ut velocitas inverk adeoque ut ares ABFZ) laclls<br />

quadratum inverfi j fitque 92 L, acque adeo area nafcens 2, L~JE,<br />

ut idem laws quadraturn inverfe : crit cempus UC area 9 L JfE, k<br />

4bmma omnium temporum ut fumma omnium arearum, hoc eft<br />

(.per &rol. Lem. xv) Ternpus torum quo linea AE del‘cribirur LX<br />

area tota AM E. .& E. 5%<br />

C?WPI. F; Si T fit locus de quo corpus cache debet, ut, urgente<br />

aliqua utliformi vi centripeta llota (qualis vulgo i‘upponitur<br />

Gravitas) velocitatem acquirat in loco *D zqualem veiocitnci<br />

quam corpus aliud vi quacunque cadens acquifivir eodem locoD,<br />

& in perpendiculari DF capiatur 13 Ai, qux Gt ad I) F UC vis illa<br />

uniformis ad vim alteram in loco 53, & compleatur reflangulum<br />

‘2 2) R & eique aqualis abfcindatur area A B FqD 5 erit A locus<br />

de ‘quo corpus alterum cecidit. Namque corn Ieto rcfian@o<br />

99 .R S E, cum fit area ABFD ad aream D P GE ue V Icf ad<br />

z V I, adeoque ut IV 1 ad I, id eR, ut femifis velocitatis totius<br />

ad incrementurn velocitatis corporis vi insquabili cadentis; & iimiliter<br />

area T E&f 2) ad are;am ?>$?I?,!? ut fern& velocitaris totius<br />

ad incrementurn velocltatis corporis uniformi vi cadentis,<br />

fintquc incrementa illa (, ob zqualitatem temporum nafcentium ><br />

ut: vires generatrices, id efi, UC ordinarim ap,plicatx ?) Fj ‘D-k<br />

zquan<br />

adeoque ut.are= nafcenres fD FG E, 2) R S P: 5 erunt (ex zc1UO)<br />

arek tota: 19 BFD, T ,&3R D ad invicem ut kmiifes totarum ve-<br />

10Clt~tUIl~, & propterea (ob squalitatem velocitarum)<br />

coral. f Unde fi corpus quodlibec de loco quocullquc ‘II data<br />

cum veloeitate vel furlrum vel deor&m projiciatur, 6r dctnr Icx vis<br />

centripetg, invenietur velocitas ejus in alio quovis loco Ed erigendo<br />

ordinatam eg, & capiendo velocitatem illam ad VehitaWm in<br />

loco 2) ut ee latus quadraturn rc&anguli T 2 I? 9 area curvihnea<br />

59 Fg e vel au& c locus e e5 IOCO 7) inferior, 1x1 diminu$<br />

G is Cuperior efi3 a d latus quadrarum rehanguli fobs *P&J “D, Id<br />

---<br />

e~,ut 4 ~p~Zt~+veI--‘D F@ ad JFS?$ De<br />

Carol.<br />

Q


1x4 PHIL~~~PHI~~ NATURALN /<br />

1jE &~liioTU Coroj. 3, Tempus quoque innoteflcet erigendo ordinatam em re- ’<br />

C~R~ORUS ciproce p~o17ortiodem lateri quadrato ex T’RR D+vel--22 $“g 6,<br />

& capicndo rcn~pus quo corpus defcrlpfit lineam De ad temptis<br />

quo corpus altcrum vi unitiormi cecidit a T & cadendo pervenit ad<br />

“D, UC area curvi3inen 53 t m e ad reQanguIum t T D x I) I,. Nrrriquc<br />

tcmpus quo corpus vi uniformi defcendens de&ripfit: heam<br />

;~u”I) efi ad ternpus quo corpus idcm dekripfit lineam ‘PE in fubduplic;lta<br />

rationc P‘SB ad FE, id efi (lineola 2) E jamjam nafcentcj<br />

in mionc F2) ad PD-++ DE feu zPD ad zTD+D.Ep<br />

&z’ divih~, a,d cempus quo corpus idem dekripfit lineolam DE<br />

LIS 2 P 59 ad ‘9 E9 adeoque ut re&angulum 2 T ‘B x “%, L ad aream<br />

I) L LU,E ; eiique tempus quo corpus utrumque defcripiit linedlam<br />

‘27I E ad rcmpus quo corpus alterum in;equabili mdtu dekripc<br />

fit lineam I) e u t area D L ME ad aream ‘33..L me, & ex aqua<br />

tcmpus primum ad tcmpus ultimum ut re&angulum t TtD xfo L.<br />

ad aseam 53 L me.<br />

IIt ff-2~2tio72e, Orbiurn in quibas corporu Yiribus guibufcmqtie cem- /<br />

trip&s agituta vevohuntur.<br />

i<br />

i<br />

PR,OPOS:+I’IO XL. TWEOREkfA XIII. /<br />

Si ~0rpf.0, cogem Vi guacmqtie cefihpeta,<br />

mweatur utcunque, &<br />

GOrpUS ahdrefiia ascendat wEdeJce&zt, Jintpe eorum Vekocita~<br />

tcs in alipo quakwn ulti~udinum taJ4 &pales, Yelocitates eor#m<br />

Z+J onmibm qualibus altitz4dhihs ersknt quakes.<br />

Defcendat corpus aliquod ab A per ‘D, E, ad centrum C, &<br />

moreatur corpus aliud a Yin linea curva TIKk, Centro C intervallis<br />

quibuivis dekribanmr circuli concentrici 53 I, E K ‘r&x<br />

AC in D & E, cwrveque PIK in I & K occurrenres. JGngatur<br />

IC occurrens ipfi KE in A?; & in IK demittatur perpetidiculum<br />

ATTj fitque circumferentiarum circulorum intervalhum 22 E<br />

veI Sdkr qwam minimum, &.habeane corpora in 22 & ,.I.v$oci&<br />

Itcz$


tks zquales. Qykam difitantiz CD, CI aquantur, cramt vi- I,? a;F?<br />

res centripetaz in TI & I aquales. IExponantur 1132 vircs per tt’- 4”~ J13 6.<br />

qUdM lineolas 2) E,, 1 N j Sr fi vis una IN (per Legurn Coral. 2.j<br />

refolvatur in duas .A?? & dT, vis XT, agenda feclrndunl lincani<br />

NT corporis curfui IT& perpendicularem, nil mutabic veloeitagem<br />

corporis in curfu illo, ted retrahet folummodo corpus a curfu<br />

re&ilineo, facictque ipfum de Orbis tangente perpetuo dcfle


116 rW1:IBwX’Hr~ NATURALIs<br />

DZMOTU<br />

porum velocitates in E & I! & eodem arguFento.femper reperi-<br />

COtlPORUh4<br />

entur xquales in fitbkquentibus zqualibus dhn.tns. $I& E. ‘Da<br />

Sed & eodem argument0 corpora xquivelocia & zequaliter a centro<br />

difiantia, in akenfu ad zquales. difiantias xqualiter retarda-<br />

buntur. g&E.D.<br />

&rol. T. Hint fi corpus vel fknipendulum okilletur ) Vel iTi=-.<br />

pediment0 quovis politifimo Sr perfe&e lubrico cogatur in -<br />

Thea curva move& & corpus aliud re&a afiendac vel defkendaty<br />

Gntque velocitates eorum in eadem quacunque altitudine zquale~+:<br />

erunc velocitates eorum in aliis quibukunque zqualibus altitudrni<br />

bus zquales. Namque impediment0 vafis abfolute lubrici idem<br />

przritatur quod vi tranfverfa NT, Corpus eo. “on retardatur,<br />

non. accel.eratur, Ced tanturn cogitur de curfu re&hneo difcedere.<br />

GwaL 3. Ehc etiam fi quantitas P fit maxima a centro dif%arri<br />

zia, ad quam corpus.vel oi’cillans vel in TrajeQoria quacunque rs-.<br />

volvens, dequk quovis TrajeEtorik pun&o, ea quam ibi habet<br />

velocitate furfum proje&um afiendere pofit ; fitque quantitas A<br />

difiantia~ ccwpotis .a centro in alio quovis Orbita: pun&o, & vis<br />

cestripeta kmper’ fit ut ipfius, A dignitas quaelibet An- 1, cujus.<br />

Index %-I efi nwnerus. quilibet a anitate diminutus; velocitas<br />

crrrporis in omni- altitudine. A erit ut d/Fn -An, atque adeo da+<br />

mr. Namque Lelohas re&a afcendentis ac defcendentis ‘(per. Prop.<br />

~xxxrx) efi in hat. ipfk ratione..<br />

. ..“” “‘W .<br />

.PRO;PO+.


PROI’OSLTIO XLI. PROE3LElh4A XXVIII.<br />

PKIMUS<br />

PO& c~‘~~ctingue genetis Yi ceT&$peta & conce$ts Figwwum<br />

curcvilinersriwz qtiadraturis, requirmtur turn Trajcfforif.9 in quilks<br />

corpora mozlebuntur, turn Tempera mattim in, Traje@oriis<br />

Inwntis.<br />

Tendat vis qualibet ad centrum C & invenienda fit TrajeQoria<br />

V..UKk. Detur Circulus YXT centro C interval10 quovis CV<br />

defcriptus, centroque eodem defcribantur alii quivis circuli. I’D,<br />

K.E? ‘Z”raje&oriam fecantes in J & K re&amque CV in 2> & E.<br />

Age turn reQam CN1X fecantem circulos KEY Irvin N& X9<br />

turn re&am CKT occurrentem circulo VXr in IK Sint autem<br />

pun&a 1 & K fibi invicem vicinifflma, & pergat corpus al., Yper<br />

I; T & I< ad k; fitque pun8wn A locus ilk de quo corpus aliud<br />

cadere debet ut in loco I) velocitatem acquirat aqualem velocitagi<br />

corporis prioris- in I j & fiantibus guz in Propofitione XXXIX~<br />

lineola IK, dato tempore quam minimo defcripta, erit ut velochs<br />

atque adeo ut latus quadratum are= AB FD, & triangulurn<br />

ICK tempori proportionale dabitur, adeoque &ZN erit reci-..<br />

proee ut altitudo IC, id e”; ii detnr quantltas aya Q & alti-<br />

t&o lC nominetur- A, ut x. Hanc quantitatemx rrominemus Z,<br />

8z ponamus earn effe magnitudinem iphs Q.ut* fit in aliquo,<br />

c&u, J J$BFP ad 2 UC elt: I I< ad K N, & errt ~1 omm cafu<br />

~AB.FrDadZut1Kad.iTN, &ABFD ad22 ut IKq.adKNq.?<br />

& divifim A B.FV- ZZ ad 222 ut IN qzd ad KN quad, ad-<br />

Q<br />

eoque dAB.FD-Z Z ad (Z ceu)-Iz. UP Ix ad KN, & propterex<br />

Q-xIN<br />

AxEN asquale A.BFD+2z. Unde cum TX.xXC fit..ad<br />

p;X.KNutCXgad A.& erit retianguhim. TX x x% xquale<br />

QXIXX CXguad.<br />

Igitur ii. in perpendiculo 2) J3 eapiantur-<br />

AA.+4fUW--ZZ’<br />

Q,’<br />

QX CX.t&zaR..<br />

fernper D:6, 2, ’ @iis 2 +/mFFZ;, d-z.2 a 2 A& +/&.jficjr)-z z .


1. .I $ ; _ 13. pf ‘X& 0 5<br />

.T) L h4 OT'U PU&Ia It, c perpecuo rangunr; deque pun&~ Y ad heam AC eri-’<br />

cc) RI’ORUM gatur ~~rpcnciiculum Va cl abfcindem areas curvilineas VQJ b n,<br />

,YCD cd, &r eriganrur etiam ordinataz Ex, Ex: quoniam ‘re&angLllum<br />

22 b x I x k“eu I) b x E 3squde clt dimidio re&anguIi<br />

A.x KN, lku rriar~gulo ICI


II MOT u primum urgetur in Jr, ut 2) I? ad D F. Pe<br />

I(VRUM k I cearroque C & intervallo Ck defcribatur circulus ke occurren,s<br />

r&%T?Iine, 8;erigantwrcurvarumALMm,BFGg,ab~v,8cx.~~<br />

orilinatim<br />

q$icz.itz e m> kg, e ~1, e ‘me/.<br />

Ex,dato re&angulo T fD A &<br />

dataquele<br />

e vis centri<br />

et= qua corpus primum agitatur,<br />

dantur cur-<br />

vaz linea: J<br />

FGg,<br />

A E<br />

NH, per confiruQionem Problematis xxylr,<br />

& eius Coral. I. Deinde ex dato an&o CITdatur Drondrtio naGen-<br />

tiuk IK, KN, & inde, per co&ru&ionem Pkb. ~VIII, datur<br />

quantitas Q una cum curvis lineis a b x v, d cx cw : adeoque cornpleto<br />

tempore quovis 2) b v e, datur turn corporis alcitudo Ce vel CA,<br />

turn area 2) c w e, eique azqualis Se&or XCy, anguIufque ICk &<br />

locus R in quo corpus tune verfabitur. $$ ,E. .L<br />

. Suppon!mus awem in his Propofitionibus Vim cknrripetam in<br />

recefu qwdem -a centro variari’ kcundum legem quamcunque quam<br />

quis imaginari poteR , in aequalibus autem a centro diltantiis e@<br />

undeque eandem. Atque ha&enus Morum corporum in Ckhibus<br />

immobilibus confideravimus. Superefi ut de Motu eorum in Orbibus<br />

qui circa centrum virium zevolvuntur adjiciamus pauca,<br />

.S E,C “r.1 0 --


PROPOSITIO XLITI. PROBLEMA XXX.<br />

In Orbe VT Ii po-<br />

Gone dato revolvatur<br />

corpus T pergendo a<br />

V verbs I;‘. A centro<br />

6: agatur i‘emper C#h<br />

qua: fit ipfi CT aqualis,<br />

angulumque YC p angulo<br />

.YC’F proportionalem<br />

coniUuat j & a-<br />

rea ,quam linea Cp defiribit<br />

erit ad aream<br />

VCT quam linca CT<br />

iimul dekribit, ut velocitas<br />

linez defcribentis<br />

C p ad velocitatcm line=<br />

defcribentis C P j<br />

hoc efi, ut angulus PX’p ad angulum YC??, adeoque in data rah<br />

Gone, & propterea tempori proportionalis. Cum area tempori<br />

prdportionalis fit quam linea Cp in piano immobili defcribit, manifefium<br />

eit qudd corpus, cog&re juti= quantitatis Vi centripeta,<br />

revolvi pofit ,una cum pun&top in Curva illa linea quam pun&urn<br />

idem’p ratione jam expofita defcribit in planoimmobili. Fiat angua<br />

lus FCz4 angulo 2, Cp, & linea CzJ line32 C Y, atque Figura $1 Cp 4’-<br />

guraz WCS?’ aqualis, & corpus in p femper exifiens movebieur 1~<br />

R<br />

perk-


nE MO T U perimetro Figure revolventis 21 Cp, eodemque tempore defcribet<br />

(l 011<br />

P 0 R u Xl arcum ejus f~tp quo corpses aliud ‘F’ at-cum ipfi fimilem KI zqualem<br />

VT in Figura quiefccnce VT .K defc@ere potefi, Qzratur ‘igitur,<br />

per Corollarium quincum propohtlonis VI> Viscentrlpeta qua<br />

corpus revolvi pofftt in Gurva illa linea quam pun&urn p defiribit<br />

in piano immobili, & folvetur Probtema. J& E. F.<br />

PROPOSITIQ XLIV. THEOREMA XIV.<br />

Partibus Orbis quiekentis<br />

VT, T K funto<br />

dimiles & aquale<br />

bis revolventis partes<br />

zip,p k; & punAorum<br />

T, K diitantia intelligatur<br />

effe quam minima.<br />

A pun&o kin re-<br />

&am PC demitre perpendiculum<br />

k r3 idemque<br />

produc ad m, ut fit<br />

mr ad kr ut angulus<br />

YCp ad angulum YCT. ,m rr<br />

Qoniam corporum altitudines<br />

TC & p C,KC<br />

. & kC femper zqwantur><br />

manifeflum ,eit quod linearum T C & p C incrementa ve1<br />

decrementa kmper fmt zqualia 3 ideoque ii corporum in lock<br />

T 82: p exifientium diftinguantur motus finguIi (per Legum<br />

Coroh 2.) in binos$ quorum hi verfus centrum, five ficundum<br />

hneas T C, p C determinentur, SC alreri prioribus tranfverii fin-t,<br />

& fkcundum lineas. ripfis~ 50 C, p C perpcndiculares dire&ionem.<br />

habeant ; motus verfus. centrum, erunt szquales, & motus tranG<br />

vesfus cotyoris p erit ad. motum tranfverfum corporis T, ut motus<br />

angularis iineg- .p G, ad motum ,.angularem linear 2’ C3 idefi,,


I rq PHILC?SOPHI& NATURALIs<br />

crzpiantur dacz quanritates F, G in ea ratione ad invicem quarn<br />

ha&c angulus VCT ad angulum YCp, ut G G- FF ad FF. Et<br />

proprerca, ii cenrro C intervallo quqvis CT vcl.Cp defcribatt~r<br />

Sc&r circularis zszqualis areZ ti>ti P’PC, qw-n corpus T ternpore<br />

quovis in Orbe immobili revolvens radio ad centrum du&o defcripfit:<br />

diffcrentia virium, quibus corpus T in Orbe immobili &<br />

corpus p in Orbe mobili revolvuntur, wit ad vim centripetam, qua<br />

corpus aliquod radio ad centrum duRo Seeorem ilium, eodem tempore<br />

,~LXI defcripta fic,area Pip C uniformiter dekribere potuiffet,<br />

ur GG - F F ad FF, Namque Se&or ilk & area p Ck- @nt ad invicem<br />

ut tempora qulbus dekribunrur.<br />

Cowl. 2. Si Oi-bis YT I< EllipGs fit umbilicum habens C & Apfidem<br />

fi.lmmam ?/; eique iimilis & aqualis ponatur Ellipfis ti p k,<br />

ita ut fit kmper p C aqualis ‘IPC, & angulus YlCp fit ad angulum<br />

YC’CP in data ratione G ad F; pro alcitudine autem T C vel p&’<br />

tiribatur A, & pro Ellipfeos latere retio ponatur 2 R : ’ erit vis qua<br />

FF. RGG - RFF<br />

corpus in EllipG mobili revolvi pot& ut - AA+ ~A Cuba----<br />

8-z contra. Exponatur enirn vis qua corpus revokv?r in imm6ta<br />

Ellipfi per qunntitatem :;I & vis in Y erit Vis aL<br />

c Vuzd ”<br />

tern ~LKI corpus in Circulo ad diRantiam C Y ea “cum t’elocitate<br />

revolvi poffet quam corpus in Elljpfi rcvolvens habet in K,<br />

efi ad vim qua corpus in Ellipfi revokens urgetur iti Apii’de PY3<br />

ut dimidium lateris re&ti Ellipfeos ad Circwli iemidiametram CY,<br />

R FF<br />

adeoque valet cm: & vis qua,: fit ad hanc ut GG-FF ad<br />

.<br />

FF, valet RGG-RPF: efique hzc vis ( per,hujus Coral. I. )<br />

e VcY.4b.<br />

differentia virium in yquibus corpus P in Ellipiiimmota YPI


PRI.NCIPIA MATHEMA.TI~;A~ lLj<br />

qua corpus in IEllipG mobili 5/p k iifdcm telnporibl~s revolvi ~~ il f R<br />

p0fIk<br />

GwuZ. 3. Ad eundem modum colligetur qmd, fi Orbis immabilk<br />

.VF’K Ellipfis fit centrum habens in viriunl ccntro cj eiqUe<br />

fimik3, zquaiis sh: concentrica ponatur Ellipiis mobilis zip k j<br />

fitquc 2 .R Ellipfeos hujus lacus re&um principalc, k 2 ‘r ~acus<br />

tranfverfuum five axis major, atque at2guIus YC p fct11)7er iit ad<br />

angulum YCT ut 6 ad F; vires q”ibus corpora in Ellipfi in.<br />

122obili 8r mobili temporibus aquaIibus revolii poKunc, erunt ut<br />

FFA FFA RGC-RFF<br />

T czk5. & T c&5.+<br />

rcfpeLki ve.<br />

A et&.<br />

Coral: 4, Et univerfalieer, ii corporis aItitudo maxima CK nob<br />

minetur T, & radius curvatura quam Orbis Y‘P K h&t in J< id<br />

efi radius Circuli aqualiter curvi 9 nominetur R, & vis ccntripcts<br />

qua corpus in TrajeBo~Fq;acunque immobili YP IC revolvi po-<br />

tefi; in loco Y dicatur<br />

-----,atque TT aliis.in locis T indefinite dica-<br />

tur X, altitudine C P nominata A, & capiatur G ad F in data<br />

ratiolle anguli V”Cp ad angulum VCP: erir vis centripetLl qua<br />

corpus idem eofdem motus in eadem Traje&oria ZI p k circulariter<br />

mota temporibus iiflem peragerc Vote& ut fumma virium<br />

x + VRGGrV.RFF.<br />

A ctib;<br />

~~&. f. Data igitur :motu yorporis-in Ofbe quocunque immobili,<br />

augeri vel minui poteit ejus moeus angularis circa centrum<br />

viriun2 irt. ratione data, &. inde inveniri novi Orbes immobiles in<br />

tin&us corpora novis viri bus ten tripetis gyren tur.<br />

I- Coral. 6. Igitur ii ad rehm CV POfi&ne<br />

&tam erigatur perpelldiculum<br />

VP lollgicudinis indeterminate, jun-<br />

C’P, & ipfi aqualis agatur<br />

gaturque<br />

cp, confiituens- angulum YCp, 9$ fiS<br />

ad angulum Y’C P in data ratrone ;<br />

v.is qua corpus gyrari potcfi in Cwa<br />

ill& ,Vt k quam punQum p perpetuo<br />

rangit, *erit. reciproce ut cubus aMudinis<br />

C p, Nam corpus p, per vim inertia, nulla alia $ UrgerIte,<br />

unjformiter progredi potefbin re&a YT. Addatu! VIS y centrum<br />

:k>&JO aititudi& CT vel Cp reciproce: proport!onah &,(,per<br />

j,~ demo&rata) detorquebitur motus llle re&lrneus in’ hean<br />

curvm<br />

P II I>! u I.


12G<br />

D r, ?!lo‘I u CLlCVatn ?Q k. Efi autem IIXC CLKV~ Yp k eadem cum Curva iIl& /<br />

/<br />

,<br />

hujufmodi viribus attraQa oblique afiendere.<br />

/<br />

I<br />

pROPOSIT XLV. PROBLEMA XxX1. /<br />

~~ol~ror!u~ V$‘~i11 Coral. 3. Prop. XLI inventa, in qua ibi diximus corpora<br />

Problema iolvitur Arithmetice faciendo ut Orbis, quem corpus<br />

in Ellipfi mobili (ut in Propofitionis fuperioris Corol. 2, vel 3)<br />

revolvens defcribit in plan0 immobili, accedat ad formam Orbis<br />

cujus Apfides requiruntur, & quzrendo Apfides Orbis quem COTpus<br />

illud in plano immobili defcribir. Orbes autem eandem acquirent<br />

formam, ii v&es centripetze quibus defiribuntur, inter fk<br />

collataz, in zqualibus altitudinibus reddantur proportionales. Sit<br />

pun&urn Y Apfis fumma, 8~ firibantur T pro altitudine maxima<br />

CV, A pro altitudine quavis alia CT veI Cp, & X pro alrititudinum<br />

differentia CY- CP ; & vis qua corpus in EIIipfi<br />

circa umbilicum fiuum (7 (ut in Corollario 2. ) revolvente move-<br />

FF RGG-RFF<br />

tur, quzque in Corollario 2, erat ut AA +<br />

a id efi<br />

A wb..<br />

,ut F F A-tRG C-R F F, fhbfiituendo T - X pro A, erit ut<br />

A cub.<br />

RGG-RFF+TFF-FFX<br />

* Reducenda fimiliter eft vis alia<br />

A ca&.<br />

quzvis centripeta ad fraaionem cujus denominator fit A CL&J., &<br />

numeratores, fa&a homologorum terminorum collatione, fiatuendi<br />

fi.mt analogi. Res Exemplis patebit.<br />

‘.<br />

.Exempd. 1. Ponamus vim centripetam uniformem efi, adeoque<br />

ut t $‘, five (firibendo T - X pro A in Numeratore ) ut<br />

T C”‘* -> T T X + 3 T ITS x - x cz4bs<br />

><br />

. k collatis Numeratorurn ter-<br />

A cub.<br />

minis correfpondentibus, nimirum datis cum datis & non datis<br />

cum nondatis, fietRCG-RFF+TFFadTcfdtb, ut-FF X.ad<br />

-3TTX3-3TXX-X~~b.iiveue-FFFad-3TT+3~,X<br />

- X )I;. Jam cum Orbis ponatur Circulo quam maxime finicimus,<br />

cgeat Orbis cum Circulo j ;& ob fa&tas R, Txquales, atquc X in infinitum


zl I: hill ‘T u ut I ad 4 -82. Qare cum angulus Y C T, in defcenfti corporis<br />

cc~~4i’o~4vs1 ab Apkle i‘ummn ad Apfidem imam in Ellipfi confe&us, fi~<br />

gradllum 180; ccmficietur angulus YCp, in dekenfu corporis<br />

ab Apfidc fLlmma ad ApGdem imam, in Orbe propemodum Circulari<br />

quem corpus quodvis vi centripeta dignitati A”-3 pro-<br />

portionali dehibit , azqualis angulo graduurn !j!j j & 110; angulo<br />

repctito corpus redibit ab Apfide ima ad Apfidem fummam, &<br />

fk deinceps in infinitum. Ut ii vis centripeta fit ut diitantia cor-<br />

pork a centro, id elt,ut A fku A3 g, erit 12 requalis 4 & J n zqualis 2 ;<br />

adeoque angulus inter Apfldem fummam & Apfidem imam ZJS=<br />

qualis *gr. Ten 90 gr. Completa igitur quarta parce revolutionis<br />

unius corpus pervelliet ad Apfidem imam, Sr completa alia<br />

quarta parce ad Apfidem Eumm?m, & fit deinceps per vices in<br />

infillirum. id quad etiam ex Profiofitione x, manifefium eff. Nam<br />

corpus urgenre hat vi centripeta revolvetur in Ellipfi immobili,<br />

cLljus centrum elt in centro virium. Qod ii vis centripeta fit reci-<br />

,proce ut diitantia, id efi dire&e ut $ kus, erit n zqualis 2, ad-<br />

eoque her Apfidem filmmam ‘& imam angulus erit graduum z<br />

fieu I 27gr. I 6 tid. &~fic, & propterea corpus rali vi revolvens,, perpetua<br />

anguli hujus repetitions: , viclbus alternis ab AyGde fumma ad<br />

ham & ab ima ad hmmam perveniet in axemum. Porro fi vis<br />

centripeta fit reciproce ut laws quadrato- quadratum undecima<br />

dignitatis altitudrnis, id eit reciproce ut Ali?, adeoque dire&e ut<br />

& feu ut F-erit A-; 12 zqualis 5 ) & -J-ggn<br />

180 azqualis 3Gogr. & prop-<br />

terza corpus de Apfide rumma difcedens & fubbinde perpetuo de-<br />

:Tcellden.& perveniet ad Apfidem ham ubi complevit revolutionem<br />

i17tegram, dein perpetuo afienfu complendo aLam revolutionem in-<br />

,regratn? redibit ad Apfidem fummam : 8r fit per vices in azternum.<br />

lhcenapl. 3, Affirnenres m &a pro quibufvis indicibus dignitatum<br />

Altitudinis, & d, c pro numeris quibufvis datis, ponamus vim ‘cen-<br />

‘Am;tcAn, ideR ut binTzx”+cinT-Xa<br />

tripetam effe ut<br />

A cid.<br />

3<br />

A ctib.<br />

feu ( per ear&m Methodurn noham Serierum convergentium) ut<br />

iqy” +cT”-mbX T”“- ncXT”“+m”J;‘%XXT **’<br />

+<br />

%%+XXT”‘&.*<br />

,I_<br />

2<br />

A cub.<br />

&


PRINCIPIA MATHE~A~ICA, E 23<br />

i;r collatis numeratorurn ~erminis, fret R C7 e; _ RF F + T ]E; ]t: I,: 3 _, ?<br />

ad bT” + /I+, UC - FF ad - PB~Tm---~IIC~T-i ‘““‘*’<br />

-I- tn;-mbXT*-2 ; nryncxy-2 kc. Et hmcndo rationes u!timas<br />

quz prodeunt ubi Orbes ad formam circularem accedunt, tit<br />

GG ad dT”-I-+-CT”-‘, ut FF ad mbT”“ +TJCT” ‘, &<br />

viciffh GG ad FF ut bT”‘* + c T”*’ ad mltT”-’ + ~&CT ‘-I,<br />

QIJ~E: proportio, exponendo altitudinem maximam CV fku T Arichmetice<br />

per Unitatem, fit G G ad F F UC b + c ad vz b + n C, adeoque ut<br />

7nb-j-nc<br />

I ad ~0 Unde efi G ad F, id ell mgulus VCp ad an;uIum<br />

Vi=lcP, ut I ad d Marc’ ‘a Et propterea<br />

cum angulus P’C ‘P inter<br />

Apfidem Cunmmam & Apfidem imam in Eflipfi immobili {It 18ngr.<br />

erig angulus YCp inter eaidem Apfidcs, in Orbe quem corpus; VI<br />

bAm+cA”<br />

ten,tripeta quantitnti<br />

proportionaii dekribit , ~gua-<br />

AC&<br />

lis angulo graduum 180 4 ’ -fc • Et eodem argumel:to Ii vis tenmb<br />

+nc<br />

bArn -sAn<br />

tripeta fit Ut ---- A cab.<br />

, angulus inter Apfides invenietur gradwum<br />

r8o l/-&g= -nc. Net kcus refolvetur Problema in cafibus diffi-<br />

klidribus. Qu-antitas cui ,vis centripeta proportionalis elt, rc-<br />

&hi kmper debet in Series convergences denominarorem habentes<br />

A cab. D&n pars data numeratoris qui ex illa opcrationc<br />

provenit ad ipfius partem alteram 11011 datam, 8: pars dnta I?LPmeraroris<br />

hujus .R G G -RFF+TFF-FFX adipfiuspartem<br />

alteram non datam in cadem ratione ponendz iiint : Et quantitates<br />

fuperfluas ,delendo 3 firibendoque Unitatem pro T, obtinebitur ”<br />

pro,portio G ad F.<br />

moron, I,, l&c fi vi-s centripeta fit ut aliqua alritudinis digni-<br />

‘&T;eniri pot& dignitas illa ex mow Aplidum; & COIICKL<br />

~~&irum,fi motus totus angula+, quo corpus redit ad Apfidem<br />

;eandem,.fit ad hoturn angularem revolutionis unius, feu graduum<br />

g&,“ut numerus aliquis 13a ad numerum aIium rh & aItiwd0 nQ-<br />

--<br />

minctur, A : erit vis ut altitudinis dignitns illa ~3.~~~ 3 3 cujus h-<br />

s<br />

dex:<br />

.


&y;;; des efc 2 - 3, Id quod per Esempla fecunda manifeflum eff.<br />

undc linu:- 3 t T.T@


PRINCTPIA<br />

MATHE~~ATIcA.<br />

A%’ ml A 3, aut dire&z uc A6 vel A ‘3. DcniqLec ii corpus ~~~~~~~~~<br />

crb ApGde filmma ad Apfidem hmmam confecerit revoluclon&l in. ’ ’ *<br />

-tegmm, 8-c pwterea gradus tres, adeoque A piis il la fingulis c~rk3rr~<br />

.rsvolutionibus confecerit in confequentia gradus tres j crit VJ ad :: ~;t<br />

.963gr, ad 36~gr. five ut TZ I ad 120, adcoque Al:- 3 wit rrquslc<br />

+29 523<br />

14'?1‘4‘-i .<br />

1<br />

a<br />

& propterea ‘vis eentripeta rcciproce ut A ;%-k?* ku rcciproce<br />

uc A 2 & proxime. Decrefiit igitur vis ccntripcts in ratione<br />

paulo majore quam duplicata, fifed qute vi&us rp: propius ad<br />

duplicaram quam ad triplicatam accedit.<br />

a;!<br />

CuroZ;2, Hint etiam fi corpus, vi centri eta qw lit re+-wx<br />

u,t qu&rafum aMudinl$ 3 w~lvacur in El P ipfi umbilicum habcnte<br />

in centro virium, Sr huic vi centripetz addatur: vel aufer~ur<br />

vis alia quzwis extranea 5 cogtlofci pat& ( per Excmpla tcrtia ‘)<br />

motus Apfidum qui ex vi illa extranea oriecur : & contra. UC il.,<br />

vis, qva -corpus revolvitw in Ellipfi iit ut&, SC: vis extranea ab-<br />

lata ut .C A, adeoque V~S reliqua ut A-CA+ A Cuk, 5 erit (in Excmph<br />

+is) b aqvalis I y m zqwlis I? 1z aqualis + deoque angulus revo-<br />

Jurionis .inter Apfi,de6 zqualis .angulo graduum 1430 +’ $$* Po-<br />

‘iatiif vim il%m~&rane~m efE ‘3 5 7;~ paktibus mirlorem quam vk<br />

altera qua corpus revolvitur in Ellipfi, id e&E eG++, exifiente A.<br />

tcx-<br />

t : . *


DE MOTU tra petentiurn, & plgwis exccnrricis innitentium hit Wnfideraddlts:<br />

cu I(. 1’ 0 R 0 hI venir, Plana autem hpponiruus efk politifflma & abro’alute Iubrica<br />

ne corpora retardent. Quinimo, in his demonfirationibus, vice<br />

planorum quibus corpora incumbunt qu”eqLte tatI@.Iflt incuml<br />

bench9 uhyarnus plana his parakla j in quibus centra corporum<br />

moventur & Orbitas mavendo dei"cribunt. Et eadem kg<br />

Motus corporum in hpcrficiebus, Curves perafios fubinde determinamus.<br />

s<br />

Pujta cujuJcmpc gene& F-3 centripeta, daloqa fi ti%w Yirium cmtro<br />

turn Pluno quocuque in quo corpus revolvitur, &iJ cofmfjr<br />

Ijigzlrtirtim curdinearlam quadratwis : requz’ri ftir Motus COK<br />

pork de loco data., hata cum Yelo+tnte, jecnndwm re&%m iv<br />

~lano ilbv datam egrefl+<br />

.# I<br />

Sit S centrum,Viriwm, SC difiantia minima centri huj’us a I’lago<br />

data, T corpus de loco T fecundurn reLhtn* %‘Z egredienss &f+<br />

corpus idem in TrajeBoria fua rev6lve’ns, & TRA Tjajc&oria<br />

illa, in Piano dato defcripta, quam,i&enire oportet. Jungantur CR<br />

$2&J ‘& G in RS capiatur 3’7 proportionalis vi centripctaz c&4<br />

corpus trahicur verfus centrum $9 62 agatur VT quz fit parallela<br />

C,&(& occurrat SC in T: Vis SYrefolvetur (per Legum Corol,,z,)<br />

in vrres ST, 2-73 quarum ST trahendo corpus. fkcundum linaam<br />

piano perpendicularem, nil mueat motum ejus in hoc piano, “Vis<br />

autem altera TV, agenda fecundurn pofition&- plani, trahit car;<br />

pus dire&e verfus pun&urn C in plano datum, adeoquc facir ill’ud<br />

in hoc piano perinde moveri ac Ii vis; ST tolleretur, & corpus vi<br />

fola TYrevolveretur circa centrum & in fpatio libcro, Rata autem<br />

-vi


PRINCIPIA MATHEMATIcA?, 1’33<br />

vi centripeta 9 Y qua corpus &in fpatio libcro circa centrum<br />

LXltEIl<br />

datum C revolvitur, datur per Prop. XLII, rum TrajeQoria “PR. I’ R1 biK’S-<br />

quam corpus defcribit, cum locus gin quo corpus ad datum quod-<br />

vis tempus verfi bitur ‘J turn denique velocitas corporis in loco ill0<br />

Lip contra. ,$i$ E. I.<br />

p~o~P0sITT.0 XLVII. THEOREMA XV.<br />

POJBO god Es cenkpetd proportionalis jt dijh-hce corporis a<br />

Ct3!ltrO j corpora omnia in plank quibuJcmque revolruentia de-<br />

J&ibent f<strong>Up</strong>[es, & rmohtiones Tempokibaks qaalib@ peragent ;<br />

quque moventur in fineis re&s, ultra citroque diJ&rrendo,<br />

1 Ji~ggh eurjdi & redetindi periodh $d& Temporibw abJoL<br />

vent.<br />

NamJ fiantibus quzc<br />

in fuperiore Propofitio-<br />

Ize, vis SY qua corpus<br />

gin plan0 quovis 332X<br />

revolvens trahitur. verfis<br />

ccntrum 5 eft ut difianria<br />

A’,$?& atque,adeo<br />

ob proportionales. S Y<br />

&S&TV&C&vis<br />

2-Y qua corpus trahitur<br />

verfius pun&urn C<br />

in Orbis piano datu.mJ<br />

efi ut difiantia C.& Viyes<br />

rgitur J quibus corpora<br />

in plan0 T $&R<br />

vertintia trahuntur verfus<br />

puidhm C, fiint pro<br />

ratione diitantiarum zquales ‘viribus quibus ‘corpora undiquaque.<br />

trahuntur verrus centrum S ; & propterea corpora movebuntur iifi<br />

dem TemporibusJ in iiCdem FigurisJ*,in plan0 quovis l”RR circa<br />

pun&urn C, atque in fpatiis liberis crrca centrum S; adeoque (per’<br />

Gorol, z. Prop. XJ & Coral, 2. Prop, xxxvrrl),,Tcmporibus limper


PHILOSOPHIJ!IZ NATURALIs<br />

nF ~~~~~~~ ~~&libus~ vcl dcfcriberlt Ellipfes in plano ill0 circa centrum C,<br />

f‘lll:~S~~~l:,l 1~1 per~~dos movcndi ultra citroque in lincis re&is per ccntrum c<br />

in phno illo du2Iis, complcbunt~ #g&E* 21.<br />

His :iflincs Ctmc nfccnft~s ac deknfus corporum in iupcrficiebu’i<br />

curvis, t;omcipc Iineas curvas in plano def‘cribi, dein circa axes<br />

quofvis dacos per centrum Virium tranhntes rcvolvi, & ea revolucionc<br />

hpxficics curvas dcfcrlbere; turn corpora ita moveri ut<br />

corllm ccnrra in his fuperficiebus perpetuo reperiantur. Si carpora<br />

illa oblique akendendo (3r defccendeudo currant ultra citroque<br />

perngentur eorum motes in planis p@r axem traol%untibus, arque<br />

adeo in lineis curvis quarum revolutrone curw ilh filperficies ge..<br />

nirx tiin t. litis igitur in cafibus fufkit motum in his lineis curvis<br />

conliderare.<br />

PR~PO~ITIO XLVIII. THEOREMA XVI.<br />

rota ~lobo extri?zJecus ud angulos reaos i$j)fatp & more ro?<br />

tnrum revohendo progrediatur in ~ircdo Y~ZLW&JO j /on&&o<br />

Htz+neris cwvih-zei, pod pun@um quodvis in $0~ perimctro datmv,<br />

ex quo Globu?t2 ten& confed, ( quodpe Cyklaidem veJ<br />

Epicycloidem nomirtare licet) wit ad duplicate J;nuw wr$m<br />

arctic dimidii gtii Globum e3c eo tempore inter eundum teti@t,<br />

ut ftimma diametrorum Globi $3~ Rot& ud Jknidiametrum ~lobi,<br />

PROPOSITIO xL~x. THEOREMA xwr.<br />

Rotu Globo concave ad refZ:os dngsllos intrinlecus &$$?a~& yeruohendo<br />

progrediatur in circulo maximo j lo@tudo Itiqeris<br />

cwv&ei quod pun&~12 quodvis in Rot& perim~tro datam, ek<br />

9.~0 Ghdvm tdgit, confecit, erit ad duplicatum @urn cve&ua<br />

um~~ dimidii qui Globum toto hoc tempore hater eusdum t&-


PRIbhX?Ii4 MATHEMATICA. “3’5<br />

,Sit A,BL Globus, % cenrrum ejus, BT Y Rota ei infifien’s, E<br />

centrum RotzE, E pun&turn conta&us, & T pun&urn datum in perimetro<br />

‘Rot;~. Concipe ‘hanc ~otam pergere ih ‘&CLdO maxim0<br />

4B.L ab A per B verbs L, & inter eundum ita revohi UC ar-<br />

CLIS A& T B fibi invicem femper zquentur, atque pun&um ihd<br />

!P in perimetro Rot2 datum interea d~fcribere. Viam curvilineam<br />

AT’. Sit autem AT Via rota curvilinea d&ripta ex quo Rota<br />

Globum tetigit in A, & erit Viz hujus longitudo AT ad duplum


DE MOT u Centro item C & intervallo quovis defcribatur circulus 5vzom ,k=-<br />

C~~~~~~~l cans reQam CT in ti, Rot% perimetrum Bp in o:, ck Viam curvilineam<br />

A P in m; centroque Y 8-z intervallo Y-O defcribatur circu-<br />

Ius ficans YT prod&am .ih ga<br />

Qoniam Rota eundo femper revolvitur circa puntium conta&us<br />

B, manifefium efi quad re&a B T perpendicularis efi ad<br />

lineam illam curvam A P quam Rotas puntium P defcribit, atqut<br />

adeo quod re&a 17’ tanget hanc cgrvam in pun&o T, Circuli<br />

rc om radius fenfim au&us vel diminutus aquetur tandem difiantigz<br />

CP 5 &, ob fimilitudinem Figur3z evanekentis Pn omaq & Figura<br />

2” .FE;G VI, ratio ultima lineolarum evanefcentium P m, P s3 T 03 *P q4<br />

id


HEEATIECA*<br />

14Y<br />

id ~;fi, uni momefltancarum curv32 AP, rcQ3z L. i n r: R<br />

CT, arcus circularis BT, ac re&az k*‘P, eadem erit qw linea- Pnlht~i 5a<br />

rum ‘P VP T F9 T G, T 1 refpehive. Cum autem YF ad CF &<br />

Y,H ad C Y perpendiculares funt, anguliquc MVG, VCF prop-,<br />

terea aequales j & angulus YHG (ob angulos quadrilateri HVE ‘P<br />

’ ad ,V & T re&os) hgulo CET aqualis eit, fimih erurlt triangula<br />

VHG, CE P 5 & inde fret ut E P ad C E ica HG ad k;lrii<br />

fiu HP & ita ICPad KP, Sr compofite vel divifim ut CB ad<br />

CE ita P I ad P IL, &I duplicatis confequentibus ut CB ad 2 &’ E<br />

ita T I ad T Y; atque ita adeo T 2 ad T FW, Efi igitur decrementurn<br />

line= VT, id cfi, incrementum hex: 13 Y- .V‘T ad incremen-,<br />

turn linez curve A T in dsta ratione C B ad 2 CE, & propterea<br />

(per Coral. Lem. IV.) longitudines i3 Z;r-- VT 6~ AF’, incrementis<br />

illis genitx, lint in eadem ratione. Sed, exifiente B Vradio,<br />

efi YT co-finus anguli B Y‘T ku $ B E T, adeoqcreB V-P?P<br />

finus verfus ejufdem an uli j 8z propterea in lrac Rota; cySus radius<br />

efi $ BY, erit BY- 9 I, duplus finus verfk arcus i BT. Ergs<br />

AT eit: ad duplum finurn veriilm arcus $ B T er t a CE ad C B..<br />

earn autem AT in Propofitione priore Cycloidem exrra<br />

Globurn, alteram in pofieriorc Cycloidem intra Globum diRinQi-,<br />

onis gratis nomiizabimus,<br />

C’MOL I. Hint fi defcribatur Cyclois integra ASL & bifecetur<br />

lea in S, wit Iongitudo partis T S ad longitudinetn V T (quz duplus<br />

efi finus anguli YB T, exifiente E B radio) ut z CE’ ad C BP<br />

atqwe adeo ill ratione data. -.<br />

CwoL 2. Et longitudo femiperimetri Cycloidis 1$ S zquabitur<br />

linex re&x quaz efk ad ROW diamerrum B Y, ut z C .E ad CB,<br />

Facere aut Coypus penduluna ofcilebtir in Cycloide data.<br />

htra Globwm RV’S, centro C defcriptum, detur Cyclois gR$<br />

‘-bife&a in 2’3 & pun&is fuis extremis g&t S fiuperficiei Clobi hint<br />

inde occurrens. Agatur CR bifecans arcum &$S in 0, & produca-<br />

‘%ur ea ad A, ut fit c A ad ‘CO ut CO ad C X. Centro C ‘in-<br />

T<br />

servallQ


te&allo CA dekribatur Globus exterior ,!fB 2), & intro hunt 6k&<br />

bum a Rota, cujus diameter fit AO, defkibantur OWE Semicycloides<br />

A$, AS, quz Globum interiorem ta,ngant in g& 8 & Glob0 exteriori<br />

occurrant in A. A pun&o illo A, Fib A P T IongitudinenE<br />

A R Equante, pendeat corpus 27, & ita intra Semicycloides A&<br />

AS ofcilletur, ut quoties pendulum digreditur a perpendicul,o AR,<br />

Filum parte hi fuperiore AT applicetu? ad Semicycloi&em illam<br />

ATS verfus quam peragicur mows, & circum earn ceu obflwUlum<br />

fle&cur, parteque reliqua TT cwi Scmicyclois nondum objicitur,<br />

protendatur in lineam re&am; & pondus 1 ofcillabitur in<br />

Gycloide data, R S, 4 22.. F.<br />

hyrracenim % ihm T T turn Cycloidi XRS in T, turn circulo<br />

205 10 K agaturqueC& & ad Fili partem retiam F T e pun&is<br />

extremisF ac I, erigantur perpendicula TV3, TW, occu;renth re-<br />

&x Grin B 8-2 kK Patet, ex co&-u&one & genefi fimjlium. Figurarum<br />

As, s& per endicula illa P B, TWabkindere de C Y h-<br />

gitudines YB, Y?T lt. otarum diamctris 0 A, 0 .&2 xquales. &,fi igitur<br />

2T ad PIP (duplum hum angull YB P exillterl re + B Y- ra-<br />

dio)


IN PIA MATHEM&<br />

939<br />

die) tit B FTad 23 ZiT; feu A 0 + 0 W ad AO, id efi (cum fint Cd<br />

L ! 1: I L<br />

ad CO, CO ad CR & -divifim AQ ad 0 R proportionales,) ut ~xr!,ltl-.<br />

CA-j-CO ad CA velj ii bifecetur B Y in E, ut 2 CE ad CB.<br />

Proinde, per Coral. I. Prop. XLIX, fan itudo partis re&z Fili FPT<br />

zquatur kmper Cycloidis arcui‘p & & k ilnm totum A*5? T aquatur<br />

limper Cyeloichs arcui dimidio A‘;P S, hoc eit (per Corol, 2. Prop.<br />

XL rx) longrtudml AR. Et propterea vicifflm ii Filum manet Ternper<br />

azquale longkudini .A .R movebitur pun&urn T in Cycloidc<br />

data L&Rs. & E, FL?.<br />

Coral. Filum A-82 aquatur Semicycloidi AS’, adeoque ad


1p3 ~~~LosoPE-II~ NA<br />

,b, ! 5 r ,, _ d:L” & acceleratiolles fubfequentes, his partibus proportionales, funt<br />

; I- :: cti,lill ut tcmi & tic deinceps. Sunc igitur acceleracio~es atque<br />

a,&o vc]ocitates genitz & partes his velocicaeibus defcrcnpt,z parr&.::~<br />

defiribcrld~, femper ut totz; 8c propeerea pllrtC5 ddbri~~~i~<br />

&;; datam &-vantes rationem ad invicem iitnlal evanefcen-t, id efi,<br />

~~~~~~~~ duo c?d‘cillantia Gmul pervenient ad perpendiculum AR.<br />

~~~~>;quc pi&m afccnfus perpeildiculorum de 10~0 irlfimo R, per<br />

co&m arcus Cycloidales mow retrogrado Fzacrf-i9 retnrdentur in<br />

l~cis hgulis a wribus iifdcm a quibus dekenfus acceI<br />

7 rabantur,<br />

p.itcC vclocitc!,te s akenfuum ac deficnfuum per eo17dtm arcus fa-<br />

&rum squales efl”e, atque adeo temporibus zqualibus fierij or:<br />

proptereag cum Cycloidis partes duze AS & K *ad utrumque perp:diculi<br />

latus jacentcs ht Gmiles & axpales, pendwfa duo olrcil-<br />

2~cioncs fhs rrlnl totas quam dimidias iii&m temporihs hnper<br />

peragent. g 1;:. ‘D.<br />

“i<br />

CbrOL %:is qua corpus T in 12: quovis T acceIeratur veI retartur<br />

in Cpcloide 3 efi ad totum corporis ejurdem Pondus iu loco<br />

akif’ho S vel L& ut Cycloidis arcus TR ad ejulilem arcum J’.,R<br />

rcl RR,<br />

~ROPOSITIO LII. PROBLEMA XXXIV.<br />

Centro quovis G, intervallo GH Cycloidis arcurn W S zqaalltes<br />

defcribe kmicirculum HR M% fkmidiamctro G K bife&um.<br />

EC<br />

fi vis centripeta, difiantiis Iocorum a centro proportionalis tendac<br />

ad cenrrum G, fitque ca in perimetro Ndb;. Equalis vi centripesz<br />

in perimetro Globi 20 S (J%fe Fig, Prop. I,.) ad iphs dentwm<br />

tendend; ck eodem tempore quo pendulum F dimitritur e<br />

loco hpremo 5’, cadat corpus aI.iquod L ab M ad G: quoniarm<br />

vires quibus corpora urgentur hunt zquales fiib initio & fpaciis<br />

dcfcribendis TR, LG f emper proporrionales, arque adeo, -ii x-<br />

qumu TR & L G9 aquales in locis T & L j : patct corpora illa<br />

dekribere fpatia ST, HL aequaIia fu b initio, adeoquc &bin& pergcre<br />

EquaIiter urgeri, & xqualia fpatia dekiibere. @arc3 per Prop.<br />

XXXvIIh Empus quo corpus. defcribit arcum $FT’ efi ad tempus<br />

okil-


~oru Globi inverf& & fubduplicata ratione Vis abfolutz Globi etiam<br />

CoR"o""si~inverk 8 E, 1.<br />

moron, 1. Wine etiam Ofcillantium, Cadentium & Revolventium<br />

:corporum tcmpora poffunt inter fe conferri. Nam G Rotz, qua CYclois<br />

intrn globum defcribitur, diameter confiituattir aequalis fern&.<br />

diametro globi, Cyclois evadet Linea re&a per centrum globi tranfiens,<br />

& Okillatio jam erit dekenfus & fubkquens ai‘cenfils in hat<br />

refita. Unde darur turn tempus defcenfus de loco quovis ad<br />

zcntrum, turn tempus huic zequale quo corpus uniformiter circa<br />

centrum globi ad difianciam quamvis revoivendo arcum quadrantalem<br />

dekribit. Efi enim hoc eempus (per Cafum fecundum<br />

) ad tempus kmiokillationis in Cycloide quavis 2$.J S ut<br />

I ad 42$.<br />

Cord. 2. Hint etiam ,conceeQantur qua2 ?FFennecs & Hz4genius de<br />

Cycloide vulgari adinvenerunt. Nam fi Globi diameter augeatuk<br />

in infinitum : mutabitur ejus fuperficies fpharica in planum, Vifque<br />

centripeta aget uniformiter kcundum lineas huic piano perpendiculares,<br />

& Cyclois noitra abibit in Cycloidem vulgi. Ifio autem.<br />

in cafu longitudo arcus Cycloidis, inter planum illud & pun&urn<br />

defcribens, aqualis evadet quadruplicato finui verfo dimidri arcus<br />

Rotg’inter idem planum & pun&urn defcribens 5 ut invenit menno:<br />

Et Pendulum inter duas ejufiodi Cycloides in fmlili & a+<br />

quali Cycloide temporibus aqualibus Ofcillabitur, ut demonfiravit<br />

.&genius. Sed & DefcenCus gravium, tempore Ofcillationis unius,<br />

is erit quem Htig~nizts indicavit,<br />

Aptantur. autem Propoiitiones a nobis dcmonfiratx ad veram<br />

confiiturionem Terra, quatenus Rota eundo in ejus circulis maximis<br />

defcribunt motu Clavorum, perimetris fuis infixorum, Cycloides<br />

extra globum j & Pcndula inferius in fodinis & cavernis Terra<br />

Eufpcnfa, in Cycloidibus intra globes CWcillari debent, ut CXi’cilIationes<br />

amnes evadant Iiochrona., Nam Gravitas ( ut in Libro<br />

tertio docebitur) decrekt in progrefi a fuperficie Terra, fir+<br />

film quidem in duplicata ratione difiantiarum a centro ejus, deorfim<br />

vero in ratione fimplici,<br />

. .<br />

PROPO-.


~ofg-efis FipWum cwvilinearum. qivadra&hris, inwenire V&es quibus<br />

corpora if2 da& cuPvis lineis OJciLlationes Jemper .lJocbraw5<br />

peragent.<br />

Qfcilletur corpses, ?@ in curva quavis linea STR & cujus axis fit.<br />

Q R tranf’iens per virium centrum 6. Agatur TX quz curvam il.-<br />

lam in corporis loco quovis T contingat, inque hat tangents T.&T<br />

- capiatur TTazqualis arcui TR. Narn, lOngi tudo arcus illius ex Fi--<br />

gurarum quadraturis (per M&ados vulgares) innotefcit. De punA<br />

&b IT’ educatur re&a 2-2 tangent,i perpendicularis. Agatur CT per;<br />

pendiculari illi occurrens in 2, & crit Vis centripeta proportionalis<br />

reti%x TZ. Li& E, L<br />

Nam:


x.46, p~-moS’oPH~~ ATWRALIS<br />

~~~~~ fi vis, yua corpus tralkw de T.verfus G exponrfur per<br />

1) E -idO T I ’<br />

b, 0 F. ? 0 !i C : i rcfcsam TX capcam ipfi proportionalem *refilvetur hx In vires<br />

y-y, 1-2 j q1larum 7~ trahendo corpus fecundurn longitudii~em<br />

Fi]i ‘P’T, motutn ejus nil mUtar, vis autem &era TT motum ejus<br />

ill ,ctlrva J’T’Rgdire&e accelcrat vel direct retardat. Proinde<br />

C1lm llGrc fit 11~ via defcribenda TR, acceleratimes corporis vel refardariollcs<br />

in Q[cillationum duarum (majoris Sr minoris) parti-<br />

~~~~s proporcionalibus defcribendk erunt krnper ut partes ilIz &<br />

propterea facienl: ut partes illa fimul d&ribamur. corpora autem<br />

QuLc partes totis icmper proportionales fimul defcribunt, hnul defhxnc.<br />

tocas. & E. 2).<br />

C~TO~. 1, Hint ii corpus 7 Filo re&ilineo AT a cenrro A pendens,<br />

defcribat arcum circularem STR& Ik hterea urgeatur fe-.<br />

CLmdim lineas parallelas deorfiun a vi aliqua,<br />

~UX fit ad vim uni-<br />

formem Gravicatis, UC arcus TR ad ejus finurn TN: xqualia em<br />

runt Ofcillationuttl fingularum rempora. E tenim ob parallelas<br />

TZ, A’]


ATHEMA ,l! 45<br />

partium illarum aliqua. centro C, intervallis CD, Cd dekriban- ~~~ I:II<br />

tur circuli 59 Z iGdt3 line32 curviz STt R occurrentes in T & t. Er P RIRLwS.<br />

ex data tuna lege vis centripetx, turn<br />

tiltitudine CS de qua corpus cecidit j<br />

dabitur velocitas corporis in alia quavis<br />

altitudine CT, per Prop. XXXIX.<br />

Tempus autem 3, quo corpu,s defkribit<br />

lineglam Tt, ek ut lineok hujus longitudo<br />

(id eit ut fecans anguli t TC)<br />

dire&e, & velocitas inverk. Tempori<br />

lfiuic proportionalis fit ordinatim applicata<br />

59 N ad re&am CS per pun&urn<br />

2) perpendicularis, Sz ob datam D d<br />

erit re&angulum 2) d XD 2\LT hoc et3<br />

area I) Nn d, eidem tempori pr’opor+<br />

tionale, Ergo G S N 12 fit curva illa linea<br />

quam pun&urn N perpetuo tangit,<br />

,erit area S ND S proportionalis tempori<br />

quo corpus defcendendo def’crip+<br />

fit lineam $2”; proindeque ex inventa illa drea dabitur Tempus.<br />

L& El I.<br />

PROPOSITIO<br />

*<br />

LV. ,TWEOREMA’XIX.<br />

si; coypps +ovetur iri Jiijyjcie quatun+que cukva, S,c@s’axis pel”<br />

+centrum Virium tra@, & a corpore in axetn dhttatw Peri<br />

pendicularis, eique pmalleh & squulis ab sxis pm&o qtioruis<br />

&to dmdtur : dice quad parullela ila aream temporiproportio-<br />

Salem deJcribet. .’ * ,/ :<br />

Sit BSKL fuperficies’curva; 'ii, toi-lj,,, & ea Geudlvenk,’ SPt I?<br />

Trajefioria quam corpus in :eadem’ d&&ti~~ S’iriititik TrajeBoriaze,<br />

0 MNK axis ruperticiei curvaz, TN reRa a ,cprpgre in axem<br />

perpendicularis, 0 P huic patallela & aeqkilis, a pun&o 0 quad in<br />

axe datur edu&a,, A59 yefii ipq ,Traje$,oria: a ~~un&o T in line%<br />

yolubilis 0 T plan0 A0 T 6: ,efcnpttim, A vkfiiglt ikitium ptin&o S<br />

refpondens, 7 C re&a a corpore ad, kentrum du&a j 2-G pars ejus<br />

9i centGpet8’ qua corpus urgetur in centrum C proporcionalis;<br />

$f”iIf re&a ad fuperficiem curvam perpendicularis, TI pars ejus vi<br />

prefionis, . qua corpus,urget lilperf$ein vicifimguewgetu~r, verfis .M<br />

a


w<br />

PHILOS~~XE NATWRAEIS<br />

a filperficie, proportiona-<br />

Y) E id0 T U<br />

COR~ORU~~ lis j fPHTF<br />

re&a axi<br />

parallela per corpus tranfiens,<br />

& G F, I l+l relh 73<br />

;1 pun&is G SE I in pa-<br />

raIleIam illam T H TF<br />

perpendicularitcr den&<br />

CT. Die0 jam quad area<br />

AtI 33, radio 0 T ab initie<br />

mows defiripta, fit<br />

zempori proportionalis,<br />

Nam vis TG (per Legum<br />

Coral: 2,) refolvicur<br />

ifri vires TF, FG; & vis<br />

T.l in vires T H, H I:<br />

Vires autem TF, T H<br />

agendo fecundw lineam<br />

T F piano AOT’ perpendicularem<br />

mu tan t Co-<br />

Iummodo motum corporis<br />

quatenus huic plano perpendicularem. Ideoque motus ej.w<br />

quatenus kcundum pofitionem plani fa&us, hoc eit, mows pun--<br />

Et-i T quo Trajefloriz vefiigium A T in hoc plano defc&<br />

bitur, idem. efi ac fi vires TF, TH tollerentur, & corpus CoIis vi?<br />

ribus FG, HI agitaretur ; hoc efi, idem ac ii corpus in piano<br />

AO T, vi centripeta ad centruin 0 tendente Sr fuuiYlmam viriam<br />

FG & HI aquagte, dekriberet curvam AT. Sed vi tali dcti.ribicur<br />

area A0 P (per Prop. x.1 temp,ori proportionalis. 82% D;<br />

’ Coral. Eqdem argumento fi corpus a viribus agitaturn ad centra<br />

duo vel plura in eadem quavis reQa CO data tendentibus, def.riberet<br />

.in [patio libero lineam quamcunque curvam ST; foret area<br />

A 0 • SF tempori femper prbp&tionalis.<br />

PROPOSITIO LVf. PROBLEMA XXX$IIe<br />

ConceJs Figurarm cwv&euruw qzdra~tiris, ddj$xe ittim lege<br />

F% centripetLe d centrurn datum tend&&s, turn luperficic curwu<br />

cu+iz axis per centrum iUtid ~.runJir: j iwueniend~ e.@ TV&?,<br />

i’fOri& quam corps in eadem~tiperficie defmibet, de loco data, ddfd<br />

mm Yelocitate, we&is plagm i# JiperJicie iMa ddgam egrej%m.<br />

Stanti-


RINCIPZ:A MATHEhUiTrc~.<br />

IAt.7<br />

Stan ti bus qua: in fuperiore Propofirione canitrutia funt , cxeat :,?; f. k<br />

corpus de loco s in Trajeeoriam inveniendam J’Tt A i &, ex da- P 7, 1 &I :’ a<br />

ta eju, velocitate in altitudine SC, dabitur ejus velocitas in alia<br />

‘quavis alticudine 2°C. Ea cum velocitate, dato tcmpore quatll<br />

inimo, defcribat corpus TrajeQoriaz fia: particulam firt, firquc<br />

3 p vrtfiigium ejus in plan0 A0 T defcriptum, Jungacur Op, KC<br />

CirFe!li centro 2: interyallo Tt in iirperficie curva defcripti fit Fp R<br />

vefiiglum Elliptlcum in eodem plano 0 A?‘P~ defcriptum, Et ob<br />

datum magnitudine & potitione Circellum, dabitur Ellipfis illa<br />

5?p & Cumque area T Op fit tempori proportionalis, atque adeo<br />

ex dato tempore detur, dabitur Op pofitione, & inde dabitur<br />

communis ejus & Ellipfeos interkQio p, una cum angulo OT’p,<br />

in quo Traje&orize vefiigium ATp fecat lineam 0 ‘P. Inde augem<br />

invenietur Traje&oria: vefiigium illud ATp, eadem mcthodo<br />

qua curva linea .YIKk, in Propofitione XLI, ex fimilibus dark<br />

inventa fuit. Turn ex hngulis vefiigii pun&is T erigendo ad pknum<br />

A 0 fp perpendicula T T fuperficiei curve occurrentia in r”s<br />

daburatur fingula Traje&ork pun&a T. ,$& E. I;<br />

Ha&enus expofui Motus corporum attraQorum ad centrum Immobile,<br />

quale tamen vix extat in rerum natura. Attratiiones enim<br />

Geri Sblent ad corpora; & corporum trahentium & attra&orum<br />

z&ones femper mutuz funt & azquales, per Legem terkn: ad-<br />

-eo .ut neque attrahens pofit quiekere neque attraQum, fi duo fint<br />

c’orpora, fed ambo (per Legum Corollarium quartum) quail atprafiione<br />

mutua, circam gravitatis centrum commune revokantur :<br />

& fi plura fint corpora (quze vel ab unico attrahantur vel omnia<br />

fe m~rw attrahant) hat ira inter fe moveri debeant, 111: gravitatis<br />

centrun commune vel quiefiat vel uniformiter moveatur in direc-<br />

8um. @a de cauCa jam pergo Motum exponere corporurn fe mu-<br />

.ouo tr-hentium, confiderando Vires centripetas tanquam ActraAiones,<br />

qua&s fortaffe, ii phyf$e loquamur, verius dicantur !mpulfis.<br />

In Mathematicis enlm Jam verfimur, & propterea I@S<br />

difpurationibus Phykis 3 familiari utimur ferrnone$ quo pafkWIff<br />

.a Le&oribus &4athematic:is, facilius intelligi.<br />

u2<br />

PRQ-


I’Ixvolv:w tur curpora 8, T circa commune gravitatis centrum<br />

cd’., pqxdo de S ad T deque T’ ad J& A data pun&o’s @is.


L.<br />

E’RRNC~~P A MATHEMATICS. 143<br />

.~efkribit, eric fimilis SC xqualis Gurvis quas corpora J, p defcri., I,~;~ T ;I.<br />

bunt circunm fe mutuo: proindcque (per Thc~ur. xx) fimiI;s Curvis PIJ lx’ J.<br />

ST & TgY, quas cade m corpora defiribmlt circum comn~une<br />

gravitatis ccntrum C: id adeo quin proportioncs ]irlcarum SC’, c ;J<br />

& ST vel sp ad inviceul danrur.<br />

Gzs. I. Commune ikd gravitatis centrum C, per Lcgum Corollarium<br />

quartum > Vel quiefcit vel inovetur uniformiter in directurn,<br />

Ponamus primo quad id quiefcit, inque s &p loccnrur car-.<br />

pora duo, immobile iI s , mobile in p, corporibus S & ;P fimilia<br />

& aquah Dein tangant re&z “33 R 8-z p P Curvas Pg& p 4 ill<br />

fp &p, &, producantur CR&: ~4 ad R SC r. Et, ob fimil,tudio<br />

nem Figurarum &T I? $& sp Y q3 erit R .$$,ad Y y UC CP ad sp, adeoque<br />

in data racione. Proinde ii vis qua corpus L;” veri’us carpus<br />

S, arque adeo veriils centrum incermedium C attrahitur, c&x<br />

ad vim qua corpus p verfus centrum s attrahitur in eadem illa ra-<br />

Gone data ; h3e vires xqualibus temporibus attraherent femper corpora<br />

de tangentibus P R, p I ad arcus F’&p 4, per intervalla ipfis<br />

proportionalia R LQ Y 4 ; adeoque vis pofierior efficerct ut corpus<br />

p gyraretur in Curvap 4 v, qua2 iimilis effet Curve YLQ< in qua<br />

vis prior efficit ut corpus T gyrerur, & revo!utiones ill‘dern cemporibus<br />

complerentur. At quoniam vires ill,?: non funt ad invicem<br />

in ratione CP ad sp, kd (ob Gmilitudinem & zequalitatem<br />

corp,orum S & s,, 2’ & p, &, zqualitatem difiantiarum ST, sp]<br />

iibi mutuo 22quales; corpora aqualibus temporibus xqualiter tra-<br />

&ntur di: tangentibus : 6% propterea, wcorpus poiterius p trafratur<br />

-per, intervalium majus y q, requiritur tempus majus, idque in dilb-<br />

&plicata ratione intervallorum j propterca quad (per Lemma decimum)<br />

fpatia, ipfo rnotus initio defcripta, filnt in duplica~a ratione<br />

temporum, Ponatur igitur velocitas corporis p efk ad veIocitatern<br />

corporis T in fubduplicata ratione difiantix sp ad difiantiam<br />

CP, eo ut temporibus quz fint in eadem i‘ubduplicara ratione de-<br />

@rihantur arcus p 4, $P & qui Cunt in ratione incegra: Etbcorpora<br />

p, p viribus zqualibus fempcr attratia defcribent circum centra,<br />

quiefcentia C & s Figuras fimlles T $QK p 2 ~1, quarum polkrior~<br />

fimilis efi & xqualis Figur3z quam corpus P circum corpusp<br />

l?zq*<br />

mobile S defcribit. L&E. 22:<br />

C&S. 2., Ponamus jam quad commune gravitatis centrum, U.IGI.<br />

cum {patio ,in quo corpora moventur inter fe, progredicur uniformiter<br />

in direQum; &, per Legum Corollarium kxturn2 m0tUS<br />

omnes-in hoc Qatio peragensur ut prius, ackoque corpora defcribeng


PHI‘EOSO'PHIAE NATURALIs<br />

IjC<br />

D F. M 0-r u bent circum k mutuo Figuras eafdem ac prius,& propterea<br />

C~~~~ORUM ~4 21 fimiles & aquales. SE. D.<br />

Fjgura<br />

Care/. I. Hint corpora duo Viribus difiantiaz fke proportionalibus<br />

fi mutuo trahentia, dekribunt (per Prop. x,) & circum cornmum<br />

graviratis centrum, & circum k Itlutuo, Ellipfes concentricas:<br />

& vice verfa, Tr tales FigwE defkibuntur, ii;lnt Vires difiantia<br />

proportionales.<br />

Co&, z. Et corpcra duo Viribus quadrato diftantia fi’az recipro..<br />

ce proportionalibus dekibunt (per Prop. XI, XII, XIII) & &cum<br />

commune gravitatis centrum, & circum fi mutuo, SeQiones conicas<br />

urn bilicum habentes in ten tro circum quod Figurne defcribuntur. Et<br />

vice verfi, di tales Figure defcribuntur, Vires centripetx funt quadraro<br />

diltantk reciproce proportionales.<br />

Cord. 3, Corpora duo quavis circum gravitatis centrwm corn--<br />

mune ggrantia, radii5 & ad centrum illud & ad k mutuo &&is,<br />

defcri bun t areas temporibws proportionales.<br />

PROPOSITIO LXX. THEOREMA XXII.<br />

Corporum dztorum S &J P circa commune graruitatis centrm C<br />

uewohentimz Temptis period&n tJe ad Temptis periodicund carporis<br />

a?tmtrius I?, circa uherum immotum S~gywnth & Fig+<br />

.ris qud corpora circum fe ~KWO defcribunt Figtiram/imilcm &<br />

eqtialem deJcribentis, in fubduplicata ratione corporis alter&m S,<br />

.adJ’zmmam corporum S -t- I?.<br />

Namque, ex demonftratione fiperioris Propofitionis, tempora<br />

,quibus arcus quivis dimiles T 2 & pq defcribuntur, fknt in fibduplicata<br />

ratione diitantiarum CT Sr SI) vel sp, hoc efi, in $ubduphcata<br />

ratione corporis Sad fummam corporum S+ T. Et componendo,<br />

fumma temporum quibus arcus omnes fimiles T $j & p LJ<br />

defcribuntur, hoc ef& tempera tota quibus Figurat: tot= fimiles dekribuntur,<br />

Cum in eadem fubduplicata ratione. $& E. ‘22.<br />

PRO-


PIi,OPOSlTIO LX. THEOREhlA SSiII.<br />

Nam.fi defcrcriptz Ellipfes efint fibi invicem squa.IesJ tcmpora<br />

period& (per Theorema Cuperius) forent in f&~duplicata ratl~~~<br />

corporis S ad fimwnam corporum S +T. hlinuatur in hat rati<br />

ternpus periodicurn in EllipG pofkeriorc, & rempora periodica cvadent<br />

xqualia; Ellipkos autem axis principalis (per Prop. xv.] m:nueeur<br />

in ratione cujus lzsc elt Mquiplicata, id efi in ratione, CU”~:~S<br />

ratio S ad S + T efi triplicata j adeoque erit ad axem principkn<br />

Ellipfeos alterius , ut prima duarum medie proportionalium inter<br />

s+P & Sad S-0’. Et imveri‘e, axis principalis Ellipkos circa<br />

corpus,‘mobile &f&ripLz erit ad axem principalem dct’cripcz ci~cw~<br />

inlmobile, ut &+cp ad primam duatum mcdie proporcisnakm b?;-<br />

ter &Q-P &S. 2p.D.<br />

PROPOSITZO EXI. THEOREhl,t^i XXIV.<br />

Nam vires illa, quibus corpora fe mutuo trahunt, t~~~~~d~<br />

,ad corpora ) tendunt ad com,mune graviratis centrum ~nteymc-<br />

*dnm 3


12~: bh 1’ Cl dium ) nclcoque ezcwdem firnt ac ii a corporc intcrmcdio lllalzaw<br />

r:,na P ox Ll !‘I Jyellt* & E. cD.<br />

Et: quonian~ data cit. ratio difiantix corporis utriufvis a WIltTo<br />

ill0 communi ad dil]rantiam corporis cjufdcm a corporc altcro, da*<br />

bitLIr rario cujufvis potchris difhnth unius ad tandem pot~fiatcm<br />

dithnti;c altcrius; ut & ratio quantitatis cujufiris, qu32 cx una<br />

difi;lntin $L quantitatibus datis utcunque dcrivatur, ad quantitatem<br />

aliatu, qux ex alrcra diflantia & quantitatibus totidcm datis datamque<br />

illam diiktr~tiarum rationem ad priorcs habcntibus fhiliter<br />

derivatur. Froinde,fi vis, qua corpus umm ab altcro trahitur, fit<br />

dire& vcl invcrfe ut dilt-ancia corporum ab inviccm j VC~ ut CJWG<br />

libct hujus ditkwtin: pot&s; WI denique UC qwltitns qu;t”v~s ex<br />

hat difiantia &z’quantitatibus datis quomodocunque dcrivara : wit<br />

cadem vis, qw corpus idem ad ~onm~~~~~e graviratls cmtrum trahicur,<br />

dir&c jridcm vcl invcrfc ut corporis attra&i dihrrtia a cc&<br />

~ro illo communi, vel ut eadem dikmtiz hujus pot&as, vcX dcnique<br />

UC quanticas cx 1x1~ difiantia & analogis quantitatibus daris’hiliter<br />

dcrivata, Hoc efi, Vis trahentis eadcm crit l;ex ref’e-<br />

&u difinxke utriufquc. &E. D,


PRINCIPIA MATHEM~ucA.<br />

Jj3<br />

EX datis corporum motibus fib initio, datur uniformis motlls t,i;; ;,‘t<br />

oentri communis gravitatis ) it & 1Ilotlls fpatii quad una cum hoc i’aC’ ‘.f:”<br />

centro movetur uniformiter in dire&urn, net non corporunl rile.<br />

t-US initiales refpeQu hujus fpatii. &lotus autem fiibkquentes<br />

(per Legum Corollarium quinturn, & Theorema noviflimum)<br />

perinde fiunt in hoc fpatio, ac ii fpatium ipfum una cum cornmuni<br />

ill0 gravitatis centro’ quiefceret3 & corpora non traherenc $2<br />

mutuo, fkd a corpore tertio Vito in centro illo traherentur. Corporis<br />

igitur alterutrius in hoc fpatio mobili, de loco data, fecundum<br />

datam re&am, data cum velocitate exeuntis, k vi centripeta<br />

ad centrum illud tendente correpti, determinandus efi motus per<br />

Problema nonum & vicefimum fextum: & habebitur limul mutus<br />

corporis alterius e regione. Cum hoc mote componendus<br />

efi uniformis ille Syfiematis fpatii & corporum in eo gyranrium<br />

motus progreGvus fupra inventus , & habebitur mows abiblutus<br />

corporum in fpatio immobili J& E, 2.<br />

PROPOSITIO LXlV. PROBLEMA XL,<br />

Ponantur prim0 corpora duo T& L commune habenria gravitatis<br />

ten trum 9, Dekribent hzc (per Corollarium primum ‘I’heo~<br />

rematis XXI) Ellipfes centra habenres in 23, quarum magnitudo ex<br />

Problemate’v, innotefcit.<br />

Trahat jam corpus tertium<br />

S priora duo T & L viribus<br />

acceleratricibus ST., SL,<br />

& ab ipGs vicifim trahatur.<br />

‘Yis ST (per Legum Cor. 2 .)<br />

refolvitur in vires SCD, ‘D Tj<br />

8r vis S-i; in vires SD, D L.<br />

Yires autem 2) T, 2> L, qua:<br />

lrunt ut ipfarum kimma TL,<br />

acq ue adeo ‘ut vires accelerat&es<br />

quibus corpora I & L k mutuo trahunt, addire *his vi&<br />

bus corporum T & ~5, prior priori & pofierior pofleriori, corn--<br />

ponunt vires diitantiis I) T ac 5!J L proportionales,<br />

X<br />

ut prius, fed<br />

viribus


Ifi4 PHILOSc)P%4XB NATURALIS<br />

I-) E ~0 T IJ viribus prioribus majores 5 adeoquc (per CoroI. I. Prop. x. & ~orol,<br />

I 8r 8. Prop. I V) eft-iciunt ut corpora illa defkribant EtlipfGs ut prizts,<br />

fed motu celeriore. Vires reiiqux acceleratrices STI & $53, a&iojnibus<br />

kmtricibus SB X T & Sz> X L, qux runt ut corpora ) trah~do<br />

corpora illa zquditer 8~ ficundum lineas ~1, L+. K, ipfi 2, J’<br />

paraileias, nil mutant iitus ebrum ad invic~n, fed faciwxt ut Jpfi<br />

zqual-itet .accedant ad linean PK; qwrn du~fiam 3concipe per medium<br />

corporis 3, & Iinez z)S pe~pcnd.icula~wn. hp&eQl.r ax&<br />

zem ifie ad lineam JKacceffus fa&ndo ut Sykema corporCum T & L<br />

CX Lllla yarre, & CorplS S ex PItbra, jufkis cum vdoci~~atibus, gytzentur<br />

circa commirnc :gravicatis cen’tr.tim 6. Tab mctu cer;pus 8<br />

(eo quad fumma %ium kr%otricium $‘m x T & $9 K ,L, d$fiau-<br />

X;ia C S ~proporcionalium ) tendit verfus centrmn .C) ~d&&4.Gt El-<br />

~ORI’ORUI\I<br />

lip&2 circa idem c; & ptit~&rrm D, & ,proportion&s C$, :C$?&<br />

d&dbet l31~~ip$i~1 ~co-nk&dem e Fegimc, -Gorpora plltem ‘r & fi<br />

viribus motricibus SC9 x 37 ~~.............................,.......,..,,.,.............. .,... ok<br />

2% $9 XL, (prius priore, 1<br />

pofierius $o.fiepioEe] &Qu~~ $@-‘us,v - ” --<br />

liter & fecundum lineas pa- .;<br />

raJ.l&& -rf & .h .J{ :cat .dic- i<br />

\ B<br />

rum eR ) attratia, pergent<br />

\<br />

( per Le&uih Corollarium Kimw ,.. i<br />

.... . I ......... ....... . ...\ ............ I. L...........,., **,,.,,."'",L<br />

quintum & kxtum)circa cen- \ ‘IL<br />

&urn mobile 59 Ellipfes,fuas<br />

GJT<br />

‘~~~~~be~e,-~r~p~ius. $& 25. J,<br />

‘&ld$tbk. j;i& empus quarturn 7, “8~ fimili argumerito conclude-<br />

‘fur ‘hoc ‘& .pLiii&urn C ‘Ellip’fes circa omnlum commune centrum<br />

gravitatis B defcribere j maneutibus motibus .priorum xo~p’otluril<br />

7; L & S circa centra 13 & C, fkd paulo acce!ecatis. Et eadem<br />

methodo corpora plura adjungere licebk Z& 23 1.<br />

I&c ita fe habent ubi corpora T & Z rrahunt fe mutuo viribus<br />

acckleratricibus majoribus vei minoribus quam quibus trahunt carpa<br />

r&qua pro ratione difiantiarum. Sunto.mutu;r: omp@ti .sttri&iones<br />

acceleratrices ad invicem ut difiantiz duEkc. m .COI+~O-.<br />

raitrahentia, ,EZ ex pracedentibus facile- dedueetur , quad CO~PQ=<br />

ohlnia 3equalibus.temporibus periodicis -.Ellipfes vwlas 2 .&a om-<br />

Ilium commune gravitatis centrum Bs in @ano immobih @fir+<br />

knt. .&&J$L : L<br />

‘y&Q4


PRINCIPIA<br />

MATE-IEh\/fATICA.<br />

l,fi Propofitione filperiore demonfiratus cfi cafils ubi m~tus piuyes<br />

peraguntur in Ellipfibus accurate. Qo magis recedit Lex vi-.<br />

km a Lege & pofica, eo magis corpora perturbabunt InLltuos<br />

mxus i neque fieri potefi tit CorporaJ kcundum Legem hit pofitani<br />

k mutuo trahentia, moveantur in Ellipfibus accurate, 11% fervando<br />

certam proportionem diitantiarum ab invicem, In fequentibus autern<br />

cafibus non multum ab Ellipfibus errabitur.<br />

42s. I. Pane corpora plura minora circa maximum aliquod ad<br />

.*varias ab eo difiantias revoIviJ cendantque ad fkguIa vircs abfolud<br />

.kz proportionales iifdem corporibus. Et quoniatn omniurn coma<br />

mune gravitatis cencrum (per Legum Coral. quarturn) vel quiefiir<br />

vel movetur uniformirer in dire&urn I fingamus corpora minora<br />

tam parva cffe, ut corpus maximum nunquam difiet fenfibi-<br />

.licer ab hoc ‘centro: & maximum illud vel quieket ve1 mavebitur<br />

,uniformiter in dire&urn, abfque errore fenfibili; minora autem re-<br />

.~ol.ventur circa hoc maximum in Ellipfibus, atque radiis ad idem<br />

cdw!?is defiribent areas temporibus proportionaIes j nifi quarenus<br />

errores inducuntur, vel per ercorem maximi a communi ill0 graviratis<br />

centro, vel per a&ones minorum corporum in fi mucuo. Diminui<br />

aurem poirunc corpora minora ufque donec error ifie & acriones<br />

mutuaz fint daeis quibufvis minores, atque adeo donec Orbes<br />

.ib;um Ellipfibus quadrentJ & areaz refpondeant temporibus, abfque<br />

errore qui non fit minor quovis dare, $ E. 0:<br />

.Cas. 2. Fingamus jam SyItema corporum mmorum modo jam<br />

defcripto circa maximum revolventium, aliudve quodvis d:iorun~<br />

circum Te mutuo revolventium corporum Syfiema progredl w&ormiter<br />

in dire&urn, & interea vi corporis akerius lorlge maximi k<br />

ad magnam difianriam Gti urgeri ad latus. Et q”oniam zquales<br />

vires accelerarrices, quibus corpora ~Gcundum lineas parallelas urgentur9<br />

non mutant fitus corporum ad invicem 3 fed UC Syh1.2<br />

totum, fervatis partium motibus inter fe, fimul transferatur, eficruntz<br />

manifefium eft quad, ex atcraaionibus in corpus maxlmw<br />

x2<br />

nulla


12,~ ?dWr II llulln prorfiis orictur nwt:~ri() fl~~~~ ‘us attrafZkorum inrcr fee, nifi ve1<br />

i; CJ It I’ 0 IL u a1 ex attra&i~onL]m accclcrzltricum irwqualitate, WI ex inchnatione li-<br />

llc;lrLinl ad j~~viccL11, f&JdUi~l qU”S mratiiones fitlllt. Polle ergo<br />

at[rafiiOlleS 0mllcS ?cceleratrices in COrpUS maximum efi inter fe<br />

rccjproce 11~ quadraca difiantiarum j k, augcndo corporh maximi<br />

difiantiam, donec reBarum ab 110~ ad rcliqua CIU&II*LI~I diflkrcnti;E<br />

rc+eLqu earurn Iongitudinis & inclinationes ad inviccm mineres<br />

firIt quam datx qwwis, perfeverabunt motus partirrm Syfiematis<br />

inter i’c :tbfQue erroribrlls qui non fitIt qUibLJfViS datis minores.<br />

Ec quoniam, o b exiguam parcium illarum ab inviccrn clifiantiam,<br />

Syfiema torum ad modwm corporis unius attrahitur ; movcbitmr<br />

j-den1 lxx attraltione ad modam corporis utlius; hoc cfi, cenrro<br />

iilo gravitatis d&Abet circa corpus maximum SeQiot~cm aliquarn<br />

Conicam ( viz. Hyperbolam vel Parabolam nttraQione languida<br />

~1.lipfin forciore, ) 6~ Radio ad maximum du&o dehibet areas<br />

tempcribus proportionales, a bfque ullis crroribus, tlifi quas parrium<br />

difiantlll: ( perexigw fanc & pro hbitu minuetld~) vakant<br />

efficerc. ,.gJ. 0.<br />

Simili arguments pergere keE ad cafiis magis compofiras it] in*<br />

fi11itu111.<br />

Cwol. I. III cab f&undo; quo propius acccd’it corpus c.whum<br />

.rnaximum ad Sytkma duorum vel plurium, co magis turbabuntur<br />

rnotus parrium Syffcmatis inter ie ; propterea quod hearurn a cot?--<br />

pore nwximo ad has du&arum jam major elE- inchatio ad invicem,<br />

majorque proporriouis itwqualitas.<br />

CO~OZ. 2. Maxime autem turbabuntur, ponwdo quad attra&io-<br />

31~s acceleratrices partium Syfiematis verfils corpus omnium maxiznum,<br />

non fiat ad invicem reciproce ut quadrara difiantiarum a<br />

corpore ill0 maximo j prekrtim fi proportioflis hLIjuS inazqualit,zs<br />

major fir quam inzqualitas proportionis d.ifhtiarum a corpore<br />

maximo: Nam fi vis acceleratrix, zqualiter & fkcundum lincas parallelas<br />

agcndo, nil perturbat motUS illtCr fC, flCCCff”c eA ut Cx a&i-<br />

‘onis inaqualitate perturbatio oriatur, majorque fir vel minor pro<br />

ma jore vel minore inaquali ta te. Exccff~~s iinpuIL?wn majorum,<br />

agelYdo in Gq,ua corpora & non agenda in ah3 tiecefirio n%utabunt<br />

fiturn eorurn inter fe, Et IXEC pcrturbatio, addita perturbationi<br />

~ux ex linearam inclinatione & inxqualicate oritur, majorehn<br />

reddet erturbationem totam,<br />

Cwo f . ?;, Unde ii Syfiematis hujus partcsin EllipGbus vel Circ<br />

culis fine perturbatione iniigni movcantur; manifehm efi, qu,<br />

cxdem


u.P, Mo+u uIia tendei~te ad T & oriundaa mutua attra&ione corporum T&F.<br />

h:O~~I’o~~hl N[ac vi fola corplls P circum corpus T, five immotum five llae<br />

attra&kione agicacunh defcribere deberet & areas, radio T’T, tex+<br />

poribus proportionale% & Elliph cui umbilicus efi in centro carporis<br />

T. Patet 110~ per Prop. XI. & Corollaria 2 & 3 TIleOr. XXI. Vis<br />

altera en attrafiionis L illll qua quoniam tcndit a P a! T, tipwaddita<br />

vi ,priori coiilcidet cum ipfi, & fit faciet Ut areX etlamllUm temP<br />

poritus proportionales dcfcribantur per ,corol. 3. Theor. XXI. At<br />

qiloiiiah 11011 eit qtw~r3td difiatititi 2” T reciproce proportionalis,<br />

cbmpollet ~a win vi priore vim ab hat proporttone abc!raarem, idqLle<br />

eo magis q~~omajor eB proportio hLIJLlS ws ad vim prior:em,<br />

czteris ~paribus~ Proinde, cum. ( per Prop. XI, & per Corol. 2,<br />

~heor. +I) vis qua, kllipfis circa umbilicum “I” defcrib$ur tendere<br />

debeat ad ~n~biikxun illum, 8r: e& quadrato difiantia ‘5? T reciproce<br />

Fj~cQjortiofiaIis j vis illa<br />

compofita, a:berrando<br />

ab bat proportionc, fa> .<br />

ciet Lit’ Orbis PA B<br />

abey+t a forfila Eflip- .$<br />

fios unibiktih hab&-<br />

tisin Sj idquc eo magis<br />

quo major eit: abefratio<br />

ab hat propos-<br />

Cone; atque adeo etiam<br />

qLl0 major eiI proportio vis fecundx L iWad vim grimam, ca-<br />

;teris paribus. Jam vero vis tertia S-M, trahcndo corpus ‘P fecun;i<br />

dum lineam ipfi ST parallclaml componet cum viribus prioribus<br />

vim quz non amplius dirigitur a T in T, q~~zq’quc ab hat determinatione<br />

tanto magis aberrat, quanta major efi proportia hujus.tor~<br />

.tia vis ad vires priores, cxteris paribus; atque adeo q,u3c faciet ut<br />

corpus F, radio 27’ 3 areas non amplius temporibos praportiomales<br />

deiiribat, atque aberratio ab hat proportionalitare ut talxosma-<br />

.jor fit, quanto major cfi proportio vis hujus tcrtix. ad vires cxteras,<br />

Orbis vero TAB aberrationcm a forma Elliptica prxf’ata hxc<br />

vis.tertia duplici de caufa adnugcbit, turn quad rlon dirigacur a rip<br />

?d-2; tush etiam $uod non fit proportionalis quadraro diflantix F 2Y<br />

QGbus intellclEEis~ manifcfium eR qwd arcx temporibus turnsmaxime<br />

fiunt proportionales, ubi vis tettia, mauentibus viribus ~g:ke-<br />

AS, fit minima j ,& ciuod Orbis T ~$23 turn maxime acredit ad,przfiitzm<br />

forntarn ~Ellipticam, ubi vhtam ,fecuuda ~ju~m tcrtia, fad prs-<br />

~alpuc vis tcrtia, fit knima3 vi prima m:lne/lte;<br />

Expo-


PRINCIPI’A<br />

MATHEh4AAT’fC:A.<br />

‘Exponatur corporis T attrafiio accekratrix vcrfY,ls J per lillcanl ,<br />

s1\T; k fi attraaiones accelcratrices SM, SN aquaics efl&,t; ha, I\~~~~~~:.<br />

whdo corpora T k T squaliter & fecundqm lineas parallelas,<br />

~1 nwarent firurn eorum ad invicem. fidem jam forent corporum<br />

-kk3rU1~l mOtUS inter<br />

i’e (per Legurn C’orol. 6.) ac fi hx atera&-+<br />

me5 tollerentnr. Et pari ratione fi attra&io SN minor c&r at-<br />

42w%one SlM .tollercr ipfi attra&ionis SAW partem JlT, & ma-<br />

-3wret #pars fola MN, qua temporum &. arearum pl*QPortionali[as<br />

tk 0flbiCZ :forma illa ElJiptica perWr&aretur. Et limiliter fi attrat&ho<br />

SN major e.&t attrahone S i& oriretur .ex dift’ercntia fola<br />

ME perturba.tio ,pxo,portionalitatis & OrbitE, Sic per atrra&jo-<br />

nem SN reducirur fcmper attraho tertia ikperior SM ad attra-<br />

~CKXUZ~ JIXV; a~ttra&ione prima & fecunda manentibus prorhs im-<br />


nGr?<br />

~~~JJJSOPEIIA;. T\ltATURALIs<br />

1) E hb.7 1 ‘I LbroJ, 2, In Syflemate vero trium corporum T, !?J $9 fi attraei-<br />

do 11 I‘ u RLr sI oneS acceIcratrices binmum quorumcunque in tertjum fint ad invi-<br />

,ceM reciproce Llc quadrata difiantiarum; CO~PUST, radlofP2; areaJ1l<br />

circa corpses T velocius defcribec prope Conjuaeionem 4 & Op-<br />

PoGt-oncm 5, quam prope Quadracuras C, fz). Namquevlsomnis<br />

qt1a corpus I’ LJJ -rrei-ur D & corpus T non urgetur, quaeque non agit<br />

{ecull&lm lineal11 Tipr accelerat vel retardat defcriptjonem are%,<br />

.perinde ut ipfi in mnfecpentia vel in antecedentia dlrlgltuc Talk<br />

Ed vis N1\f. HXC in tranfitu corporis T a C ad A rendit in con-<br />

.ikqwentia, motumque accelerat j dein ufque ad I) in antecedentia,<br />

& motum retardat 5 turn in conkquentia ufque ad B, 6~ ultimo in<br />

.antecedentix crant’eundo a B ad C.<br />

CQ~O/. 3, Et eodem argument0 patet quod corpus T, cZteris pa-<br />

-ribus, velocius movetur in Conjun&ione & oppafitione quam in<br />

Qadraturis.<br />

ho&, 4. Orbita corporis T, cazreris paribus, curvier tfi in Qa-<br />

.draturis quam in ConjunEtione & Oppofitione. Nam corpora ve-<br />

Iociora minus deflec-<br />

,tunta reQ0 tramite. Et<br />

.przterea vis KL vel<br />

AIM, in ConjunBionc<br />

& Oppoficione, con- $<br />

fraria efi vi qua corpus<br />

Ttrahit corpus T,<br />

-adeoque vim illam mi-<br />

XiUit j corpus autem F<br />

minus de&Ret a re&o<br />

,tramite, ubi minus urgetur in corpus ‘T.<br />

CoroC. 5. Unde corpus Tip, czteris par&us, longius recedeta carpore<br />

T in Qadraturis, quam in Cu~~jun&ione&Oppofitkme. I&c<br />

ita k habent exclufo motu Excentricitatis. Nam fi Orbita corpo-<br />

.ris P excentrica fit: Excentricitas ejus (ut mox in hujus C&o]. 9,<br />

x3fiendetur) evadet maxima u bi Apfides funt in Syzygiis j indeque<br />

fkri .po.tefi ut corpus T, ad Ap.fidem fummam appellans, &fit lollgius<br />

a corpore “2” in Syzygiis quam in Qadraturis.<br />

Cofwl. .6. C&oniam vis centripeta corporis centralis T, qua car-<br />

‘Pus 13 retinetur in Qrbe fuo, augetur in Qadraturis per ad&&-<br />

nem vis Lf?& x dim@uitur in Syzygiis per &lationem vis KL, &<br />

~b magnitudinem vis K %I, magis diminuitur quam augetur j ee au-<br />

;tem VIS illa centripeta (per Coral. 2, Prop. IT.> iI] ratione compo-<br />

Jita Ed ratione fim$itii radii TT dire&e & ,ratione duplicata tempo-<br />

ris


PRINCIPIA MATWEMATI~A~ 1Gr<br />

ris periodici inverk: paw hanc rationem compo~ta~ dinlillui per ; ‘I 7,<br />

a&k&m Vis ICE, adeoque tempus period&m, fi ma,IcLt ~~~~~~ 11 I4 II<br />

radius Tp, augeri, idque in iilbduplicata rationc qua vis illa ccrIrfipeta<br />

diminuitur : aufioque adeo vel diminuto hoc Radio, eclIz..<br />

pus t3criodicu.m augeri magis, vel diminui minus qualn in Radii ilen-<br />

Jus ratione fefquiplicata, per Corol, 6. Prop. 1~. $ vis il[J coryoris<br />

centralis paulatim languefcerer, corpus T minus ikmper ‘c; nlinhns<br />

~~~r~~um perpetuo recederet longius a centro 27; ‘& contra9 fi vis<br />

illa abgeretur, accederet propius. Erg0 G a&io corporis ~or;ginqui<br />

3, qua vis illa diminuitur, augeatur 11c diminuatur per vices;<br />

augebitur fimul ac diminuetur Radius TP per VLCC-$, k ecnlplls peL<br />

riodicum augebitur ac diminuetur in ratione cornpofir:l cs ratiolIe<br />

Gfquiplicata Radii & ratione &bduplicata qua vis i\Ia centripcca<br />

corporis centralis T, per incrementum vel decremencum ;~&ionis<br />

corporis longinqui S, diminuitur vel augetur.<br />

Carol. 7. Ex pramiffls conkquitur etinm quod Elllipfe~s a c(prpore<br />

T defcriptg Axis, Ceu Apfidum l&a, quoad motum angula*<br />

rem progreditur & regreditur per vices, fed magis tamen progreditur,<br />

84 in iingulis coryoris revolutionibus per cxce(lirm progrcC<br />

. fionis fertur in conkquentia. Nat-n vis qua corpus fp u~getur irn<br />

corpus T in Qadraturis , ubi vis MN evanuit, componltur e-x vi<br />

1; M & vi centripetaqua corpus T trahit corpus T. Vis prior L k5<br />

fi augeatur difiantia T Z-, augetur in eadem fere ratione cum hat<br />

difiantia, & vis pofierior decrefcit in duplicata iila ratione, ackoque<br />

fumma harum viriuni decrefcit in n$nore quam dupticata ra.-<br />

tione difiantitr: T T, & proprerea (per coral. I. Prop, X LV) &kit<br />

UC Aux, fcu ~pfis fumma, regrediatur. In Conjuni-:tipne vero &z<br />

Oppo~t~or~e, vis qua corpus T urgetur in corpus T dtfferencia elk<br />

inter vim qua corpus T trahit corpus T &Z vim KL j Sr ditkrew<br />

tia illa, propterca quad vis KL, augetur quarnproximc in ratione<br />

&fiantix bp r, decrefcit in majore quam dupl$ta rat&X. difiantiz<br />

cp T, &oque (per Coral. I. Prop. XLV) efhclt Ut Aux progrediatur.<br />

In loeis &tcr Qzygias 6% Qadraturas pendet motw AU-<br />

&is cx cauh utraque conjun&im, adeo ut ro hujus vel alterius<br />

exceru progrediatur ipfa vei regrediatur. s nde cum vis KL in<br />

syzygiis iit quafi duplo major quam vis L M in Qadraturls, esceflus<br />

ill tota revolutione erit penes vim K L3 tr:~~~sfer~tcluc 4u-<br />

gem ~~gulis revolutionibus in conkquentia. Veritns nucem hu]us<br />

&- pracedentis CorolIarii facilius intellir;etur concipiendo Syitelna<br />

corporum duorum 7; T corporibus pluribus S, S, S, 8~ l?,()v<br />

be: ;E 8~ confilt_cntibus, undique$ngi. Namque hum a&la;:; u


16% p~~fxxxx-Wr~ NATWRAus<br />

I;)~ MOT u t.>~s a&h ipfius T millaetur undique, decreketque in ratione phi’-<br />

c ~RPUI~ 1j h1 quam duplicata difiantix.<br />

CO&. 8. Cum autem pendeat Apiidum progrenirs vcl regreffus<br />

a decremenfo vis centripcttl: fa&o in majori vel mhori quam duglicata<br />

ratione diltantia TT, in tranfitu corporis ab Apfide ima<br />

ad ApGdem fhnmam > ut St a fimili incremcnro in reditu ad Apiidem<br />

illlZl~ll j atque, adeo maximus fit ubi proportio vis in. Apfide<br />

~,~~mmad vim in Ap.i’ide ima maxime recedit a duplicata ra,tione<br />

difiantiarum inverfa : manifefium cfi quad Apfides in Syzygiis..<br />

ikis, per vim ablatiriam I< L kccu A?M-- PI M, progredienc+uf VClocius,<br />

inque Quadra&s his tardius recedent per vim addltltiam<br />

k; &‘. Ob diutuhitatcm vero temporis quo velocitas progreffus vel<br />

garditxs regreffirs continuatw fit lwc in3equalitas Ionge maxima.<br />

~aroj. 9, Si corpus aliquod vi reciproce proportionali quadracw<br />

diftantize tux a ceijtro, revolveretur circa hoc centrum in Ellipfi,<br />

& mox, in defcenh ab Ayfide fumn? Cell Auge ad Apfidem<br />

imam, vis illa per weirurn perpetuum vls now2 augeretur in raw<br />

aione phfquam du plicata<br />

ciiltatltize dimhutc7:<br />

: inanifefium Cfi<br />

quad corpus) pcrpe-<br />

$uo acceffi vis illius<br />

now impulfum femper<br />

in cenCcum, magis<br />

vergeret in hoc celltrum,<br />

‘qua” ii urgeretur<br />

vi .fola crci‘cente<br />

.._<br />

in duplicata ratione difiantia? diminut;te, adeoq,tlc Orbcm dcl’criberet<br />

Orbe Elliptico interiorcm, 8r in Apfidc lma propius accc-<br />

&ret ad centrum quam prius. Orbis igitur , acceflu hujus vis noa<br />

vx, fiet magis excentricus, Si jam vis, in recc’ffu corporis at,<br />

Apfide ima ad Apfidem fi~mmam~ decreficret iifdem gradibus quibus<br />

ante creverat, redirct corpus ad difiantialzz priorem, adcoquc<br />

fi vis decrefiat in majori, ratione, corpus jam nunus attra&um afcendet<br />

ad .dihntiam majorem & fit Orbis Excentricitas adhc ma*<br />

gis au ebitur. I&w fi ratio incrementi & decrementi vis cent&<br />

peta: f; mgulis rcvolurio~~ibus augcatur 9 augebitur fimpcr Excel~tricitas;<br />

8tr e contra, diminuetur eadem fi ratio illa decrcfcat, Jam<br />

vero in Syfiemate corporum 2, T, 5’, ubi ApGdes Orbis 50 A.#<br />

liwt in C&acIraturis, ratio. illa incrementi ac decrement$ minima efi,<br />

; ! &.e


p)RIfd CIPIR MATI-IEX~IAT~CA. I G’ j<br />

8~ mak~a fit ubi Apfidcs funt in Syzygiis, Si AP~dcs con~icu3u- ;<br />

tUr in Qk!adratLlris, ratio prope Api’ides njinor eft &- prope‘ srzT~- f”. .‘,I<br />

‘@as major quatll duplicata difiantiarum, & cx ratione iil;t ,~~;ii&<br />

-.-oritur Augis torus velocifimus, uti &I, diQum efi. At ii Coilfideretur<br />

ratio incrementi vel decrementi totius in progrcoil inrcr<br />

APfidesj 11~~ minor efi quam duplicata dihntiarum. Vis 111 ~i”.~<br />

Aide ima efi ad vim in Apfidc fiimma in minore .qua” duP\ic,lta<br />

ratiolIe difiantix Apfidis futnmt~ ab unlbi[ico Eilipfeos ;;J tjifimiam<br />

Apfidis imz ab eodem umbilico : k e contra, u:ll<br />

.+pfides confiituuntur in Syzygiis, vis in Apfide ima efi ad vim<br />

%n Apfide fiunn~a in majore quam duplicate ratione diltanti;lrum<br />

*&fam vires L ik? in Qadraturis additx viribus corporis 7” componunt<br />

vim in ratione minore, 62 vires KL, in Syzygiis f~‘od~.&~<br />

viribus corporis T relinquunt vires in ratione majorc. Eli isktar<br />

ratio decrementi & incrementi totius, in tradh inter Aphh,<br />

minima in Qadraruris, maxima in Syzygiis: et propterea in tramiitu<br />

Apfidum a Qadraturis ad Syzygias perpetuo augetur$ augetque<br />

Excentricitatem Ellipfkos j inque tranlh a SyzygiiS ad<br />

QLuadraturas perpetuo diminuitur, & Excentricitatem dimmuk<br />

Coral. IO. Ut rationem ineamus errorum in Latitudincm, fiug.~-<br />

IIIUS planum Orbis .fZST hnobile manere; & ex errorum expofita<br />

caufa manifefium et? quad, ex viribus NM) ML, qua fht<br />

- ,caufa illa tota, vis ML agenda femper Eecundum planurn Qrbk<br />

SPA B, llunquam perturbat mows in Latitudinem ; quodque visNLlil;<br />

ubi Nodi funt in Syzygiis, agcndo etiam Secundum idem Orbis<br />

planum, non perturbat has motus; ubi vero fiunc.in Qadraturis<br />

e0.s maxime perturbat, corpucque P de plano Orbis fui perpetuo<br />

trahendo, minuit inclinationem plani in tranficu corporis a &I-<br />

,&aturis ad-syzygias, augetque vicifim eandem in tral1fit.u a Syzygiis<br />

ad Quadraturas. Uncle fit ut corpore in Syzygiis exritente HI-<br />

,clinatio evadat omnium minima, redeatque ad priorem magnitudillem<br />

circiter? ubi corpus ad Nodum proximum accedit. At fi Nodi<br />

..conft-tuantur in O&antibus pofi Qadraturas, id eh inter c k J&<br />

m.. & g, inteliigetur ex mode expolitis quad, in trapfit? cqrporis<br />

I) a Nodo alterutro ad gradum inde nonagefimum, whatlo pia-<br />

..ni perpetuo minuitur ; deinde in tranfitu per proximos 45: gradus<br />

%pfque ad Quadraturam proximam, inchatio augetur, & po@J denuo<br />

in tranfitu per ahos 4.5 gradus, ufque *ad Nodurn Pr*xfmumr<br />

diminuitur. Magis itaque diminuitur inchatlo quam 3~2;ctur~ &<br />

,propterea lninor efi fernper-in yo,d” lubbrequente q*am 10 Prgcea<br />

dente.


I).]: :lI,,T 1: den&, Et fimi]i ratiocinio, inclinatio magis augetur quam chin&<br />

c: (,, ii I I) n u 3 tur ubi N& fwlt in O&anribus alteris inter A Sr: 23, B 6-c C. Inclillatio<br />

jgitur ubi Nodi funt in Syzygiis el1 omnium maxima. In<br />

traniitu corum a Syzygiis ad Qadraturas, in hgulis corporis ad<br />

Nodes appullibus3 dmhuitur, firque omnium minima ubi Nodi<br />

iitllt ill Qadraturis & corpus in Syzygiis: dein crefcit i$em gradibus<br />

quibus antea decrevcrat, NodiTque ad Syzygias proxlmas appulfis<br />

ad magnirudinem primam revertitur.<br />

Carol. 1 I. Quoniam corpus T ubi Nodi funt in Qadraturis perpetuo<br />

trahicur de plan0 Orbis fiui, idque in partem vcrfus S, in<br />

CranJitu file a Nodo C per ConjunEt-ionem A ad No&m 59 5 & in<br />

contrariam partern in tranku a Nodo 59 per Oypofitjonem B ad<br />

No&m C; manifefium efi quad in motu fiio a Nodo C, corpus<br />

perpetuo recedit ab Orbis fui piano primo CB, ufque dum perventurn<br />

efi ad Nodunl proximum j adeoque in hoc Nodo, longhEme<br />

difians a piano illo primo CD, tranfir per planun~ @his EST<br />

non in plani illius Nodo alter0 13, fed in pudto quad in& I-W@<br />

ad partes corporis S, quodquc proinde novus efi Nodi locus in anreriora<br />

vergens, Et: fimili argument0 pergenc Nodi recedere in<br />

sraniitu corporis de hoc Nodo in Nodum proximum. Nodi igirur<br />

in Qadraturis confiituti perpetuo recedulltj in Syzygiis (u&i<br />

motus in Latieudinem nil perturbatur) quiefcunt 5 in locis internterfiis,<br />

conditiolkis urriafque participes, recedunt tardius ; adeoques<br />

1 Gmper vel retrogradi vcl fiationarll “) fihlguIis revolutiolaibus feruntur<br />

in antecedentia.<br />

Coral, I 2. Omnes illi in his Corollariis dekripti Errores funt pauc<br />

IO majores in Conjuntiione corporum T, 8 quam in eorum Opl,<br />

pofitione, idque ob majores vires generantes NM & ML,<br />

COPOL 13, Cumque rationes horum Corollariortim non pendeant<br />

a magnitudine corporis S, obtinent pr‘azcedentia omnia, ubi corporis<br />

Stanta itatuitur magnitude ut circa iphm revolvatur coryorum duorum<br />

T & !P Sykema. Et ex au&o corpore S autiaque adeo ipfiws<br />

vi centripeta, a qua errores corporis T oriuntur, evadent. errores j]&<br />

omnes (paribus difiantiis) majores in hoc cafu qwm in. altero, u&<br />

corpus S circum Syftema corporum 5? & T revolvitur.<br />

Cwol. x4. Cum autem vires NM, ML, ubi corpus S Ion&<br />

quum efi, fint quamproxime ut vis,SK & ratio T T ad J’T COINjun&im,<br />

hoc eR, ii detur turn difiantia, 5? T; turn corporis: 3 vis<br />

abfooluta, ut ST Gtik reciproce j fine autem vires ilk ATM, MA<br />

cauk errorum & effek?wm omnium de quibus.aBum efi in .przc~..<br />

CkmibU~


P~I~KXI)IA MATHEMATKXk. I.45 f<br />

d&bus Corohriis: manifefium efi quad eFec?cus illi onms, Ban- ~10 ER<br />

tc corporum T & T Syflemate, & mutaris tantum difianria ST & P131hfUs*.<br />

vi abfoluea corporis S, hc quamyroximc in ratione conrpofica ex<br />

ratione dire&a vis abfolutz corporis S & ratione triplicata inverh<br />

difiantk S*T Wade fi Syfiema corporum T & T revolvatur circa<br />

corpus !on$+~quum 8, vires ills NM2 ML Sr earum eft‘eEi:us<br />

erwt (per C&ol. 2. 3i: 6. Prop. IV.> reciproce in duplicata ratione<br />

temporls periodici. Er inde etiam, ii magnitudo corporis S proportionalis<br />

fit ipfius vi.abfollltz3 erunt vires ilk2 NiV, ML & earum<br />

eft’eh-us diretie u t cu bus diamctri apparentis Ionginqui corporis S e<br />

corpore T fpe&ati, Sr vice verfia. Namque 1132 rationes cLedcm hunt<br />

atque ratio fiperior compofita.<br />

Cowl. IF. Et quoniam ii, manentibus Orbium E $IE & TAR<br />

forma, proportionibus & inclinatione ad invicem, mutetur eorum<br />

magrlicudo, & ii corporum S & r vel maneant vel mutentur vireo<br />

in data quavis ratione,<br />

ha2 vircs (hoc eit,<br />

vis corpdris Tqua corpus<br />

T de reQo tramite<br />

in Orbitam TAB<br />

defle&ere, & vis corporis<br />

S qua corpus<br />

id’em T de Orbita illa<br />

deviare cogitur) agunt.<br />

33,<br />

kmper eodem mo-<br />

do & eadem proporrione: lleceffe efi ut iimiles & proportionales<br />

finr efYe#us omnes & proportionalia eEerttuum tempora j ‘hoc<br />

efi, ut errores omnes lineares ht ut Qrbium diametri, nngulares~<br />

vero iidem qui prius, & errorum Iinearium fimihum vehgularium<br />

xquaiium tempera ut Orbium tempora periodica.<br />

CQP~/. 16. Unde, ii dencur Orbium form% & inclinatio ad’itivicem,<br />

& mutencur utcunque corporwm magnitudines, vires & diifant&;<br />

ex dark erroribus & errorum temporibus in uno Cafu, COIL<br />

Ii@ porkIt errores & errorurn rempora in ah quovis, quam pro;<br />

xime.: Sed brcvius hat Methodo. Vires NM, ML, czceris fian:<br />

ribus, {unt ut Radius TT, & harum &e&us periodici (per CoroL 4<br />

]Lem; x) ut vires & quadraturn temporis periodici cqrporis T conjun&:im.<br />

Hi font: errores lineares corporis .‘T; 8r, I?mc errores an&<br />

pIares e centro I? +Bati (id efi, tam mptus Aug~s & Nodorum,<br />

quam omnes in kongit~~dinem & Latitudinem errores qyarentes)<br />

. ifunt> in qualibet Jewlutione* corporis. a>, ut qnadrhin temporls +<br />

revcly


$736 I)t-iUfEKGHHX NATURAL IS<br />

14,<br />

T4 E M OTIJ revoltitionis quanl proxime. Conjungantur h;z: rationes cum ratio-<br />

~~~~~~~~~~~ niblls Corollarii & in quolibct corporum T, T9 S SyfklllkW%<br />

ubi P circum T fibi propinquum, & T circum S longinquum revolvitur,<br />

errores angulares corporis T, de centro T apparentes,<br />

erutlt, in fingulis revolutionibus corporis illius T, ut quxkmm<br />

tcmporis pcrlodici corporis T dire&e & quadratum temporis periodici<br />

corporis T invcrfe. Et inde motus medius Au@ &tin data<br />

ratione ad mown medium Nodorum; & motus uterque erit ut<br />

quadraturn temporis periodici corporis T dire&e & qtiadratum<br />

temporis periodici corporis T inverie. Augendo vel minuend0<br />

Excencricitarem & Inclinationem Orbis TAB non mutantur mo-<br />

QUS Augis & Nodorum finfibiliter, nifi ubi ezdem fint nimis<br />

magnz.<br />

CoraL 17. Cum autem linea L M nunc major fit nunc minor<br />

quam radius T T, exponatur vis mediocris L M per radium illum<br />

T 2; & erit hec ad<br />

vim mediocrem SK<br />

34 SN (quam exponere<br />

licet per ST) ut<br />

longitude T T ad longitudincm<br />

ST. Efi autern<br />

vis mediocris SN<br />

vel ST, qua corpusT<br />

retinetur in Orbe fro<br />

circum S, ad vim qua<br />

y~orpus T retinetur in Orbe Qo circum T, in rarione compofita ex<br />

ratione radii 5 Tad radium T I, & ratione dupIicata temporis periodici<br />

corporis T circum T ad tempus periodicum corporis T<br />

circum S. Et ex xquo, vis mediocris L M, ad vim qua corpLls<br />

fp rerinetur in Orbe fro circum T ( quave corpus idem T, eodem<br />

tempore periodico, circum pun&urn quodvis immobile 2 ad.<br />

difiantiam T T revolvi poffet) efi in ratione illa duplicata period&<br />

-coTurn temporum. Datis igitur temporibus periodicis una cum difiantia<br />

T 2-3 datur vis mediocris L Mj & ea data, datur etiam vis<br />

&2.iV quamproxime per analogiam linearum T T’ MX<br />

Coral. 18. llifdeti legibus quibus corpus T circum car us T r+<br />

.volvitur 9 fingamus corpora plura fluida circum idem 8 ad aequales<br />

ab ipfo diltantias moveri 5 deinde ex his contiguis faQis confla..<br />

ri Annulum fluidurn, rotundum ac corpori T concentricua; &<br />

.fing& An&i partes, rnotus fuos omnes ad kgem cqrporis T er.<br />

age x do,


age=b propius accedenr ad corpus T, & celerius nlovehuntur L I I! E R<br />

ill Conjun&ione SC: Oppofitione ipfarum & corporis $, qurlm in PKIXVE.<br />

Q7adraturis. Et Nodi Annuli hujus keu interfe&iones ejus cum<br />

plan0 Orbit:r corporisJ$ vel T, quiefcent in Syzy.giis; extra Syzy-<br />

@as vero movebuntur in anteccdentia, & velocttEme quidem In<br />

Quadraturis, tardius aliis in lock. Annuli quoque inclinatio variabitur3<br />

SC axis ejus fingulis revalutionibus ofciliabitur, completaque<br />

revolutione ad priftinum fiturn redibit, nifi quatenus per prac&-<br />

onem Nodorum circumfertur.<br />

Coral. 19. Fingas jam Globun~ corporis T, ex materia non fluida<br />

confiantem, ampliari & exrendi ufque ad hunt Annulurn, & alveo<br />

per circuitum,excavato contincre Aquam, motuque eodem pcriodice<br />

circa axem fi7um uniformiter revolvi. Hit liquor per vices<br />

acceleratus & retardatus (ut in fuperiore Corollario) in Syzygiis<br />

velocior wit , in euadracuris tardior’ quam -fuperficies Globi, &<br />

fit fl~7et ‘in alveo reflnetque ad modum hlaris. Aqua revolvendo circa<br />

Globi centrum q”iefcens, li rollatur attraRio corporis S nultum<br />

acquiret motum fluxus S= refluxws. Par et? ratio Globi uniformiter<br />

progredientis in diretitum & in terea revolventis circa ten trum<br />

fuum (per .Legum Coral, 5.) UC & Globi de cut57 re&ilineo uniformiter<br />

tra&i, per Legum Corol. 6. Accedat autem corpus S,<br />

& ab ipfius.inxquabili atrraAione ?ox turbabitur Aqua. Ecenim I<br />

major erit: attraCti aqus propiorls, minor ea remorioris. Vis<br />

autem .I, n/r trahet aquam deorfum in Quadraturis, facietque ip-<br />

$am dekendeee uI?que ad Syzygias; & vis KL trahct eandem fiirfam<br />

in Syzygiis, fifietque defcenfum ejus & faciet .ipkm akendere<br />

ufque ad Qadraturas.<br />

Coral. 20. Si Annulus jam rigeat 82 minuatur Globus, ceirab<br />

bit motus fluendi & refluendij fed Ofiillatorius ille inclinationis .<br />

nIotu~ S; przcefio Nodorum manebunt, Habeat Globus eundem<br />

axem cum Annulo, gyrolque compleat iifdem temporibus, & fuper-.<br />

ficie cua contingat ipiilm interius, eique inhxreat; Sr parcicipando<br />

m0tum ejw compages<br />

Annuli<br />

urriufque Ofcillabitur & Nodi regredientur,<br />

-Nam Globus, ut mox dicetwr, ad fukipiendas imprelliones,<br />

Omnes indifferens efi. Glob0 orbati maximus inclinationis<br />

angnlus e@ ubi Nodi f~7nt in Syzygiis, Indc in progreiru NodorunI<br />

ad Quadraturas conatur is inckM.ionem ruam minuere, & ifio<br />

conaru motum imprimit Globo toti. Retinet Globus motum imgr.efum<br />

ufque dum Annulus .conatu cantrarlo motum h~nc tollat.~<br />

imprimatque motum novt7m In contrariam partem: Atque ha! ratLone


1) n, bl,2 1 ,, tione maximus decrcfcentis inclinationis motUs fit in QUadratUriS<br />

LIO:PO~;E!I Nodorum , & mi&uS inclinationiS angulus in CXkwtibus po&<br />

Quadraturas ; dein maximus reclinatiqnis mOtUS in syzygiis, &<br />

nlaximus angulus in OL%antibus proximls. ,Ft eadem efi ratio GI+<br />

I_li Alll~ulo nudati, qui in regionibus ZqUa%-kis Vel altior eft paulo<br />

qum juxta poloS3 vel confiat ex materia paulo denfiore. sup.<br />

@et enim vicem Annuli iite mat&z in zqUa+tori~ regionibus excefiilponantur omnes ejus partes deorfUm> ad modurn gravir~~~ciUrn<br />

partium telluris, tamen Fbanomena hjus & pracedentis<br />

Corollnrii vix inde mutabuntur.<br />

Coral. 21, Eadem ratione qua materia Globi juxta aquatorem<br />

aedundans eflicit ut Nodi regrediantur, atque adeo per. hujus incrementum<br />

augetur ifie regreffLw, per diminutionem vero diminuitUr<br />

& per ablationem tOlIitUr j f+ materia plufquam redundans toI-<br />

Iatur, hoc eR, ii Globus juxta zquatorem vk.1 depreifior reddatur<br />

vel rarior quam juxta poloS, orietur motus Nodorum in coilfiquentia.<br />

Cowl. 22. Et inde+viciQim, ex motu Nodorum innotefkit confiicutio<br />

Globi. Nimirum ii Globus poles eofdem conRanter fervat,<br />

& motus fit in antecedentia, materia juxta aquatorem redundat;<br />

ii in conkquentia, deficit. Pone Glcbum uniformem & perktie<br />

circinatum in fpatiis liberis primo quiefiere; dein impetu qLtocunque<br />

obIique in hperficiem fuam faQo propelli, & motum inde<br />

concipere partim circularem, partim in dire&urn.-. Qoniam .Glo-<br />

:bus ifie ad axes. omnes per centrum fuum tranfeuntes indifferenter<br />

fe habet, neque propenfior efi in unum axem, unumve axis ‘fitumj<br />

quam in aliLlm quemvis j per+icuulG ef% quad is axem.fUum axif:<br />

que inclinationem vi propria nunquam mutabir. Impellatur jam<br />

Globus oblique, in eadem illa fuperficiei parte qua prius, impulfu<br />

quocunque nova; & cum citior vel @ior impulfus effeQun1 nil<br />

mutet, manifeitum efi quod hi dUo impulfus fucceilive imprea<br />

eundem producent motum ac G fimul impreffl fuiffent, hoc kfi,<br />

eundem ae fi Globus vi limplici ex utroque (per Legum Core]. 2,)<br />

.compofita impulfiis fuiiret , atque adeo fimplicem , circa axem ina<br />

clinatione datum. Et par efi ratio impulfus kundi fa&i in IOcum<br />

alium quemvis in azquatore motus primi j ut & impulfus pri;<br />

mi fa&i in locum quemvis in zquatore motus, quem impulfis f&<br />

cunduS abfque primo generaret j atque adeo impulfuum amborum<br />

.Mk2kwn in loca quzrcunque : Generabwt hi eundem rnatum ci>rcwkkem


cularem ac fi fimul & fifemel in locum interi‘efiioilis qwc~tx~ 1.. : 1: i *<br />

motuum illorum , quos feorfim generarent, fuiiknt impr&<br />

Globus igitur homogeneus & perfefius non retinet motus p~ures<br />

diitin&os, i‘ed impreffos omnes componit & ad unum reducit, &<br />

quatenus in k eR, gyratur femper motu fimplici & uniformi circa<br />

axem unicum, indinatione femper invariabili datum. Sed ncc vis<br />

centripeta inclinationem axis , aut rotationis velocitatem mutare<br />

pot&. Si GEobus piano quocunque, per centrum lilum & tenfrum<br />

in quod vis dirigirur tranfeunte,dividi intelligatur in duo hennifphzeria<br />

5 urgebit kmper vis illa utrumque hemifphzrium aqua*<br />

liter, & propterea Globum, quoad motum rotationis, nullam in<br />

partem inclinabit. Addatur vero alicubi inter polirm & aquatorem<br />

materia nova in formam montis cumulata3 & hrc, perpetuo<br />

conatu recedendi a centro I%i motus, turbabic motum GIobi, faall<br />

cietque polos ejus errarc per ipfius iilperficiem,. k circulos circum<br />

ti pun&umque fibi oppoiitum perpetuo dekribere. Neque corrigeeurifia<br />

vagationis enormitas, nifi locando montem ilium vel in polo<br />

alterutro, quo in Cafii (per Coral, zx) Nodi azquatoris progrediewtur;<br />

vel in azquxtore , qua ratione (per Coral. 20) Nodi regredientur;<br />

vel denique ex altera axis parte addend0 materjam novam,<br />

qua mans inter movendum libretur, & hoc patio Nodi vel pro-<br />

gredientur, vel recedent, perinde ut mans & hwce nova mareria<br />

Cunt vel polo vel zquatori propiores.<br />

_ PROPOSITIO LXVII. THEOREMA XXVII.<br />

PO&S i$dem attraEionum legibus, &co quad corps exterim So<br />

circa int&ortlti P, T corrmwne graruitadis centrum c, radik<br />

ad cenmm dhd dtifi%, deJcribit mea5 tempo&m magti proportionales<br />

& ~rbem dd formam HZpJeos mnbilhxm i~z centro<br />

eodem habentis ma@ accedclatem, quam circa corpm intimm<br />

& mm&num T, radiis dd ipJTm dh%, deJcribere poteD.<br />

Nam corporis 5’ attraaiones verfus T& T componunt ipfius attra&ionem<br />

abfolutam, quz magis dirigitur in corporum T& T commune<br />

gravitatis centrum C, quam in corpus maximum T, qwque<br />

quadrato difiantix SC magis efi proportionalis reciproce, quam<br />

quadrato d&u&-57: ut rem perpendenti facile confiabit.<br />

25 PR..o--<br />

I’ i: 1 hi ‘.’ *


P~OI’OSITIO LXVIII. THEOREMA XXVII:,<br />

~OJitis iiJdern nttru&onum legibus, dice quad corpw exteriw sJ<br />

circa interiorurn I? & T commune grawitatis Gentrum C, rd.<br />

d$s ad centrum il%d dzk%s, deJcribit -urea tewporibus PZQ@<br />

proportiolzahs, & Orbenz ud formaw .&TipJeos umbilicus iq<br />

cmtro eodem habentis ma&s accedentem, Ji corpus k&urn &<br />

rmximm his attraEio&h perinde atque cgteru agitetw, Qume<br />

Ji id cue1 non attra&m guieJcat> we1 m&o vagis aut v&to<br />

sninus attra&m aut nzulto ma&s atit mu&o mkzks agitetw.<br />

Demonftratur eodem<br />

fere modo cum<br />

Prop. LXVI, f@l argumento<br />

grohyiore,<br />

quod idea prxtereo.<br />

Sutiecerit rem fit 376<br />

mare. Ex demonffra-<br />

Gone Propofitionis<br />

noviffimle liquet centrum<br />

in quad corpus<br />

3.3<br />

S-conjun&is viribus .urgctur, proximum effe communi centro gravitatis<br />

duorum illorum. Si coincideret hoc centrum cum centro<br />

ill0 cb117muni3 & quiekeret commune centrun~ grav.ka& corporum<br />

triuxn j defcriberent corpus ,S ex una paw9 & commune centrum<br />

aliorum duorum es altera parte, circa commutne omnium centrum<br />

‘quiefcens, Elhpfes accuratas, Liquet hoc per Corollarium ficundum<br />

Propofitionis LVIII collatum cum demonfiratis in Propof:<br />

&XIV .& LX;Y. Perturbatur iite mbtus Ellipticus Jiquantulum.per<br />

difiantnml centri duorum a centro in quad terrium $ attr&,itur.<br />

Detur praterea motus communi trium c&ltzro, & augebitur per-.<br />

turbatio. ,Proinde minima efi perturbatio ubi commun~e +riurn<br />

centrum quiekit, hoc elt, ubi corpus intimum & .maximum T Iege<br />

czterdrum attrahitur : fitque major femper ubi trium co,m,mune ilr<br />

Iud centrum j minuendo, motunz corporis T, moveri ‘incip$ .& IJ+<br />

gis deinceps magifque agi.tatur,


PRINC A~~EMA~~C~, ‘2’<br />

Chord, Et IGnc, ii corpora plura minora wlolvantur circa maxi- f,f ,J l: c<br />

mum, colligere licet quod OrbitE defcriptaz firopius accedcnc ad l’~tr ;>I’; 3,<br />

Ellipticas, & arearum dekiptiones fient magis azquabiles, Ii corpora<br />

omnia viribus acceleratricibus, quz i’unt ut eorum vires abfolutae<br />

dire&e & quadrata difiantiarum inverfe, fe mutuo rrahant<br />

Pgitentque, & Orbita cujufque umbilicus collocetur in communi<br />

centro gravitatis corporum omnium interiorum (nimiruni umbk<br />

.Mks Orbitre prima: & intimx: in centro gravitatis corpork maximi<br />

& intimi; ille Orbit% fecunde, in communi centro gra+il<br />

tatis corportim duorum intimorum; ifk tertiz, in comtiutii cenei6<br />

gravitatis trium interiorulil ; & iic deinceps) quam ii Corpus<br />

inti)tkluti quiefcat & itatuatuf communis umbilicus Orbn.rum<br />

omnium.<br />

PIio’POsITIO LXIX. ‘T’I-IEOREMA XXIX.<br />

if’ Sypemate corporwm phkmz A, B, C, D, &IT. J; COQIUS aliquod<br />

A twhit atera omliia B, C, D, &c. viribus accehatricibus<br />

gti~8 J&t reciproce tit qtiahata d~$antiaruf&z d trdhente j &<br />

corpus t&d B trabit et&z cLetem A, C, D, &SC, v&ibw qwg<br />

Jint ~ciptoce tit qtiddputa dz$&mm a kbente : ertint Abj?olz@d<br />

corpomm trahetithn A? B zlires ad inzricem, tit JbG<br />

ipJu corpora A, B, quorm sunt wires.<br />

Nam attra&iones acceleratrices corporum omnium B, C, I) ver-<br />

%‘US A, paribus diitantii& fibi invicekn kqwantur ex Hypothefi j &<br />

fimiliter attra&iones acceleratrices corporum omnium verfu8 BP<br />

ijsribus difiantiis, fibi invicem zquantur,’ EB autcm abfoluta vis<br />

atM.&iva corpdris A ad vim abf~~uratii,att~a,~ivam corpo’fis Z?, ut<br />

&tra&i6 acceleratGx ctirpofum c%+&%rn verfils A, zd altra&kmcm<br />

akk~lef~tricem corportim o&Gum J+‘I%IS B, @ribus difiantiis; &:<br />

ita tifi attra&io acceleratrix corporis-I3 vei%u$ A, arl attra&ionem<br />

ack%3!atricem corporis A ver$us:B, Sed attraRio acdeleratrix corpork<br />

B perfus A efi ad attrk%ollerk ac&e’ratrice~ corporis, A<br />

qeriirs’ .B, ut ti’afi corporis A ad mafim‘ corporis B; proptefea<br />

q@d t’ires matrices , quaz (per Dc3iGitionem lececundam’, kptirii;em,<br />

82 o&vam) ek Viribtis acceleratricibus in corpora’ attraaa<br />

8u&is oriuntur, funt (per motus Legem tertiati) fibi iniricem azquaq<br />

z;?<br />

lCS,


His Propofitionibus manudbcimur ad analogiam inter vircs cclzs<br />

tripctas 6ir corpora centralin, a d qu;x: vircs ill,?: dir&i folcnr. Raw<br />

tioni cnim co17htancum CR, ut vircs qil8-2 ad corpora dirigweur<br />

pendcm nb cor~ndem mum & quantitnrc, uc fit h M~gncticis,<br />

Et quorics hujufhodi cafils hcidunt , aftimandx crunc corporun~<br />

attra&ionC~ J aflignando hgulis corum particulis vircs proprias,<br />

& colligendo humas virium. Voccm Artra&ionis Ilk<br />

ufiwpo pro corporum con;ltu quocunque acccdcndi *1<br />

Gve conatus ii2e fiat ab a&ione corpc.wmh vcl [c: mLWo pCECntiuml<br />

vcl per Spiritus cmiffbs Cc inviccm agirantiumJ five is ah a&ione<br />

&heris, aut Acris, Mediive cujufcunque i%u corporci feu ineorpo..<br />

rei oriatur corpora innatxntia in fc invicem utcurlqlrc im~~knti~,<br />

Eodcm ficnfu generaliwulinrpo VQCC~ Impulfus, nun f’ccies viriuw<br />

&


~RoFOSITIO XXIV. THEOREMA<br />

Nam VeIocitas, quam data vis in data mat&a dato tempore ge.<br />

-herare potefi, efi UC vis & cempw~ *dire&t-q 8~ maceria inverk. QUO<br />

majo,, efi vis vel ma@3 ternpus vel minor materia, e0 major genew<br />

~rabitnr velocitas. Id quod per mows Legem fecundam manif=<br />

fium efi. Jam vero fi Pendula ejufdem fine longitudinis, viresmo.<br />

r&es in locis a perpendiculo z.quaIiter diftantibus fiunt ut pan&,.<br />

ra : ideoque ii corpora duo ohllando defcribant arcus aqua& &<br />

arcus iili dividantur in parres aquaIes; cum tempera quibus car-<br />

:gora ,defiribant hgulas arcuum partes correfpondenws ht ut<br />

.tempora ofcillationum tothum 9 erunt velocitates ad invicem in<br />

correfpondentibus ofcillationum partibw UC vircs matrices & tota<br />

ofcillationum tempera, dir&e & quantitates materix reciproce:<br />

adeoque quantitates materia ut vires & oicillationum tempora dire&e<br />

& velocitates reciproce. Sed velocitates rcciprwe fint ut’<br />

tempera, atque adeo tempora dire&e & velocitatcs rc-ciproce lunt<br />

ut quadrata remporum, & propterea quantitatcs materix iilnt ut<br />

vires matrices & qwldrata temparum, id efi, ut pondcra & quadrae<br />

%a temporum, ,$&E. 2).<br />

GvvZ. I. Ideoque G aempora filnt xqualia, quantitates mater&<br />

dn Gngulis corporibus erunt ut pondera.<br />

Coral. 2. Si pondera funt zqualia, quantitates mareriz crunt ut<br />

quadrata temporum.<br />

CoroL 3# Si quantitates materiz xquantur, pondera erunt rcciproce<br />

ut quadrata Item,porum,<br />

CoroL


C I P I A M A T H E M AT r c A,;.. .I-~‘~;<br />

& qualitates Phyflcas9 tied quantitares SC proportiones Mathema- LIO ER”<br />

ticas in hoc TraLtatu expendens, Ut in Dcfinitionibus cxplicui. In rR1blUs.<br />

Matheli inveCi!igandz fimt viriwin Quantitates St: rationcs illat, qu.c<br />

ex condirionibus quibufiunque pofitis confkquentur : deinde, ubi<br />

in Phyficam defienditur ) conferendz ht h rationes cum FIXnomenis,<br />

ut innotefcat quaznam virium conditiones hgufis barporum<br />

attra&ivorum gcneribus competant. Et turn demum deyi-a<br />

rium fpeciebus, caufis & rationibus Phyficis rutius difputare hebit,<br />

Videamus igitur quibus viribus corpora Spkmrica, ex particulis<br />

modo jam expofito attraQivis confiantia, debeant in k mutuo.<br />

agere, 8c quales. motes inde confequanrur..<br />

.’ ‘,<br />

1<br />

3<br />

Sit HIKL fiper’ficies illa Sphzrica,<br />

&T corpufculum intus conftituturn.<br />

Per T agantur ad hanc filperficiem<br />

liners dux HK, IL, arcus<br />

quam l+nimos Ef.f, KL intercipientes.;<br />

&, bb triangula. HI, 13 .L T M<br />

(per Coral. 3, Lem, VII) iiinilia, arcus<br />

illi erunt diitantiis HT, LT profiortionaks<br />

; & Cuperficiei Spharicz<br />

particulz quavis ad HI Sr LKL, rettis,$er<br />

pun&urn .T tranfeuntibus undique<br />

term&t%, etunt in duplicata<br />

illa ratione. Ergo vires harum particularurn in corpus,T exercitx<br />

fint inter fe acjuales. Sunt enim ut particular diretie &’ quad&a<br />

difiantiarum in$erk. Et .hx dux rationes componunt rationem<br />

xquali-


P$g PHIL6’SOP ~~ NATURAL<br />

I) I! M c) 32qualitatis. Attra&ioncs igitur, in cantrarias pnrtes xcfualiter fat-<br />

‘r 1~<br />

(1.: UKI’U ILL 51 LX, ii: mutuo deihunt. Et fimili argumento , attra&ioncs ornnes<br />

per tocam Spha32cank fiiperficiem a contrariis attratiionibus defiruuntur.<br />

Proinde corpus T nullafn in partcm his attraOknibus<br />

impellitur. & 23, 50.<br />

Sint A NK B, u h k b squalcs dux filperficics Sphxricz, ccntris<br />

J’, s, diamctris AB, nb defcriptz, TX ‘I>, p corpufcula lfitn extrinfetus<br />

in diani?Cris illis’ prbchifiis. Agdnruk a cbfpukulis lincx<br />

‘p @g-h 1p Y. & _.*‘-;%-“*--+\<br />

--“. .-,_--..*c+-<br />

,“I.‘,“^...<br />

*,..i


I<br />

verk Scd partziculs iiint ut Sphra, hoc efi, in ratione triplicata<br />

diametrorum, g diitantk funt ut diamecri, & ratio prior dire&<br />

una cum ratione pofieriore bis inverfe efi ratio diametri ad diametrum<br />

s E. ‘52.‘<br />

C’orol, I. Him ii corpukda in Circulis, circa Sphxras ex materia<br />

squalitcr atcra&va confiantes, revolvantur ; Gntque difiantix a centris<br />

Sphxmrum proportionales *.<br />

carundem diamecris: Tempora p&i-<br />

c&. 2. Et vice ver& ii Tempora periodica fint aqualia;<br />

difian& erunt proportionales diametris. Confiant hax duo per<br />

Gorol. 3. Prop. lv.<br />

~bro./, 3, Si ad Solidorum duorum quorumvis fimilium & *qua&-<br />

ter denforum pun&a fingula tendant vires xquales centripeta decrefccntcs<br />

in dupiicata ratione difiantiarum a pun&s: vires quibus<br />

corpufcula, ad Solida illa duo fimiliter fira, attrnhentur ab iifdem,<br />

erunc ad invicem ut diametri Solidorum.<br />

P’ROPOSITIO LXXIII. THEOREMA XXXIII.<br />

Si ud S@htw alicujus tiatd pun& fmguia tendunt dquales vires<br />

centripet@ decreJcentes b d@icata ratione diJar,ztiarmz a pun-<br />

8i.r: dice ql.doH corpz&tklm~ inm sphmzm con/i%wtwn irzttrd--<br />

bitw zli proportionali diJ!antis fud ub ip&s cerntro.<br />

In Sphazra AB CD, centro S dekripta,.<br />

locetur corpufculum P ; & centro eodem 8,<br />

intervallo S*p, concipe Spharam interiorem<br />

T E RF defcribi, Manifeitum efi, per Prop.<br />

LXX, quad Spharicx fiiperficies concentricaz<br />

ex quibusSphz:rarum di,fferentia JEB F<br />

componitur, attratiionibus per attraaiones<br />

contrarias deitru&is , nil agunt in corpus<br />

p, Refiat Eola attra&io Sphaxa interioris<br />

T E$&F, Et per Prop, LXXII~ hax eit ut<br />

difiantia T S. J?$ E. 23,<br />

.rl. .-<br />

.,<br />

Scholium.<br />

Superficies ex quibus folida componuntur, hit 1~061 tint @rc<br />

.MathemaciczJ .Gzd Orbes adeo .tenues UC eorum c~~~~I~tudo infiar<br />

nihili


PR~N~YDI[A MATHEMATICA.<br />

-II I<br />

nihili fit.5 nimirum ,Orbes evanekentes ex quibus SPhxra<br />

:d;iinao I .,. ..,<br />

c&fiat, ubi Orbium illorum numerus augetur & craficudo mir~ui- i’, f1<br />

tur in infinitum. Simihter per Pun&a, ex quibus lines, filperficic?<br />

& ,. folida componi dicuntur 9 intelligendz funt particultr: rrqu,~lc:<br />

anagnitudinis contemnendz,<br />

PROPQS‘ITIO LXXIV. THEOREhlA XXXI\,‘,<br />

Nam difiinguatur. Sphara in f’uperfrcies Sphrericas inr3umcrJj<br />

Concentricas) & ,attra&iones corpufculi a Gngulis fuPerf?cicbus<br />

oriunda: erun t reciproce proportionales quadra to diIta uri:r carpukuli<br />

a centro, per Prop. LXXI. Et componendo, fxer fumma<br />

attra@ionurn, hoc efi attra&io corpufctzli in Sphxram totam, in<br />

eadem ratione. $$.p.m.<br />

0roZ. I. Hint in zqualibus difiantiis a centris homogenearum<br />

Sphzzrarum, attra&iones funt ut SphzrX. Nam per Prop, LX~LI,<br />

fi diitantiz funt proportionales diametris Sphzraruml vires crunt<br />

ut diametri. Minuatur difiantia major in illa ratione; &, difiantiis<br />

jam faEtis aqualibus, augebitur attra&io in duplicata illa ratione,<br />

adeoque crit ad attraRionem alteram in triplicata llla ratione,<br />

hoc efi, in ratione Spiiararuni.<br />

CoroZ, 2, In diitantiis quibufvis attraeiones fimt’ut Sphzrz apphcatae<br />

ad quadrata difiantiarum.<br />

Coral, 3. Si corpukulum, extra Sphzram homogeneam poficunl)<br />

trahitur vi reciproce proportionali quadrato difiantizc iku ab ipfius<br />

centro, confiet autem Sphara,ex particulis attratiivis j dccrefcet vis<br />

particu]a: cujuf’que in duplicata ratioqe difial3tra a parclcula.<br />

’ I. ;:-R~,~OSITIO LXXV. ,jiI3kREMA XXX-V.<br />

$i ;;dd L~@$~r~ d& p~nFFp jk$$a tendant wires sqlia?es tcvt~ipep&,’<br />

de,-$$centes ia &+&at~ ratione rdi&+~tiar~m d ~IW%$ j &CO<br />

gtiod spbarh ~UQC&S &a Jim&&s ah eadem attrahitw vi re&<br />

.<br />

proce propo~t~onali quadrato dzJ!antia- C~M~OWPA<br />

Nan~ iarticulz cujnfvis attra&io efi reciproce ut: quadrature di-


11-i. nroTu terea eadem efi ac fi vis tota attrahens manaret de corpufculo uni-’<br />

Conronua’ co ho in centro hujus Sphzrz H&c autem attraQi0 tanta eff<br />

quanta foret viciflim attra&io corpuf’culi ejufdem, fi modo iilud a<br />

fingulis Sphazrrt: attra&z particulis eadem vi traheretur qua.ipfis<br />

atrrahit. Foret autem illa corpukuli attra&io (per Prop. LXXIV)<br />

reciproce proportionalis quadrato difiantie fi13: a centro Sphzeadeoque<br />

huic fcqualis attraeio Sphzerz eit in eadem ratio-<br />

:; &i&E. 2).<br />

@awl. I. AttraEtiones Spha%wu-n, verfis alias Sphzras homogeneas,<br />

ii~nt: ut Sphgra: trahentes applicatz ad quadrtira-difiantiarum<br />

centrorum fuorum a centris earum quas attrahunt.<br />

Cool. 2, Idem vaIet ubi Stjhazra attratia etiam atmhit. Namque<br />

hujus puntia fingula trahene iingula alterius, eadem vi qua ab<br />

.ipfis viciflim trahantur 3 adeoquc cum in omni attra6tion.e urgeacur<br />

(per Legem IIT> tam punch-urn attrahens> quam pun&urn at4<br />

kra&um, geminabitur vis attra&ionis fnutuaz, confervatis prapdrrionibus,<br />

Curd 3, Eadem omnia, qw fuperius’ de ri>otu. corporum circa<br />

umbilicum Conicarum Se&ionum d’emonfirata funt, obtinent ubi<br />

Sphazra attrahens locatur in umbilico & corpora rnoventur extra<br />

Sphazram.<br />

Coral. 4. Ea vero qu3e de motu corporum circa c,entrum Conicarum<br />

Se&tionum demanfirantur, obtinent ubi m.orua peraguntun<br />

lntra Sphwam.<br />

PROPOSITIO LXXVf. THEOREMA XXXVP.<br />

Sunto,Sphazraz quotcunque concentric;p fnnifares A:B, OD;.EF,<br />

&c, quarum. interiores add& exterior&us componak mat&iam<br />

denfiorem


PRINCIPIA MAT’HEhiATICA. ‘E‘Is,<br />

denfiorem verfus centrum, vel fiubdu&a relinquant tenuiorem; &<br />

ha! (per Prop. LXXV) trahent Sphzras alias quotcunque concentri- ~~:~~~~<br />

cas fimilares G H, Id{, L; M, &CC. fingulre Gngulas, viribus reciproce<br />

proportionalibus quadrato diitnntiz SP. Et componendo<br />

vel dividendo, fiumma virium illarum omnium, vel excefis aliquarum<br />

fupra alias, hoc efi, vis quas Sphara toca ex concentricis<br />

quibufcunque vel concentricarum differentiis compofita A&<br />

trahit totam ex concentricis quibukunque vel concentricarum differentiis<br />

compoiitam G H, erit in eadem ratione. Augeatur numerus<br />

Sphazrarum concentricarwm in infinitum fit, ut maceriz denfitas<br />

upa cum vi aCtra&iva, in progreffu a circumferentia ad cen-<br />

&rum, kcundum Legem quamcunque crefcac vel decrekat : &, ad-<br />

dita materia ?on attra&iva, compfeatur ubivis denfitas deficiens, eo<br />

UC Spharz acquirant formam quamvis optatam 3 & vis ,qua harum<br />

plna attrahet alteram erit etiamnum (per argumenturn .fiperius) in<br />

eadem ilIa difiantia: quadratz ratione inverti. &EL 23.<br />

,’<br />

CiwoZ, I. Hint ii ejufmodi Sphars comp!_ures, fibi invicem per<br />

omnia fimiles, fe mutuo Xrahant j gtra&on&3~acceleratrices fingularum<br />

in fingulas eruntJ in aqualihws quibufiis centrorum diRanti&<br />

ut Spharz attrahentes.<br />

CoroZ. 2, Inque diftantiis quibuCvis inzquaIibus, ut Sphaxaz attraentes<br />

applicatz ad quadrara difiantiarum inter cenrra.<br />

Cb&f. 3. AttraEEiones vero matrices, feu pondera Sphararum in<br />

Sphzras erune, in zqualibus centrorum difiantiis, ut Sphxr;r: attrahentes<br />

& attra&ta conjun&im, id efi, ut conten,ta fub Sphazris per<br />

multiplicationem produ&a.<br />

CO&. 4, Inque dif+antiis inzqualibw, . ut cotltenta illa applica,ta<br />

, ad quadrata difiantiarum inter centra.<br />

.<br />

Aaz ” COTOZV


IS0 PHIL@SOPHI& NATURAf,Is<br />

,<br />

II:: >IIlJ~T u Cowl. 5, Eadem valent ubi attra&io oritur a Sphzer;r: utriufqu?<br />

I I’,! 1’ c, I? u ?.I virtute artraaiva, mutuo csercita in Spkram alterntn. Nat-u viribus<br />

ambabus gcminntur atcra&io, proportione krvak<br />

Cornl. 6. §I hujufinodi Sph3zrfE aliqw circa alias quiefkntes revolvantur,<br />

fingullt circa fingulas, fiatyue-difiantk inter centra revolvcncium<br />

& quietkntium proportio&les quiekentium diamc:<br />

‘.,.<br />

tris; aqualia clrunt Tempera periodica. a<br />

Curol. 7. Et viciflitn, fi Tempera periodica funt klualia’; .ditianriz<br />

erunt proportionales diametris. II,<br />

CoroZ. 8. Eadem omnia, qu3: fuperius de motu corporum, c&a<br />

umbiJicos Conicarum Seaionum demo&rata fi.mt, obcinent ‘u’bi<br />

Sphzra attrahens, form=:& condit;anis.,cujur~is jam,detiripts;:lo:<br />

catur in umbilico.<br />

CaroLg. Ur 8z ubi gyrantia funt etiam Sphxrz artrtihentes, ~011..<br />

ditionis cujufvis jam defcriptz<br />

FROPOSSTIO LXXVII. THEORkMkXXXVIr.<br />

Si ad&gdI S’h~rartim pun8d tendant +res centr$etie,proporsPionales<br />

d$antiis pm&form a corporibzts attrah : &CO quark<br />

vi8 compoJta, qua Sphw t&u Je n2autivo Pabent, e-0 fit dim<br />

Jhmdiu inter centra Sphmwm.<br />

,Cag. 1;. Sir ;4EBF Sph&r?, ,,&’<br />

centrum:e&&:T corpufcQlurrl atop :<br />

trati:u&, TA~SB axis SpI&ra: p&r<br />

centrum corpufculirranfiens,. E F;.<br />

.-<br />

&i Avis centripeta, in corpufculum T,fecundtirn lineam T H exere<br />

cita, eft ue diftancia T H; & (per Legup Corol. 2:) fecundurn Ii7<br />

neam T G, i*eir verfus centfum S, ut longittido TG. lgirur’ pun:<br />

Qortim.6ninium in .plano E Fj: flOC efi pla,ni ,tdtius vi$ qua co+,&<br />

culum T trahitur verfus ceqtrum S,, e@ ut numerus pug&oruti<br />

&I&US in ditian-tiam T G : ;id efi, ut cofitefitum fib plano,ipfo’ EF<br />

& difiantia illa 5? G. Et Gmiker vis plani e%, quai corptifculum T<br />

.; .<br />

trahitur


trahitur verfm centrum $,efi UC planum illud dukm in difiantiam ~11) pi R<br />

f&m Tg, five ut huic ,rquale planum EFB duQum in difianriam 1’11r21Pici<br />

illam Tg; & knma virium plani utriufque w planum E F ducturn<br />

in filmmam difiantiarum T G +Pg, id e$ ut planurn illud<br />

&Bum in duplam centri St cor.pufculi difiantiam T S; hoc e&, UC<br />

duplum planum E F duQum jn difianciam TS, vel ut fimma ;equ’alium<br />

planorum E F’+ef’ du&a in dlfiantiam eandem. Et fiitiili<br />

irgumenta , vircs omniunl:planorum in Sphazra tota, hirlc inde<br />

zqkaliter a centro Sphrera difiantium, fiJIIt ut fiJf'J3IIIa ph'orulla<br />

duQa in difiantiam T S, hoc efi, ut Sphza tota duBa in diffantiam<br />

centri fui S a corpufculo 73. 2&E;. ‘D.<br />

.6&s. 2. Tr&ar jam corpufculum ‘P Sphkwam AE B F. Et eodem<br />

argutiento probabitur quad vis, qua Sphara illa trahitur, erit.><br />

yt difiantia T S.. 2&E. ‘D.<br />

1 -Cm. ,, 3,.,, Coti’pbnacur :jzim Sphazra altera ex corpufculis innume-<br />

,-fsy’T j &’ quo@$ Vi’& qua corpukulum unumquodyue trahitur;<br />

efi-ut difiantia corpufculi a centro SphrLt: primz duAa,in Sphzrain<br />

eatidcm, ‘atque adeo eadem efi ac fi prodiret rota de corpug<br />

culo unico in centro Sph;urX; vis tota qua corpufcula ornnia in<br />

Sphrera fecunda trahuntur, hoc e$ qua Sphzra illa tota trahitur,<br />

eadem erit ac ii Sphara illa traheretur vi prodeunte de corpufculo<br />

unico in .centro Spharz pr?maz, & propterea proportionalis efi ~di-<br />

eric vis ex utraquk compofita ut di$e-.<br />

rentia contentorum,: hoc efi, .ut Cumma zqualium planorum d.uQa<br />

in femiffem diff’erencia: diitantiarum, id efi, ut fumma illa du&.iiir<br />

p $’ difiantiam corpufculi a cenrro Spharz Et fimili argumcnto,<br />

attra&:io planorum omnium E F, ef in Sphzra tota, hoc efi, attra&io<br />

Sph,?zra tot& efi ut >fumma planorum omnium, k’cu, Sph,rra<br />

tota, dti&a in p S difiantiam corpufiuli a centro §pI!zrx. ,@ E.23,’<br />

ctis. 8: Et~fi”%x ~orpu~~ulis’,itlnum~~i~ t p. compqnatur Sphara<br />

davab G&a: SphFram pribrcm A E B F. iira I probabitw ,ut prius<br />

qupd atcra&io, *five * fimp$x Sphzrs umus in alteram,., $ve mu tua<br />

~tri$$ye;in fe iy&em,<br />

1<br />

erir: ut difian tia cenerkum p X &E. 52<br />

PRO=-<br />


Demonfiratur ex PropofItione przcedente, eodem mode quo<br />

Prvpofitio LXXVI ex Propofitione LXXV demonfirata fuit. ;<br />

Curd. Quzz fuperius in Propofitionibus x ‘& LXIV de mot&<br />

corporum circa centra Conicarum Se&ionum demonfira ta fint,,<br />

valenc ubi attra&iones omnes fiunt vi Corporum Sphzricorum<br />

conditionis jam defcriprz, funtque corpora attra&a Sphazrz condicionis<br />

ejufdem.<br />

AttraRionum Cafus duos infigniores jam dedi expofitos; n.friG<br />

rum ubi Vires centripetz decrefcunt in duplicata difiantiarum ra-<br />

Gone, vel crefcunt in dieantiarum ?atione Gmplici; efficientes<br />

in utroque Cafu ut corpora gyrentur in Conicis SeBionibus, &<br />

componentes corporum Sphaericorum Vires centripetas eadem Lege,<br />

in receffu a centro, decrefcentes vel crefcentis cum .feipfis: :Qod<br />

efi notatu dignum. Cafus czteros, qui con&fiones r&us ele~<br />

gantes exhibent , figillatim petcwrere longum e&t. Malim<br />

CLW~OS method0 generali Gnu1 camprehendere ac” determinarer<br />

3 t fkquitur.


84j. ??HILOSOPHI& NATURALIs<br />

u C :\lo T U Iineola illa rDd: at Cecundum lineam T S ad centrum S tendentem<br />

“~~~P~P.u:.~ minor, in ratione T 13 ad T E, adeoque Ut ‘2’23 ~93 d. Dividi<br />

jam intelligatur linea ‘D F in particulas innumeras aquales, qu3:<br />

iinguls nominentur I) B j & fuperficies FE dividetur in totidem<br />

xquales annulos, quorum vireserunt ut fumma omnium T 2) x Dd,<br />

hoc eif, ut t ‘T Fq - : T ZI q, adeoque ut 2) E qtid Ducatur<br />

jam fup&ficies FE in altitudinem Ff j & fiet folidi E FJe vis exercita<br />

in corpufculum T UC I) Eq x Ff: puta fi detur vis quam<br />

particula aliqua data Ff in diitantia T F exercet in corpukulum<br />

‘P. At ii vis illa non detur , free vis folidi E Ff e ut folidum<br />

c<br />

DE g x3” & vis illa non data conjun&im. &.& E. 2).<br />

PROI’OS1T10 LXXX. THEOREMA XL.<br />

Si da Sphtr~ di~lajti~ A B E, centro S dejcripw, pmticuh &y.-<br />

lm cequales teudant &qua/es zlires centripetd, & ud SpbLer~<br />

axem AB, in quo corpufduvn aliquod I? locatur, erigmtur de<br />

pan& j%zgulis D perpendiczdla D E, Sphere occwrentia ivy E,<br />

& in ip/Zs cupiantur lov@udivzes D N, ‘qurzp Jnt ut quantit&<br />

.DEgxPS<br />

-- & vis gtiam Sphav purti& &a in dxe ad di..<br />

PE<br />

Jzntidm P F, exercet h.z corpz$Am I? conj&&n : dice qgod<br />

Vis tota, qMa c0rp&&vn I! trdhitur 5wfis Sphm2m2, e0 u*,<br />

ared comprebenJ-.u jib axe Sph mg AB .& kneu curva A,NB,<br />

gzum pm&vvz N perpetuo tangit.<br />

Etknim


( per Prop. 6, Lib. 2. Eiem. )<br />

fur itaque 2 SL 1) - L;Z?q aquatur re&angulo AL B. Scribal<br />

- AL B pro 23 Eq; & quantitas<br />

I)Eq XFS<br />

T Er’ qua2 Gcundum Corollarium quartum Propofitionis<br />

.--<br />

Luh5%5-<br />

TExV =<br />

przecedentis efk ut longitudo ordinatim applicats ZJN. refolvet:<br />

lrefe in tres partes<br />

2SL-DxTS- LTDEq?vTS_A<br />

TExV<br />

x<br />

ubi fi pro V fkibatur ratio inverlra vis centripetx, &<br />

pro T J3 medium<br />

proportionale inter T S & 2 L I); tres ik p<br />

lartes evadent<br />

ordmarnn applicata linearurn totidem curvarum, qua<br />

rum area2 per<br />

Methodos vulgatas innotcfcunt, ,$&E. F.


Escempl. I. Si vis cerrrripeta ad fingulas Sphxrx particulas ten- PC+ I:< “J<br />

&XS fit reciproce ut dlfkantia; pro V fkribe difiantiam 2)&‘j dein<br />

ALB<br />

zTSxL2) pro TEq, & fret Di’V ut SL-~L~-m.<br />

L:BFk<br />

ALB<br />

Pane 9 N xqualem duplo ejus 2 SL - L D - m: & ordinatx<br />

pars data z SL du&a in longisudinem AB defkibet aream re&an-<br />

@am ZSLxABj & pars indefinita LD du&a normaliter in<br />

eandcm longitudinem per motum continuum, ea Iege ut inter movendurn<br />

crefcendo vel decrekendo aquctur femper longitudini<br />

L I), defcribet asearn LBq-L.Aq,idefi,aream SLXAB; qu,?:<br />

fubdulka de area %F; z 5’; x AB relinquit aream S L x A B.<br />

IPars autem tertia L CD duea itidem per motum localem normam<br />

liter in eandem longitudinem, defcribet 1<br />

aream Hyperbolicam j qua fubdu& de<br />

area 5’ L x A B relinquet aream quxfitam<br />

AB NJ?. Unde talis emergit Problematis<br />

confiru&io. Ad pun&a L, A, B<br />

erige perpendicula .LZ, Aa, Bb, quorum<br />

Aa ipfi LB, EL Bb ipfi CAxquetur.<br />

Afymptotis L 2; LB, per punka a, b defcribatur<br />

Hyperbola ab. Et a&a charda<br />

E7 a claudet aream a b a arex quefitx<br />

A B NA xqualem.<br />

E,xempZ. 2. Si vis centripeta ad fingulas Sphzrx particulas tendens<br />

fit reciproce ut cubus difiantix, vel (quod perinde efi) ut cubus<br />

T E cztb<br />

iIle applicatus ad planum quodvis datum; firibe<br />

2ASq pro v3<br />

SLxAS; ASq<br />

dein zT$xLa pro 13 Eq; 8~ fkt D N UtFEL-a--<br />

2 P s<br />

XAsq, w-m id efi (ob continue proportionales TS, AS, 5’1)<br />

LBXSI.<br />

Si ducantur hujus partes tres<br />

lab Z’D- +“s 2LI)q *<br />

LSP<br />

in longitudiaem A B a prima m generabit aream Hyper-


?7 F JIu r u<br />

c. c,x 1’ 011<br />

” E: bolicam ; fecunda % S I aream i A B x 5’1; tertia ALBxSIare<br />

2LCDq -<br />

ALBxSP ALBxSI<br />

am --i-L-J ---. - I 2 L B , id en ; AB xSL De prima f%b-<br />

ducatur fumma kcundx Sr: tertix, &<br />

manebit area quxfita AB N A, Un- 1 :d<br />

de talis emergit Problcmatis confiru- ;:<br />

Qio, Ad pun&a L, A, S, B erigc<br />

::<br />

‘.<br />

perpendicuIa L I, Aa, $1, Bh, quo-<br />

:. :<br />

rum Ss ipfi $1 ,rquetur, perque pun- ; . ..,.<br />

L3um s Afympcotis 1; Z, LB defcrid ; “s....,<br />

batur Hyperbola a s6 occurrens per- ; “‘.,..:r<br />

pendiculk An, B b in a Sr b 5 & re&- ; !““**L.<br />

....,.<br />

b ,.,._<br />

angulum 2 A S1’ fubdu~~um de area i ! i z<br />

Hyperbolica A as L B reliquet aream E A .I. ,$ ii<br />

qt.&tarn AR .NA.<br />

Exemtipl. 3. Si Vis centripeta 3 ad Gngulas Sphaxrz particulas<br />

tendens, decrekit in quadruplicata ratione difiantix a particuhs;<br />

fixibe *J%<br />

mALSIs pro V, dein Z?ffp~~<br />

pro 59 E, & fiet I) N ut<br />

SIqxSL, I J-J2 I SIpAL B<br />

d2SI<br />

2' L 2) c'<br />

- ~._- --<br />

2y.2SIX~gAP 21"2sI x4L+ci<br />

Cujus tres partes du&tx in Iongitudinem AB, producunt areas t&t-<br />

idem, viz.<br />

tSIqxSL;* I I Slq<br />

dzSI<br />

,SIqxA% B.<br />

qtI2i.u<br />

1/LA -- z/L&-&wLm-~‘LA;<br />

-.<br />

in ~ L iCsb - JL iCub. Et hx pofi debitam redu?<br />

&ionem fiunt Ha vero, fu 6,<br />

Qispofierioribus de priore, evadunt ” 7 L Ic21b I . Igitur vis tota, qua<br />

corpukulum T in Sphax32 centrum trahitur, ei7c- ut ‘$$-$,<br />

id e&<br />

reciproce ut. I-‘&’ cub x.T I. $ E. 6.<br />

Eadem Method0 determinari poteit AttraBio corpufbuli fitP.i*<br />

tra Sphzram, kd ex,peditius per Theorema kquens. ‘,


cem ut S’*T qrlnd ad SA qlcdd: Si in quadruplicata, ut ST CZ& ad<br />

1)~ ?*fnT’J<br />

Cc?fQxC:*I S/g c#fts. Unde cum attraQio in T, in hoc ultimo c$k inventa<br />

fuit reciproce nt 9’ S cu6 x UF.I, attra&io in .l cric reciproce ut<br />

SAcrfL x PI, id efi (ob datum S A cub) reciproce UE 191. Et<br />

fimihs eR progreffus in infinitum. Theorema vero fit demon-<br />

If2ratur.<br />

Stantibus jam ante confiruQis, & exifiente corpore in loco<br />

quovis -T, ordinatim applicara D A? inventa fuit ut cz>Eg~TS<br />

T&XV *<br />

Ergo fi agatur IE, ordinata illa ad aliu,m ,quemvis locum 1, mu-<br />

tatis mutandis, evadet ut one vires centripetas, e<br />

Sphzr~ pun&o quovis E manantes, effe ad invicem in difiantiiq<br />

-d,E, TE, ut TEE ad IE”, (ubi numerus. G defignet indicem<br />

DEqxTS<br />

yotefiatum TE 8r IE) & ordinat? ilk fient ut TExTED &<br />

-- ZlEijXIS -.- J quarum ratio ad invicem efi ut T 5’x IE x 123 n ad<br />

IExIE”<br />

IS~TEXTE’J. Q. uoniam ob iimilia triangula STE, SE& fit<br />

dE ad T ,?3 ut IS ad SE vel SAj pro ratione IE ad T E fcribe<br />

rationem IS ad SA; & ordinatarum ratio evadet T SX IEn ad<br />

.SAxT En. Sed T S ad SA iilbduplicata efi ratio difiantiarum<br />

T S, Slj & I E n ad T E n fubduplicata efi ratio virium in difiantiis<br />

T S, IS. Ergo ordinate, & propterea area quas ordinate<br />

defcribunt, hifque proportionales. attra@iones, funt in ratione com-<br />

.pofita ex fubduplicatis inis rationibus. $Z& E, 9.<br />

PRO POSIT10 LXXXIII. PROBLEMA XLIr.<br />

Sit T cot us in centro Sphazraz, Sr R BSfZ> Segmenturn ejus<br />

piano A 13 B & fu erficie Sphzrica RRBS contenturn, Superfitie<br />

Sphazrica E: F Gp centro T defiripta kcetur ‘D B in F, ac zliq<br />

fiinguatur Segmentum in partes B R E F G S, FE I) G. Sir:<br />

autem Cuperficies illa non pure Mathematics, fkd Phyfica, pro-<br />

$imditatem habens guam minimam. Nominetur ifia profundi;<br />

,tas Q


PRINCHWk WlA’T~HE’MA~T‘IC’A, nyn<br />

tas 0, & erit hat fitiperficies (per de- LID&A<br />

monfirata Archimedis) ut ft;! Fx Z, FxO. r R I N IJ 8.<br />

Ponamus praterea vires attra&:ivas particularum<br />

Spharz effe reciproce ut<br />

diftantiarum dignitas illa cujus Index<br />

efi rz; & vis qua fuperficies FE trahit<br />

corpus “P crit ut 23F.x 0 0<br />

‘Pj?i~- I*<br />

Huic pro- $<br />

portionale fit perpendiculum F;N ductum<br />

in 0 j & area curvilinea 239 L IB,<br />

quam ordinatim applicata FN in longitudinem<br />

Z)B per motum conrinuum<br />

du&a defcribtt,, erit ut vis tota qua<br />

Segtiencum totuny RB SD trahjt corpus fp. g E. 1.<br />

PROPOSITIO~LXX-XIV. PROBLEMA XLUI.<br />

Imvenire wim qud corpufl-uhn, extra centrum Sphmie in axe Seg<br />

mentt cujuj&~ locaturn, attrahitur ab eodem Segmento.<br />

A Segment0 E BK trahatur corpus 5!’ (Vidc Fig, Prop. LXXIX~<br />

LXXX, LXXXI) in ejus axe AD B locatum. Centro T intervallo<br />

T E defcribatur fiperficies Sphzrica EFK, qua difiinguatur<br />

Segmentum in partes duas E BKF&E FKD. Qzratur vis partis<br />

prioris per Prop. LXXXI, & vis partis pofierioris per Prop.<br />

LXXXIIl j SE fumma virium erit vis Segmenri totius E B K 2>.<br />

& E. I.<br />

Scldium.~<br />

Explkatis attra&ionibus corporum Sphzricorum, jam pergere.<br />

liceret ad Leges attraaionum aliorum quorundam ex -particulis attraQivis<br />

fimilitcr confiantium corporum j fed iita particnlatim<br />

tra&are minus ad infiitutum fpe&at. SufTecerit Propofitiones<br />

quafdam generaliores de viribus hujufmodi corporum, deque mo-<br />

.tibus inde oriundis, ob earum in rebus Philofophicis aliqualem<br />

ufum, fiubjungere.


PROPOSITIO LXXXV. THEOREMA XLII.,<br />

Iyam ii vires decrekunt in raeione duphcata diitantiarum a partieulis;<br />

attratiio verfus corpus Sphaericum, propterea quad (per<br />

Prop. ~xxrv) fit reciproce ut quadratum difianciz attra&i corporis<br />

a centro Sphzrz, haud G&biker augebitur ex ionta&u j atque<br />

adhuc minus augebirur ex conta&u, fi attraeio in receffi Corporis<br />

attraai decrekat in ratione minore. Patet igitur Propofitio de<br />

Sphzris attrafiivis. Et par eR ratio Orbium Sphzicorum concavorum<br />

corpora externa trahentium. Et multo magis res confiat in<br />

Orbibus corpora interius conftituta trahentihus, cum attraeiones<br />

pa&n per Orbium cavisates ab attra’tiionibus contra& (per Prop.<br />

LXX) tolfantur, ideoque vel in ipfo conta&u nulls fint. C&od<br />

fi Sphzris hike Orbibufque Spharicis partes quazlibet a loco contaftus<br />

remote auferantur, & partes now ubivis addantur : mutari<br />

ponunt figurx horum corporum attraaivorum pro lubitu, neo<br />

ramen partes additz vel fubdu&z, cum fine a loco conta&,us re-<br />

~mots, augebutit nosabiliter attra&ionis exceffim qui ex contaQu<br />

oritur. Confiat igrtur Propofitio de corporib.us Figurarug on+<br />

nium, $$Jz. I),


PaINCIJ?I.A MATWEMATPCA. a93<br />

PROPOSITIO LXXWI, THEOREMA XLIII.<br />

P B 1 ?.I! L<br />

Si particula fvm, ex quibti corpus attra&um componitw, zrires<br />

in receJ% corporis attra,% decreJknt i~ tr@icata ve! $ti[qyLaw.<br />

~~r@cata ratione d$antiarum a partictilis : Lattra@io fonge *fortior<br />

erit in contakb.4, q5mn cum attrahens 67 attrali%nz ititerzlallo<br />

zlel minim0 feparanttir ab invicem.<br />

Nam attraeionem in acceffu attraQi corpufctili ad hujurnlodi<br />

Spharam trahentem augeri in infinitum, confiac per Colutionem Problematis<br />

XLI~ in Exemplo f&undo ac tertio exhibitam. Idem, per<br />

Exempla /illa & Theorema XLI inter k collata 3 facile colligitur<br />

de attraQionibus corporum verfus Orbes concave-convexos, five<br />

corpora attra&ta collocentur extra Orbes, five intra in eorum cavitatibus,<br />

Sed & addend0 vel auferendo his Spharis 8~ Orbibus ubivis<br />

extra locum contnaus materiam quamlibet attratiivam, eo ut<br />

corpora attraRiva induant figuram quamvis afflgnatam, confiabit<br />

Propofitio de corporibus univerfis, 2& El 59.<br />

PROPOSITIO LXXXVII. THEOREMA XLIV.<br />

$i corpora duo Jabi invicem Jwilia, & ex materia qualiter attra-<br />

&va corc/?arrthz, JeorJm attrahaazt CorptiJcda Jb; ipJs proportional&z<br />

& ad se fimiliter pojza : attra%ones acceleratrices corp2&d0rti~<br />

in corpora tota erunt tit ut.truEio~~es acceleratrices<br />

corpu.culorulrz in eorum pa&Au toti proportionales & in totis<br />

JmZIiter poJs; tm~<br />

Nam ii corpora difiinguantur in particulas, qua: fint totis proportionales<br />

8s in totis fimiliter fit32 ; erit, ut attraRi0 in particulam<br />

quamlibet unius corporis ad attraeionem in particulam correfpondentem<br />

in corpore akero, ita attraaiones in particulas fingulas<br />

primi corporis ad attratiiones in alterius particulas fingulas correfk<br />

pondentes; & componendoS ita attraQio in totum primum cor,pus<br />

ad attraaionem in totum fecundum. $& E. 13.<br />

C’oraZ, I. Ergo ii vires attraRiva particularurn, augendo &Ran-<br />

*ias cor.pufculorum attra&orum 3 decrekan’t in ratione dignitatis<br />

CC<br />

cujufvis


194<br />

p~l[~~S6PHZ~ Nt9SCuRaEl[S<br />

ar ,11,,~17 cujufvis diitantiarum: attra&tioneS acceleratrices in c0rpora tota<br />

CoRI’011u:f crunt ut corpora dire&e & difiantiarum dignitates ilk inverfe,’ Ut<br />

c vires articularum &m&cant in ratione duplicata difiantiarum<br />

fl coypu P culis atcraks ’ , corpora autem fint I.lt A Cub. & i? CR&. adeoque<br />

rum corporum latera cubica, tunl. corpufcu!orum att.ra@ofLlnl<br />

diitanti;z a corporibus, ut kf & B: atCra&.iones accekratri-<br />

A cub. B sub.<br />

ces in corpora erunt UC id efi, ut cor+orum la-<br />

Z+. 8c B quads<br />

tera illa cubica A SC B. Si vires particularurn decrcfcant in ‘rarione<br />

triplicata dihntiarum a corpufcuiis atrraQis j arcra&iopes<br />

Acub. Bcub. .<br />

acceler2triceS in corpora tota erunt ut - 8~ Bczlba Id e ff> zqua-<br />

Lfcub.<br />

les. Si vires decrefcant in ratione quadruplicata: akratiiones in<br />

Acub. & Bed. .<br />

corpora erunc UT - -Id efit:, reciproce ut lagera cubi-<br />

44+ Jfwb<br />

ca A’ & ~3. Et fit in czteris.<br />

C’orok. z. Unde viciUim, ex viribus quibus corpora fimilia tia..<br />

hunt corpui‘cula ad fe fimilitcr p&a, colligi pot& ratio decrymenti<br />

virium particularurn attra&ivarum in receh corpuf&]i at-<br />

CraBi; G mode decrementurn illud fit dire&e vel inverre in ratiolIe<br />

Aqua difhntiarum,<br />

PROPOSITZO LXXXVIII. THI$OREM~A xLV&‘.<br />

Corporis A ST’Yparticulaz A,<br />

B trahanr corpufiulum aliquod<br />

Z vi$xxi quaz> ii particula 33<br />

quantur inter fe, fint u-t d&antiz<br />

AZ, B 2; fin particula fiatuan<br />

tur inazquales, fin t u t ha particulx<br />

in difiantkk fu+ A,Z, BZ<br />

refpeQive du&z. EC e$,po&k<br />

tur hze vires per contenta .illa<br />

AxAZ&BxBZ.JungaturAB,<br />

& kcetur ea in&! IG. fit AG ad B G ut particula B ad particuhm A’<br />

&


or: erit G commune cent-rum gravitatis particularurn A & B. Vis ~[i; E K<br />

AxA%(perLegum Coral, 2.) reioivitur inviresAXGZ&AXAG PplbI”s-<br />

&visBxBZinviresBxG%&B~BG.<br />

ViresautemRxAG<br />

& B x B G, ob proportionales A ad B & B G ad A G, xqualjrnr i<br />

adeoque cum dirigantur in partes contrarias, fk mutuo defiruunt.<br />

Reliant vires AX GZ & B x G Z. Tendunt ha ab Z verfus centrum<br />

G, & vim A -t-B x G Z componunt ; hoe efi, vim eandem ac<br />

fi ,particulz attraQivz A Sr: B confifierent in eorum communi gravitatis<br />

centro G, Globum ibi componentes.<br />

Eodem argumento, ii adjnngatur particula tertia C, & componatur<br />

hujus vis CI.IIII vi A+B x GZ tendente ad centrum Gj vis<br />

indeoriunda tendet ad commune centrum gravitatis Globi illius G<br />

& particular C; hoc efi, ad commune centrum gravitatis trium paroicularum<br />

A, I?, 6; & eadem erit ac ii Globus & particula C confifierent<br />

in centro illo communi, Globum majorem ibi componentes.<br />

Et fit pergitur in infinitum. Eadem efi igitur vis tota particularum<br />

omnium corporis cujukunque I? STY ac ii corpus illud, f&r*<br />

Vato gravitatis centro, figuram Globi indueret. $& E. D.<br />

CuroZ. Hint motus corporis attra&i 2 idem erit ac fi corpus<br />

attrahens R STY effet Sphaxicum: & propterea ii corpus illud<br />

attrahens vel quiefcat, vel progrediatur uniformiter in dire&rim 5<br />

corpus attra&um movebitur in Ellipfi centrum habente ifi att!ahentis<br />

centro gravitatis.<br />

PROPOSITIO LXXXIX. THEOREMA,XLVi.<br />

$i Corpora J;nt phru ex pdrticdis agutilibus con$kntiu, ~q~arum zriyes<br />

Junt ut d~&!hnti~ locorum a @g$h : vis ex ovmium vi&<br />

bzas cotipoJitlc, qud corpuJcu1~~ qaadcunque trahitur, tendet ad<br />

trtibentiuw commune centrum grmitatis, & eadem erit UC jZ<br />

truhentin ilk, Jerwto gravitatis centro communi,~.coirent & in<br />

.<br />

Glo bum formareln”ur.<br />

Demonftratur eodem mode, atquk Propofitio fiperior.<br />

Cord. ,Ergo motus corporis attrani idem erit ac fi Corpora trahentia,<br />

fervato communi gravitatis centro, coirent Sr: in Globum<br />

formarentur. Ideoque,fi corporpm trahentium commu+z g~+v!t~~<br />

tis centrum vel quiefiit, vel progreditur uniformiter in line3 k&a:<br />

coleus attra&um mqvebitur in Bllipfi , centrum habeate ;iti Cowtiuk<br />

illo trahentiuti xze;titro $pvitatis, ,,.a:..>:? ._I,<br />

cc 2 PRO;


si udJngu/a cjf~li ~clj~~~unque pun86 tendant 9ire.f cefftiale+f ces<br />

frlpeta, decye~&tes in quacunpe dijfantiarurn Wione : i?KW~<br />

nire vim qua ~o~pufculurn attrahitur ubiVis PoJtun2 ik reti%<br />

p+! plan0 circu/j ud centwm ejus perpendictilariter ir$j?k<br />

Centro A intervaIl quovis AD, in plan0 cui se&-a AT perpenchcularis<br />

efi, defcribi intelligatur Circulus j & invenienda fit vis<br />

qua corpufcnlum quodvis T ineundem attrabitur. A Circuli pun&to<br />

quovis E ad corpufculum attra&um T agatur r&a T E: In re.?<br />

8ta T A capiatur T F ipG T E Z- -3<br />

qualis, & erigatur normalis FK3<br />

quaz fit UC vis qua pun&m E trahit<br />

corpufculum T. Sitque IKL<br />

cwva linea quam puntium I(; perpetuo<br />

tangit. Occurrat eadem Circuli<br />

plan0 in 2;. In T A capiatur<br />

T H zqualis T 2>, & erigatur perpendiculum<br />

HI curve pradi& P -SF H<br />

occurrens in I; & erit corpuL A ii 2 i.<br />

i I f<br />

culi F attratiio in Circul‘um ut area<br />

;..‘.i..!.’<br />

!.. . a.....<br />

nlHlL duea in altitudinem AT.<br />

L***““‘k ;K”“’Ir<br />

Li& E. x.<br />

Etenim in AE capiatur linea quam minima Ee. Jungatur T e3<br />

8r in T E, T A capiantur T C, T.fipfi T e aequales, Et quoniam vis,<br />

qua annuli pun&urn quodvis E trahit, ad,.fe corpus T, ponirur effe.<br />

ut F,K, &.inde ais qua pun&um illud trahrt corpus T verfus A,~ efi ut,,<br />

AT ~2%<br />

TE<br />

, & vis qua annulus totus rrahit. corpus.T verfus A, ut.<br />

annulus & A’T *FK conjun&m ’ ‘* j annulus autem ifie efi ut retian-<br />

TE<br />

gulum fib radio LIE & latitudine E e, & hoc re&angulum (oh proportionalw.TE<br />

& A E, E e & CE] cequatur retiangulo 5? E.x,G’E<br />

feu. T E x Ffj .&it. vis qua annulus ifie trahit corps Q’?. v-erfii.s<br />

iA, ut: T E x,Ff & “;;F,K conjun&im, id eit, ut.contenrum<br />

.Ff<br />

x FKx.AT, five-ut are,a-F.&k$’ du,&a in A5?. Et, propterea<br />

hmma virium) cpibus annulpqnnq in .,Cir.c:culo.~ cpi cqxra A &,in-<br />

Ltervallck


Cylindrus fit, parallelogrammo<br />

A DE B circa axem A B revolure<br />

defkipcus, & vires cent&<br />

pet32 in hgula ejus punfla tendenres<br />

Gnt reciproce ut quadratri<br />

dittanriarum a pun&s: erir<br />

atcraAio corpufculi T in IIU~C<br />

Cylindrum uc AB-T E-j-T I).<br />

Nam ordinatim apphcata FK<br />

(per Coral. I. Prop. xc) erit ut 1<br />

gitudinem<br />

AB, defkribit aream<br />

TF<br />

- ‘y x, Hujus pars I duQainlon$<br />

I X AB j Sr pars altera-<br />

in longitudinem T B, defcribit aream I in ‘P E -AD id quad<br />

cx curvy L PI< quadratura facile oftendi pot&: ) & Mimi I iter pars<br />

eadem du&a in longitudinem T A defkibit aream I in ‘P fD - A 13,<br />

du&aque in ipfirum T 23, T A differentiam A B defcribit arearum<br />

dif?erentiam I in De content0 prim0 1 x AB auferatur<br />

contentum pofiremum .<br />

x in. & refiabit area L A B I<br />

zqualis I in AB - T E +T I). Ergo vis, -huic area: proportionalis,<br />

efi ut AB-TE-/-TD.<br />

visinnotekit qua Sphaerois<br />

A GB C?ZI attrahit<br />

corpus quodvis Tp, exteg&i<br />

in axe CUO AB iirum.<br />

Sit NKRMSeaio<br />

Conica cujus ordinatim<br />

applicata E Ii, ipfi<br />

T E perpendicularis, 3equetur<br />

fernper longitudini<br />

T 2), qua ducitur<br />

ad pun&urn illud 2), in<br />

quo applicata ifia Sphzroidem fecat A Spharoidis verticihus A, B<br />

ad ejus axem @ erigantur perpendicula AK, B M ipiis Ap, B I,<br />

zqualia refp’ee-rve, k propterea SeCcioni Conicz occurrentia in. K<br />

& isfj Sr jungatur KiW a,uferens ab eadenl fegmentujn KMR x,<br />

$is au&em Sph~~dis ccntruItP S & kmidiameter maxima 8.~: s& vis<br />

,,.


PRINCIDIA MATHEMATI~A; 1’93<br />

qua S$~rois trahit CorplIsT eritadvim q~d+h~r~, diametro AB Z,rBP.R<br />

ASx CJ’q - TSxl(‘MXI( P~Ib~~J*<br />

defcripta, trahit idem corpus, ut<br />

‘PLsq+CLYq-AS’q<br />

ad A$ cd<br />

3 bP J’quad’ Et eodem computandi fundamento invenire licet<br />

vires kgmentorum Sphzroidis.<br />

CO~OL 3. Qod Ifi corpukulum intra Spharoidem, in data quavis<br />

ejufdem diamerro, collocetur j attra&io erit ut iplius difiantia a<br />

centro, Id quad facilius colligetur hoc argumento. Sit A’G0.P<br />

Sphzrois attrahens, 6’ centrum ejus & I-’ corpus attra&um. Per<br />

corpus iIlud F agantur turn kmidiamcter SYA, turn r&3: duzz<br />

quawis 53 E, FG Sphzroidi kinc indc occurrentes in *L.J& E, F<br />

& G: Sintque 2> CM, k!‘L N fuperficies Sphzroidum duarum interiorum,<br />

exteriori fimilium & concentricarum, quarum prior tranfeat<br />

per corpus “P &c fecet re&as 23 E & FG in B & C, pofierior<br />

f&et eacdem re&as in H; I & .K, L. Habeant autem Spharoides.<br />

olnnesaxem communem, 8.z erunt reQarum<br />

partes hint inde interceptED *P ~1<br />

&:BE,FT&CG,2,4J-‘&&I,Fd~<br />

&, 4 G fibi mutuo azquales j propterea<br />

qubd reQz DE, T B St HI bifecantur<br />

in eodem pun&o, ut Sr re&z FG,<br />

p C k KL. Concipe jam I) I, F,<br />

E T G defignare Conos oppofitos, angulis<br />

verticalibus a> P F, g T G infinite<br />

parvis defcriptos, & lmeas etiam 1: E”<br />

fz1 H, E I infinite parvas effe ; & Conorum particuk Sphzroidum<br />

fuperficiebus abfcifl2 fD HK F, G L IEE, ob aqualitatem linearurn<br />

f~ H, ~1, erunt ad invicem ut quadrata difiantiarum fiuarum a<br />

corpufculo ‘Pi), & propterea corpufculum illud zqualiter erabent,<br />

Et pari ratione, c 1 ~uperficiebus Sphzrordum innumerarum fimikm<br />

concentricarum & axem communem habentium dividantur fpatia<br />

ye p $‘, E G C B in particulas, ha2 omnes utrinque aqualiter trabent<br />

corpus ‘p in partes contrarias. 2Equales igitur fimt vires .<br />

Coni 2) cp F & fegmenti Conici E GC B, & per contrarietatem fe<br />

lllutuo defiruunt. tit par efi ratio virium matcria omnis extra Sphazroidem<br />

intimam P CB AA Trahitur igitur corpus “P a fola Sphzroide<br />

intima T CB My & propterea (per COLON. $Prop. LXXTL) attraeio<br />

ejus ete ad vim, qua c0rpus.d trahlrur a Sphzroide tota<br />

A G Q B, ut difimtia 2’ S ad difiantlam .A&‘. & E. ‘D.<br />

PRO-


l‘,E<br />

h!OTLf<br />

CORFOROAI<br />

~RO~W$TI’iO XCII. PROBLEMA XLVI.<br />

Data Corpore attraGv0, iwenire rutionew decrementi &km ceni<br />

tripetarum in t$m pun&~ Jiizgula tendentiuw.<br />

E Corpore data formanda efi $phsra vel CyIindrus aliave figu-<br />

-ra regularis, cujus lex artrahonis , cuivis decrementi rationi con..<br />

gruens (per Prop. LXXX, LXXXI, ck XCI) iyvcniri potefk De+ fa-<br />

&tis experimentis invenienda efi vis attrahonis in diver& d&antiis,<br />

& lex attra&ionis in totum inde patefa&a dabit rationem decrementi<br />

virium partium fingularum, quam invenire oportuit.<br />

PROPOSIT XCIII. THEOREMA XLVXI, 2<br />

lrii solidurn ex wa purte planurn, ex reliquis autem paths injninm,<br />

conset -cx p~rticulis aqualibus #qualiter attrafh’vis, qtixrum<br />

zrires in recefti a solid0 decreJctint in ratione poteJatis cu-.<br />

jtiJwis dij!antiarum pluJguam quadratic&, & vi Solidi totim corptiJcuhm<br />

ad utramvis plani partem con$ttitum .trahatpr : dim<br />

guod Solid; vis iUa attrai%va, in recefu a6 ejw [tiperficie plaza,<br />

decreJcet in ratione potetatis, cy’zts lutus en! dzyantia corp$cz&<br />

u pfano, & Index ternario minor mam Index Zzotehkd<br />

s J<br />

?tis diJantidrtm.z.<br />

Cfzs. 1. Sit L G i! planum<br />

quo SoIidum terminatur.<br />

Jaceat Solidum autem ex<br />

parte plani hujus verfus<br />

I, inque plana innumera<br />

mHM,rcIN,&c. ipfiGL<br />

parallela recolvatur. Et<br />

prim0 collocetur corpus attra&kum<br />

C extra Solidurn.<br />

Agatur autem C G HI pla-<br />

06 illis innumeris perpendicularis, & decrefcant vires attraBiv=<br />

gun&orum Solidi in ratione potefiatis diltantiarum, cujus index fit<br />

zwlerus n ternario ,non minor* Ergo (per Coral, 3. Prop. xc)<br />

vis


1PFWWXPI.A MA~*HE~/~AT~c~. ‘2Oi<br />

vis qua planum quodvis OHM trahit pun&urn c elt- reciproce ut<br />

CH”-2. In plan0 m Hike capiatur longitude HMipfi C LIB-2 rcciproce<br />

proportionalis, & erit vis illa ut HM. Similiter in planis fin-<br />

@islG L,uIN, 0 x0,&c. capiantur longitudines GLJE,.KO,&c.<br />

ipiis CG%-2, Cdn-2, C.&L+2 38-x. reciproce proportionales ; & vi-<br />

JXS pIanorum eorundem erunt ut longitudines captaz, adeoque<br />

fumma virium ut fimma longitudinum, hoc efl-, vis Solidi totius UC<br />

area G.L 0 K in infinitum verfis 0 I< prod&a. Sed area ilIa (per<br />

notas quadraturarum methodos) efi reciproce ut CGs-3, & propterea<br />

vis Solidi totius et.I reciproce ut CGn-3. & E. 2).<br />

cas, 2. Collocetur jam cor,pukulum C cx parte plani IGL intra<br />

Solidurn, & capiatur difiantia CK xqualis difiantia CG. Et Solidi<br />

pars L GZoXO, planis parallelis IG L, a KO terminata, corpufiulum<br />

C in me&o fiturn nullam in partem traher, corltrariis op-.<br />

pofitorum pun&orum aAionibus k mutuo per zcqualitatem tollentibus.<br />

Proinde corpufculum C fola vi Solidi ultra planum OK fiti trahitur.<br />

Ha22 autem vis (per Cafum primum) efi reciproce us CK+3,<br />

I-IQC eR Cob azquales C G, CK) reciproce ut CG n-3. SE, 59.<br />

Go&. I. Hint ii Solidum L GIN plank duobus infiniris parallelis<br />

LG, IN utrinque terminetur j innotekit ejus vis attrafiiva,<br />

fibducendo de vi attrafiiva Solidi totius infiniri L G K 0<br />

vim attraQivam partis ulterioris NICO, in infinitum verfils KO<br />

prod&a.<br />

Coral. 2. Si Solidi hujus infiniti pars ulterior, .quando attra&io e-<br />

jus collata cum attra&ione partis citerioris nullius pene efI momen:<br />

xi, rejiciatur : attra&io partis illius citerioris augendo difiantiam de*<br />

crefcet quam proxime in ratione poteitatis CG@-3.<br />

C’oroZ. 3, Et hint fi corpus quodvis finitum & ex una parte pIanum<br />

trahat corpufhlum e regione medii illius plani, & difiantia<br />

inter corpufculum & planum collata cum dimenfionibus corporis<br />

attrahentis perexigua fit , co&et autem corpus attrahens ex<br />

particulis homogeneis 3 quarum vires attraaiva decrekunt in<br />

ratione potefiatis cujufvis plufquam quadruplicataz difiantiarum 5<br />

J7iS attrahiva corporis totius decrefcet quamproxime in ratione<br />

pot-fiat&, cujus latus fit difiantia .ill? perexigua, & Index ternario<br />

minor quam Index potefiatm pnom De cprpore ex particulis<br />

cohfiante, quarum vires attra&iva decrefcunt m ratione potefiatis<br />

triplicata difianfiarwm, affertio non valet; propterea quad, in hoc<br />

cafu, attraQio partis illius ulterioris corporis infiniti in Corollario<br />

fccundo, femper eR Tinfinite major quam attra&io partis citerioris.<br />

* ._.<br />

Dd<br />

i!k~0lila%


Si corpus aliquod perpendiculariter verfus planum datum tra;<br />

hatur, & ex data lege attraeionis qwratur motus corporis: Sol:<br />

vetur Problema quarendo (per Prop, XXXIX) motum corporis re&<br />

defcendentis ad hoc planum, & (per Legum Cowl. 2.) componendo<br />

moturn ilium cum uniformi motu, fkzundum Iineas eidem piano<br />

parallelas faaQ0. Et contra, ii quzratur Lex attra&ionis in planum<br />

~~~undurn lineas perpendiculares fa&a, ea conditione ut corpus attra&um<br />

in data quacunque curva linea moveatur, folvetur Problem<br />

ma operand0 ad exemplum Problematis tertii.<br />

Qperationes autem contrahi folent refolvendo ordinatinl applicatas<br />

in Series convergentes. Ut G ad bafem A in angulo quovis<br />

&to ordinatim applicetur longitude B, qua: fit ut bafis dignitas<br />

quaelibet AT ; & quzratur vis qua corpus, fecundurn -poEthem<br />

ordinatim apphcatz, vel in bafem attraeum vel a bafi fugatum,<br />

moveri p&it in curva linea quam ordinatim applicata term&<br />

no ho iilperiore lCempcr attingit: Suppono balm augeri parto<br />

m<br />

quam minima 0, & ordinatim applicatam mT’ refolvo in<br />

?.V---n<br />

m-2n<br />

,Qriem infilaitam A: +t 0 h” + mriamn 00 A x1 &. at-<br />

que hujus termino in quo 0 duarum efi dimentionum, id eR, tir-<br />

#.&mm-VW<br />

m-2n<br />

00,4-G-- vim proportionalem efk iilppono, E$<br />

zn?z<br />

igitur vis qwfita ut mm-mn A m?, vel quod perinde efi ,. ut<br />

?2?J<br />

mm-mfl m--in<br />

B fl’ Ut ii ordinatim applicata Parabolam attingat,,<br />

?aB<br />

exifiente m=z, & ar-I: fiet vis ut data qBO, adeoque dabi-.<br />

tur. Data igitur vi corpus movebitur in Parabol?,, queniaqmodum<br />

GRZ&WS demonfiravit. Qod B ordinatrm apphcz~&a<br />

Hyperbolam atdngat, exifiente m= o- I+,:.& TZ= I j fiei v$,ut<br />

a A-3 .feu 2B3: adeoque vi, qw fit ut cubus ordinatim ~pqhcatzel.<br />

corpus movebitur in Hyperbola. Sed miflis hujuiinodi Prop&&<br />

onibus, pergo ad alias quafdam de. MotuJ quas nondum attigi,


ROPOSI’I’IO XCW THEOREMA XLVIII.<br />

5’; Media duo Jmiluriu, spdtio planis parullelicr utrhque ter&ato,<br />

d@zgtiantur ab invicem, & corpus in tranJitu per hoc @atim<br />

attrahatur rue! impekmr perpendiculuriter QerSm Mediwz alter-<br />

24trm2, neque tifla alid vvi agitettir wcl impediatur : Sit uute~~<br />

,uttra&o, in dquulibus ab utroque plano dz$antiG ad eandem<br />

7ipfim parzem captis, ubique eddern : dice quod Jinus incidentiLc:<br />

erij ad J;mm emergentid ex piano Atero<br />

Case 1. Sunto Au, B b<br />

plana duo parallela. In+<br />

dat corpus in p)anum..prius<br />

Aa fecundurn lineam<br />

u<br />

d;H, ac totofuo per fpatium<br />

intermedium tranfitu<br />

attrahatur vel impellatur<br />

verfus Medium incidentiz,<br />

eaque aQioae defcribat<br />

lineam curvam H I3 &<br />

emergat jrecundum line- B<br />

am ~.I


204 PHILOSOPHIC fJA<br />

JJ E MOT U Cecans tam NM in T & L& quam MI produAam in Nj 8~ prima<br />

~~NPORUI.I fi attra&io vel impulfiis ponatur uniformis, erit (ex delnonitratis<br />

Gnlilai) curva HIParabola, cujus hzc elt proprieta% ut re&angulum<br />

fub dato latere reQo & lmea I M zquale fit HM quadrato ;<br />

fed g: linea NM bifecabitur in L Unde ii ad MI demlttatur<br />

perpendiculum L 0,. Z-<br />

quales erunc MO, 0 R i<br />

& additis zqualibus 0 x,<br />

01, fient totaz aquales A<br />

MN, IA. Proinde cum<br />

I R betur, datur eciam<br />

MN; eltque re&angulum<br />

NMI ad re&tangu-<br />

Pum fub latere re&ko 8~<br />

Iit& hoc eft, ad HMq,<br />

in data ratione. Sed re&<br />

angulum NMI aquak<br />

eit re&angulo T Ma jd<br />

eft, differentia quadratorum<br />

MLq, &TLq feu<br />

L Iq; & HMg datam<br />

rationem habet ad fui ipfius quartam partem ML; q : ergo datum<br />

ratio MLq - LI ad ML q, & divifim, ratio Llq ad ML g, 6~<br />

ratio dimidiata L 4 ad,/ML. Sed in omni triangulo L MA finus<br />

angulorum funt proportionales lateribus oppofitis. Ergo datur<br />

ratio finus anguli incident& L J4.R ad finurn anguli emergentiae<br />

UR, $?& ji$. Z?.<br />

62s. 2; TraMkat jam corpus fkcceEve per fpa’tia plura paltralk:.<br />

&is planis termina& Aa b B, B b CC> kc, & agitetur vi quaz fit in<br />

Gngulia


PRINCIIW!<br />

MATHEMATIcA,<br />

fingulis feparatim uniformis 3 at in diverfis diverfa 5 & per jam de- LIISER,<br />

monfirata, finus incidentk in planum primum Aa erit ad. finurn PRIMV~G.<br />

emergent& ex pla’no fecund0 B 6, in data ratione; & hit finus,<br />

qui efi finus incidentix in planum fecundurn 236, erit ad finurn<br />

emergentia.2 ex plan0 tertio Cc 3 in data ratione; & hit finus ad<br />

finurn emergentiz ex pIano quart0 D d, in data ratione; & fit in<br />

infinitum: &:$ex ;Equ.o> Gnus incident& in planum primum ad fi-<br />

1lun-r emergentk ex plano ultimo in data ratione. Minuan tur jam<br />

planorum intervalla & augeatur numerus in infinitum, eo ut afxra-<br />

Qionis vel impulfus aCtio, kcundum legem quamcunque afignatam,<br />

continua reddatur j & ratio Gnus incidentire in planum primum ad<br />

finurn emergentiz ex plano ultimo, femper data exifiens, etiarw<br />

num dabitus. $i$ E. D.<br />

PRO BOSI1[*10 X.CV. THEOREMA. XLIXe<br />

><br />

.@dem pojh ; dko qwod velocicq corporis antes incidevtiam efl<br />

c<br />

ud +YS cvelocitatem po.fT etiergkntaana, tit- Jnm~ emerge&g A<br />

,<br />

j%m incidentk<br />

. Ca@antur AH, Id zquales, 8-z erigantur perpenckik AG; ,dX<br />

occurrentia lineis incidentia: & emergent& GE, IR, in G & K:<br />

GH capiatur TN Equalis IK, & ad planum Aa demittatur<br />

rmaliter TV, Et (per Legum Corol. 2) difiinguatur motus cork<br />

poris in duos, unum planis Aa, B 6, Cc, 8~. perpendicularem, ali.<br />

. terum iifdem parallelurn. Vis attra&ionis vel impulfus, agen.do,fk<br />

cundum lineasperpendiculares, nil mutat,motum I’ecundum paralh+<br />

las, & propterea corpus hoc mot! conficret zqualibus temporibus,<br />

zqualia illa fecundum parallelas lntewalla, quz fint ,inter lineam<br />

AG & pun&urn H, interque pun&urn I& hneam dI


De hio;”<br />

tL 0 R I’ 0 1% U AI<br />

PRO’POSITIU<br />

XCVI.<br />

Nam concipe corpus inter parallela plana Ad, B & C.c, &c. defcribcre<br />

arcus Parabolicas, ut fupra 5 fintque arcus. illi ET, T ,$i$<br />

R&&C. Et fit ea linea: incidentia G H obliquitas ad planum p+rl?<br />

mum A&, ut finus incidentie fit ad radium circuli, cujus efi finus;<br />

in ea ratione quam habet idem finus incident& ad finurn emergentiaz<br />

ex piano I> d, in fpatium 2, de E: & ob finurn emergenzia<br />

jam fatinm zqualem radio, angulus emergentia: erit re&us, adeoque<br />

linea emergentiaz coincidet cum ulano 2) d, Perveniat carpus<br />

ad hoc planum in pun&o R j &‘quoniam linea emergentia<br />

caincidit. kim : eadem<br />

@ano, ,perfpicuum efi<br />

quod corpus non poteil:<br />

ultra pergere verfis<br />

planum Ee. Sed<br />

net potefi idem perge-<br />

&in ‘finea emergkntize<br />

Z&d, propteiea-quod<br />

perpecuo attrahitur vel irnpillitur .verCus Medium in&&&~. 3X&<br />

vertetur itaque inter plana Cc, CD d, defcribendo arcum’Y?arabola:<br />

*RR 2 cujus vertex principalis (juxta demo&rata G&k) efi in<br />

‘2 j 14 ecabit planurn Cc in e:odem atigulo,in 4, ac prius in & dein<br />

pergendo in arcubus parabolicis q& p.t5, kc. arcubus prioribus<br />

,RF, ‘,T H iimilibus & aquabbus, Gcabit reliqua plana in niaem<br />

angulis inp, h, kc. ac prius in T, H, 8-x. emergetque tandeni


~~rbui.m?~A MATHEMA


DE<br />

I\fOTU<br />

CQRPORUhI<br />

PROpOSIT XCVII. ROBLEMA XL<br />

6it A locus a quo corpufcula divergunt 5 B locus in quem con;<br />

-vergere debent j CD E curva linea qua circa axem AB revoluta<br />

defcribar fuperficiem qua&tam j 2), E curw illius pun&a duo qu%-<br />

vis j & E.& E G perpendicula in corporis vias AD, D B de&%.<br />

Accedat pun&urn I> ad pun&urn E j & line& 2) 5’ qua AI> au..<br />

:.getur, ad lineam 2) G qua I) B diminuitur, ratio ulcima erit eaden1<br />

~LWZ finus incident& ad hum emergentix. Datur ergo ratio<br />

+crementi line= AD ad decrementurn linea I) B ; & prop.terea<br />

5 in axe AB fimatur ubivis 1 pun&urn C, per quod curva CD J?S<br />

tranfire debet, & capiatur ipfius AC incrementum (2’2% ad ipfius<br />

B C decrementum C N in data illa ratione 5 centrifque A, BB 8~ iv-<br />

,tervallis AM, B AZ’ dekribantur circuli duo fk mutuo fecantes ln<br />

2) : pun&urn illud 2) tanget curvam quzfitam CD E, eandemque<br />

&vis tangendo determinabit. .&E. L<br />

~COVU‘): I, Faciendo autem.ut pun&urn A vel B nunc abeat in infinitum<br />

a nunc migret ad alteras partes pun&i ‘6, habebuntur Figuru<br />

ilk omnes quas Gzrtefws in Optica st Ceometria ad Refra-<br />

Qiones expofuit. Qyarum inventionem cum Carte~h maximi<br />

fecerit & fiudiok celaverit , vifim fuit hat ,propokotre $XP*<br />

m&To<br />

GwO~~


Carol. 2. Si corpus in fi~pcrficictn quamvis C D, fectrndum lineam r2 I ,$ w II<br />

reQam /f 23 lcgc quavis d&m incidcns, cmcrgal: Sccundum aliam .PR I~LU~;<br />

quamvis reElam ‘D IC:, / pi<br />

&: a pun&o C duci in- ..**<br />

...’<br />

...*<br />

tclligantur Linea= curv:I:<br />

..a-<br />

limper perpendiculnrcs :<br />

crunt incremcnta lineal<br />

rum ‘I> 59, $9, atqj Cdco<br />

linc3: ipfz F a, @J,<br />

incrementis iilis gcnitah<br />

ut fhus incidcntkc & c-<br />

mcrgcntkc ad inviccm :<br />

22 contra.<br />

PROPOSITIO XCVXII. PROBLEMA XLVIIX.<br />

Junea BB fkcet fugcrficiem primam in C & fecundtim in E,<br />

un&o 52 utc11nqt1e aff umpto. Et pofito Gnu incidentix in fiiperi:<br />

&em primam ad finurn emcrgcncin: cx e;ldcm, & Gnu cmcrgentiz<br />

6 fi~pcrficie fecunda ad hum incidenth in tandem 3 Tut quantitas<br />

ahqua dzttx M ad aliam datnm N ; roduc rum AB ad G ut fit B G<br />

ad Ck7 ut &I--N ad N, turn ACD a s 21 ut fit .&‘Hzqualis n G, turn<br />

etiam 2, F’ ad .K LN fit 22 IC: ad ‘D 11 ut N ad M. Junge KB, 81:<br />

cencro 52 intervallo 22 $1 dcfkribe circufum occurrcntem 1c.B pradu&z<br />

in zk, i fique 50 L parallclam age BE’: & pun@um 3 ranget<br />

Lineam P .5 Fj quz circa axcm AB rcvoluta defcrrbet ihpcrficiem<br />

quzfitam. $&E. E<br />

Nxm conci e Lincas CT, CRipfis AD, 99 F re$e@ivc, &I Lia<br />

ncas E+&!, E B ipfis FB, 3’2.3 ubique pcrpcndicularcs eKc, adeoque<br />

& crit (per Chrol. 2. Prt;lp. xcyrl)<br />

, adcoqucE;t ‘22 L ad ““33 K vel E B ad E K;<br />

&


DE bfOTU<br />

Conronusl<br />

@E -FS. Verum (ob<br />

proportionales B G ad<br />

CE & M-N ad N)<br />

efi etiam CE-+BE ad<br />

CE ut Mad N: adeoque<br />

divifim FR ad FS ut<br />

kf ad N, &propterea per<br />

Coral. 2. Prop. xcvIx,<br />

hperficies E Fcogit corpus,<br />

in ipfam fecundurn lineam F incidens, pergere in Iinea.<br />

ad locum B, &E. 23.


PROPOSITIO I. THEOlTJXA ‘I.<br />

Am cuti motu3 iingalis lemporis particulis aqudlibus hffis<br />

fir: ut VdciCita9j lioc dtj. ut itincris confe&i phrticula : erite<br />

componendo, motus toto tenipor’eamiffus ut iter totum. &&,!?.I).<br />

Go&, Igitur ii corpus, gravitate omni defiitutati, in fpatris liberisSola<br />

vi infita moveaturj ac detur turn motus totus fiib init& t.uti .<br />

etiati motus reliquwpofi fpatium aliquod confe&um : dabitur fjpatium<br />

totum quod c’orpus infinite tetipore defiribere pate,@. ,Erit<br />

,enim ffiat’ium illud a$ fpatium j&h defbriptuni, ut mobs t&w iub<br />

initio ad motus ilhs pa&h ariiiffani.<br />

,<br />

LEMMA I.


;1%% pj+mmx=v~~& NATwRALI.s<br />

UE MO-TLJ<br />

&=.ORPQRUM ROPOSITIO II. THEOREMA II.<br />

si corpori reJiJl’itur in ratione welocitatis, & idem [da vi i@a<br />

per n-sfed& pg&we ~o.mMhr,/inmmtur dutera tenzpora ay.u~<br />

{id : velo&&es in pinc$iis /i%gdOrclm tempOrum Ji4nt in progrefione<br />

Geometricti, & $atia j%~~liS te~~orjhs defcr+ta<br />

jiint ut zrelocitiate.f+<br />

J<br />

C~S, 1, Divid,atur ternpus in particulas 22qUaleS j & ii ipfis particularum<br />

initiis agat vis refifientix impulfo unico, CyLlX fit Ut VCIocitas:<br />

erit decrementurn velocitatis lingulis temporis patriculis ut<br />

eadem velocitas, Suns ergo vclocitatcs difFercntiis his proportianaks,<br />

132 proptePea (per LfX~- 1. Lib. 11,) contitzuc proportionales.<br />

Proil7de fi ex zquali particularurn numero componantur tcmpora<br />

qudibet zqualia ) erunt velocitates ipfis temporum initiis, ut fermini<br />

in progreflkme continua, qui,pcr Mtum capiuntur, omifl”o<br />

pa&n aquali terminorum intermedlorum numcro. i;‘omponuntuc<br />

autem horum terminorum rationes cx azqualibus ratronibus tern&<br />

norum intermediorum zqualiter repetitis, & pI+OptCrea hunt xquaks.<br />

lgitur velocitates, his eerminis proportionah, funt in progreff~one<br />

Geometrica. Minuarltur jam zquaks ilk temporum particuls,<br />

& augeatur earum numerus in infinitunh eo ut rcGfknti,7:<br />

impulfus reddatur continuus’; & velocitates in principiis aqualium<br />

6emporum, fernper continue proportionales, erllllt in hoc &am<br />

cai3 continue proportionales. S&E. 9.<br />

C&s. 2, Et divifim velocitatum diEercntizle, hoc yfi, carum pams<br />

fingulis temporibus arnifl”J=) fllCunt *UC tOti : Spat@ .auterrk fin@&<br />

temporibns dekciipta hnt Ut velocttatum artes amirE, (per Prop,*<br />

n.Lib. II.) St propterea etiam ut totz J G..E.fZ).<br />

Curot: Mint fi hfymptotis rctiaqylis AfB &; CN dcfiribxtur<br />

Hyperbola B G, Gntque AB, ED G. ad Afymptoton ~‘(2 per endicularcs,<br />

& exporlatur turn corporls velocltas turn refifientia il e3<br />

dii, ipfo Jnotwinitio, per lineam quamvis<br />

&tam AC, elapfo autem tempore aliquo<br />

pep linoam indefinitam ‘DC : ex,poni!<br />

potefi tempus per aream A B E.33; + fparium<br />

eo tempore dekriptum per hcam<br />

,&I>; Nam ii area illaS per motUm punbi<br />

D augeatur uniformitett admodum tempcy<br />

II


I’RINCIPIA MATHEMATxc,A.. q!<br />

ris, dccrckcc r&a WC in rationc Gcometrica ad rnodum v&xi- L2lltll<br />

tatis, Sr: parccs I&X .k?C aqualibus tcmporihs deh-ipta: decry- SL~“NDV~<br />

i?xnt in eadem ratiom


&loco quovis7) egrediatur Proj&ile<br />

fecundurn lineam quamv+<br />

re&am ZIT, & per longitudmem<br />

2) T exponatur cjufdem’<br />

velocitas fub initio tnotus. A<br />

pun&o T ad lineam Horizonta-,<br />

lem 2) C demittatur perpendiculum<br />

T C, & fecetur I) C in A<br />

UC fit Dlsl ad &‘C ue refifientia<br />

Medii, ex motu in altitudinem<br />

fub inieio orta, ad vim gravitatis;<br />

vel (quod perinde efit) ut<br />

fitre&angulumfibCDASrDT<br />

ad rehangulum fub AC & CT<br />

tit refifiencia tota fub initio mothis<br />

ad vim gravitatis. Afymptotis<br />

D C, CT, defiribatur Hyperbola<br />

quavis G TB Sfecans per enhula<br />

DG, AB in G & if j &<br />

compleatur ~a~allelogrammum<br />

D GKC, cu~us latus GK f&et<br />

AB in J& Capiatur linea N.in<br />

ratione ad &B qua I) C fit ad<br />

CT 5 & ad reti= DC pun-<br />

Bum quodvis R ere&o perpendiculo<br />

RT, quad Hyperbolz<br />

$I fT; fc re&!s EH, GK, BT


Zld FHILOSOPHI[~ NATURALIS<br />

~‘,~~~D8fi~l inde eit, cape R r xqrlalem GTIE N j & Proje&ile tempore D.Ii? TG<br />

perveniee ad punQum Y? defcribens curvam lineam I) ra F, guam<br />

punhun P kmper tangit, perveniens autem ad tiaximam ahtudinem<br />

n in perpendiculo AB, & p0ite.a f:mper approprnquans ad A-<br />

i-ymptocon T I, C. Efique velociras ejusln puntio quovis r ut Curvzx<br />

Tangens r L. .&E. 1.<br />

EfienimNad B utI)Cad CT fk~ D R ad RV,adedqueRy<br />

53<br />

9Rx B-BGT<br />

aqualis 2, I2 ” 3 & R r (id efi R Y-Yr feu ----%--I<br />

‘DR;AB-RtDGT<br />

aqualis<br />

N<br />

Expyatur jam tempus per are-<br />

•<br />

am ATIGT, & (per Legum<br />

-Coral. 2. ) difiinguatur motus<br />

corporis in duos, unum akenfus,<br />

alterum ad latus. Et cum<br />

refiitentia fit ut motus, difiinguetur<br />

etiam hzc in partes duas<br />

.partibus motus proportionales<br />

& contrarias : ideoque longitu-<br />

-do, a motu ad latus defiripta,erit<br />

(perProp. II. hujus) ut linea<br />

2, R, altitude vero (per Prop.<br />

~-XI, hujus) ut area ‘23 R x AB<br />

- R 13 G I, hoc eft, ut linea R r.<br />

Ipib autem motus initio area<br />

R B G T aqualis eit re&anguIo<br />

2) RxA ,&ideoque linea illa R t<br />

(feu BRxAB-DRxA$)<br />

N<br />

tune efi ad I> R ut AB-A$<br />

,Gu $&B ad N, id efi, ut CT<br />

ad fD C; atque adeo ut motus<br />

,in altitudinem ad motum in<br />

llongitudinem Cub initio. Cum r,<br />

iuitur R*r femper fit ut altitu-<br />

$0, ac 2) A femper ut longitudo,<br />

atque R T ad 2) R fub<br />

initio ut alcitudo ad longicudinem: neceffe et? ut R r femper fit ad<br />

!D R ut aftitudo ad lon$tudinem, k propterea ut corpus movea-<br />

Xur in linea (P r a F, quam pun&urn -r perpetuo tangit, KIT. 2).<br />

Coral.


ii producatur R T ad X ut fit RX =equaIis vR$AB, (ideit, ii<br />

corn pleatur parallelogrammum A C T r, jungatur 2) r fecans CT<br />

in 2, & producatur R T donec occurrat 2, Tin .Xj) erit Xr azqua..<br />

Iis R TIGT<br />

-- & propterea tempori proporcion~lis.<br />

N 9<br />

Coral. 2. Wnde fi capiantur innumers CR vei, quad perinde efi,<br />

innumerz 2 X9 in progrefione Geomctrica j erunt totidem Xr in<br />

progrcfione Arithmetica. Et hint Curva D rdF per tabulam Lo-<br />

$arithmorum facile delineacur.<br />

Coral. 3. Si vertice ‘D, diametro 2>E deorfum produQa, & La-<br />

.tere r&o quod fit ad 253 T ut refifientia tota, ipfo mow initio,<br />

ad vim gravitatis, ParaboIa contlruatur : velocitas quacum corpus<br />

exire debet de loco D fecundum reQam 2> T, ut in Medio uniformi<br />

refifiente defcribat Curvam D ra F9 ea ipfa erit quacum exire<br />

debet. de eodem loco 23, fecundum eandem re&am 59 • T> UC<br />

in fpatio non refiReme defcribat Parabolam. Nam Latus re-<br />

I) Y qwd. & y,<br />

&urn Parabola hujus, ipfo motus initio, efi y,<br />

-efi tGT N- feu DRxTt 2N . ReEta autem qu;E, G duceretur, Hy-<br />

perb&n GTB tangeret in G, parallela efi ipfi D K, ideoque<br />

2-c efi CKxDR & N erat gB X2)c Et propterea Yr efi<br />

‘DC<br />

-CT----*<br />

DRqxCiW CT<br />

, id et%, (ob proportionales I) A SC 2) C, 2, Y<br />

.zmcgxsp<br />

fDYqxcK x CT, &‘Larus reQum DYqztud.<br />

!&VT)<br />

- - prodit .<br />

zfDTqx@<br />

Yr<br />

2$~~$$$$,id efi (ob proportionales 2B &ClC, DA &AC)<br />

zfDA<br />

’<br />

,adeoqueadzCDT,ut21TXCDAadCTXAC;<br />

hoc<br />

- AC.%CT<br />

eft, ut refiitentia ad gravitatem.. L&E. fD.<br />

Coral. 4. Unde fi corpus de loco quovis V, data cum velocitate)<br />

ficundum retia-m quamvis pofitione datam ‘D T projiciaturj & re- :<br />

&fientia Medii ipfo moeus initio detur : inveniri potefi Curva<br />

!ZI ra,& quam cor.pus idem defcribet. Mam ex data velocitare<br />

FF<br />

datur


DE ht 0 T U datur kttus re&bm hrabok9 UC<br />

C~~~o~u~r now-n efi. Ec fhmendo 213 T<br />

ad latus illud rehm, ut efi vis<br />

gravitatis ad vim refifientiazl,<br />

datur ‘D T. Dein lecando fZI C<br />

in A, ut fit CT x AC ad<br />

I) T x CD A in eadem illa ratione<br />

gravitatis ad refiOentiam,<br />

dabitur pun&urn A. Et inde<br />

datur Curva ?> r n 14.<br />

Curd. f. Et contra, G datur<br />

Curva ‘?I r LJ F, dabitur & ver<br />

Pocitas corporis & refifientia<br />

Medii in locis iingulis r. Nam<br />

ex data ratione d’ ‘T X AC ad<br />

I) ‘T x 59 A, datur turn refifientia<br />

Medii dilb initio motus, turn<br />

latus re&um Paraboh: & inde<br />

datur etiam velocitas hub initio<br />

motus. Deinde ex longitudine _<br />

tangentis r L , datur & huic<br />

proportionalis velocitas, & ve- E<br />

locitati proportionaIis refifien-G<br />

tia in loco quovis r.<br />

Curol, 6. Cum autem longitudo<br />

zZIT fit ad latus re&um<br />

Parabolas. ut gravitas ad rehfien’tiam in 13 j St ex aufia veIocitate<br />

augeatur refifientia in eadem ratione, at latus r$kum Parabola: augeatur<br />

in ratione illa duplicata: patet longitudinem 2DT. augeri<br />

in ratione illa fimplici, adeoque +elocitati femper proportlonalem<br />

effe, neque ex angulo Cz) T mutato augeri vel minui, nifi mutetur<br />

quoque velocitas.<br />

Carol, 7, Unde liquet methodus determinandi Gurvam I>rap<br />

fzx Plwznomcnis quamproxime 3 & in& colligen$ retifiencialy ,&<br />

velokatem quacum corpus projicittir. ProJlciantur cnrpora ,duo<br />

hmilia & aqualia eadem ciam velocitate, de loco 2) 9 Cehwhn<br />

angulos diverfos C23 T, 6%)~ ( minukularum literarum locis fib..<br />

intelle&is) & cogno.f~antur loca E, f, ubi incidunt in hori,zontale<br />

planum I> C. Turn, aGmpta quacunque longicudime pro YI ‘p<br />

vel fD pr fingatur pod refifientia in ‘59 fit ad gravitatem in rzr<br />

tione


PRINerPIA MATHEB/liATfCA.<br />

219<br />

tione qua&et, & exponatur rario illa per Jongitudinem quamvis<br />

LIBER<br />

S&X Deinde per computationem 9 ex ~ongitudinc illa affumpta sEcusoUj<br />

2I 37, inveniantur fongitudines fD F2 'B;f ac de ratione r;f kB &, per<br />

ncalculum inventa, auferatur ratio eadem<br />

per experimentum inventa, & exponatur<br />

differentia per perpendicuhm nilAL Idem<br />

fat iterum ac tertio, affumendo femper<br />

novam refifientia ad gravitatem rationem<br />

8 M, & colligendo novam dift’erentiam<br />

MN Ducanhr autem differenti,?: affirmativa ad unam partem<br />

reQx Sill, & negative ad alteram ; or per pun&~ AT, N, 1~ agatur<br />

cwrva regularis NNN i‘ecans re&am SikZhIM in X, & erit SX<br />

atera ratio refifientia ad gravitatem, quam invenire oportuit. Ex<br />

hat ratione colligenda eit: longitude ‘I> F per calculum; & longicudo<br />

qua: fit ad affumpram’longitudinem m fpj ut longitude TI F<br />

per experimenturn cognita ad longitudinem 21 F modo inventam,<br />

erit Vera longitudo 9 T. C&a inventa, habetur turn Curva linea<br />

2) r d F quam corpus defcribit f turn corporis velocitas & refifientia<br />

in locis hngulis.<br />

Cdterum, refifientiam corporum effe ii1 ratione veI+tatis, Hy..<br />

pothefis efi magis Mathematics quam .Naturalis, Obtmet bat ratie<br />

quamproxime ubi corpora~in Medlrs rigore aliquo przdltls tardifflme<br />

moventur. In Mediis autem qu;p. rigore omni vacant refifientia<br />

corporum lunt in duplicata rati~one velocitatum. Etenim<br />

aQione corporis vclocioris communicatur eidem Medii quantitati,<br />

tempore minore, motus major in ratione majoris velocitatis; adeoque<br />

tempore .zquali (ob majorem Medii quantitatem perturba-<br />

Earn) communicatur aotus in duplicata ratione major; efiqve red<br />

Gfientia (per motus Legem II& 1x1) ut motus communlcatus.<br />

ideamus igitur quales oriantur motus ex hat lege ReGfientls,<br />

FE.2<br />

SECTIO


Ee Mar u<br />

EoRronuar<br />

PROPOSIT V. T’HEQREMA III.<br />

Si t&pri reJj!ihw in ~elocitiltis ratione dhplicdta, & idem Ji$g<br />

vi &$a per Medi~mJirMihe mocuetur; tempara vero JumaBl<br />

tar in progrejhe Geometrica d minara’bzu terminis ad rnaj,res<br />

pergente : dice quad gelocitates initio ~ngulo~um zemporum<br />

f&zt in eadem progrefiane Geometrica ‘inT)er[e, &, pod. fia&<br />

fint cequaliu qw Jngulir temporibus deJ&btlnttir.<br />

I%m quoniam quadrato velocitaais<br />

proportionalis efi refa.Ctentia Medii,<br />

& refiitentk proportionale efi<br />

decrementum yelocitatis; fi tempus 34<br />

in particulas innumeras zquales divi-<br />

: c’<br />

datur, quadrata velocitatum hgulis i<br />

‘.<br />

temporum initiis erunt velocitatum \<br />

earundem,differentiis proportionalia.<br />

I,<br />

Sunto temporis particalze illaz AK,<br />

:In<br />

“-----<br />

KL, LM, &e: in re&a CD fumptz,<br />

;<br />

& erigantur perpendicula AB, Kk, !<br />

: i . G”<br />

: j .<br />

G ,- D<br />

L I, Mmr &c, Jkhwerboh B k Gff8 G.<br />

ce&o~C~AfymptdtTis reQanguIis’ C$, CN dekriptze, occurrentia<br />

in B, k, Z, ‘m,&c, & erip A B ad K k ut C K ad GA, & divifim<br />

AB--Kk ad Kk ut AK ad CA, Sr viciffim AB-Kk ad.AK<br />

ut Kk ad CA, adeoque ut AB xXk ad AB xCA. Unde, cum<br />

,4K & AB xCA dentur, erit A$3 r,Kk ut AB x Kk’j & ultimo,<br />

ubi coeunt A B & K kj ut A B 4. Et Chili argument0 erunc K k-L t,<br />

&k-Mm, &c,ut,Kk~,L Zg,&c. Linearumigitur AB, Kk, .iX Mm<br />

I


PRIP+J~H’~A MATHEMATIcA. 5.211<br />

quadrata funt ut earundemdifferentkj & idcirco cum quadrata ve- LIIIER<br />

locitatum fuerint eciam ut ipfarum different&, fimilis wit amba- sECUNDUS<br />

rum progrefio. Qo demonitrato, conkqwens efi etiam ut area:<br />

his lineis defcripte fint in progreffiane conGmiii cum fpatiis quzveloci<br />

tat&us defcri buntur. Ergo ii velocitas initio primi temporis<br />

AK exponatur per lineam AB, 8~ velocitas initio kcundi K&<br />

per lineam I &c. zq~alias-<br />

$&E. f;r),<br />

Carol. I. Patec ergo quod, fi tempus exponatur per Afymptori<br />

partem quamvis AZ), & velocitas in princlpio tcmporis per ordinatim<br />

applicatam AB j velocitas in fine remporis exponetur per<br />

ordinatam 2, G, St fpatium totum defkiptum, per aream Hyperbolicam<br />

adjacentem AB Gr); necnon fpatium quod corpus aliquad<br />

eodem tempore A I), velocitate prima- AB, in.; Medio .non::<br />

refifiente defcribere poffet, per re&angulum A B x AD. .<br />

Coral. z; Unde datur fpatium in Medib refifiente defcriptum, ~2..<br />

piendo illud adbfpatiuti quad velocitate uniformi AB in medio non<br />

refifience fimul. d‘efcribi p&et, ut efi area Hyperbolica LIB G.Zd<br />

ad re&angulum AB x AD.,<br />

C&l, 3. Datur etiam refifientia Medii, fiarueado earn ipfo motus<br />

initio zqualem effe vi uniformi cencripetce, qu;e in cadentecorpore;<br />

ternpore. AC, in ;Medio non refifienre, generare poflkt velocitatem<br />

A B, Nam G ducatur B 2” qwz tangat Hyperbolam in B,<br />

8c. occurrat.Afymptoto in Fj reQa AT aqudis erit ipfi AC, &<br />

ternpus exponet quo refifientia prima uniforniiter continuata tolle-<br />

J!e poiree *elocitatem totam AB;<br />

Cowl ‘4. Eo ,inde ‘dakur eciam,proportib hujw refifientia: ad vim,<br />

gavitatis;,, gliamve quamvis datani vim ten tripe tam. I<br />

Carol. 5. Et viceverfa, ii datur proppkio refi$entik ad datam<br />

quamvis vim centripecam j datur tempus AC, quo vis centripeta<br />

I;efifientiz ;lequalis generare poffk velocitatern quamvis AB : &‘inde


% 2’2 ‘P’WItOSQPH’IA NATURALHS<br />

de datur pun&urn B per quod Hyperbola, AfymptotisC<br />

tb”,~~~~~~r’~~ defc&i d&et; ut & fpatium Afi 62), qllod corpus ilxipiendo<br />

mocum fiium cum velocicate illa AB, tempore quovis AD, in Mew<br />

die fimilari refiitente defiribere potefi.<br />

Afymptotis re&angulis C’JD,<br />

CH defkripta Hyperbola quavis.BbEekcanteperpendicula<br />

AB,ab,D E,de, in B,6,E+,<br />

I exponantur velocitates initi-<br />

X-3<br />

ales per perpendicula A B,<br />

DE, Sr tempora per lineas<br />

Aa, D d, Efi ergo ut Aa ad<br />

2, dita (per Wypotbefin) ‘D B<br />

ad AB, & ita (ex natura Myperbolaz)<br />

CA ad CD j 8~ COIIIponendo,<br />

ita Ca ad Cd. Ergo C<br />

.area AB&a, I> E ed hoc efi, fpatia defcripta aquantur inter fe,<br />

& velocitates prim% AB, 2, E funt ultimis a li, de, & p’ropterea<br />

(dividenda) partibus etiam fuis amifis A B -ah 59 E - de pro-<br />

.portionales. g E. 9.<br />

PRQPOSI I[. TMEOREMA V.<br />

$orpord Sphmicca guihs re&‘itur in dtiplicata wtione vehitatzm,<br />

temporibus quce rant ut motto primi direffe & rej$enti~ pri-<br />

.wrtl invevfe, dmittent .ptwtes mottim proportionaZes hh4-, &<br />

@atid de[cribent tempo&w a$% hz velocitutes prhrm A&k<br />

+proportionulid.


RINCIPIA MATHEMATIC’& eq-<br />

conjuntiim. Igicur ut partes ilk fint totis proportionales, debe- LIBEII<br />

bit refifientia & tempus conjun&im efk UC motus. Proinde tern- SECIJND~~:<br />

pus eric ut: motus dire&e & refifientia inverfk. Qare temporum<br />

particu!is in ea racione fimpris , corpora amittenr femper parciculas<br />

motuum proportionales totis, adeoque retinebunt velocitates<br />

in ratione prima. Et ob datam velocitatum rationem, defcribent<br />

~Gxiper fpatia qua2 tint ut velocitates prim= & tempora conjuntii~~.<br />

,$I?& E. D.<br />

Carol, 1. Igitur fi atquivelocibus corporibus refifiitur in duplicata<br />

rat&e diametrorum : Globi homogenei quibufcunque cum velocitytibus<br />

moti, defcribendo fpatia diamctris Louis proportionalla, amitcent<br />

partes motuum proportionales totis. Motus enim Globi CUjufque<br />

erit ut ejus velocitas & Maffa conjuntiim, id efi, ut velocitas<br />

& cubus diametri; refifientia (per HypotheGn) erit ut quadrarum<br />

diametri & quadratum velocitatis conjuntiim; & tempus (per<br />

hanc Propofitionem) efi in ratione priore dire&e & ratione poiteriore<br />

inverfe, id efi, ut diameter dire&e & velocitas inverfiee; adeoque<br />

rpatium (tempori & velocitati proportionale) et% ut diameter.<br />

CoroL 2. ,Si xquivelocibus corporibus refifiitur in rarione Mquialtera<br />

diame,trorum : Globi homogenei quibufcunque cum velocitatibus<br />

mot& dekribendo fparia in fefquialtera racione diametroruma<br />

amittent partes motuum proportionales totis.<br />

,;CoroG, 3, EC, univertiliter, fi azquivelocibus corporibus refifiitur in<br />

ratio& dignitatis cujukunque diametrorum : cpa.tia quibus Globi<br />

homogenei, quibufcunque cum velocitatibus mote, amitcent partes<br />

motuum proporcionales totis, erunt u~cubi diametrorum ad dignitatem<br />

illam‘ applicati. Sunto diametri D 8E E; & ii refiitentiaz2 .<br />

ubi velocirates xquaies ponuntur, fint ut D” & E”: ipatia quibus<br />

Globi., ~uibwkcunque cum velocitatibus moti, amittent partes rn?-<br />

fuum proportionales totlsj erunt ur D3-n & ES-~. Igrtur defcrlbendo<br />

fpatia ipfi~ D3 -+ & E3-+ proportionaiia, retinebunt veloci-<br />

,<br />

tares in eadem ratione ad invicem ac fub initio.<br />

Coral; 4, Qlod fi Globi non fmt homogenei, fpatiu.m a Clobo<br />

&&ore defcriptum augeri debet in ratione denfitatls. Lotus<br />

enim, G3b pari velocitate, major efi in ratione denfitatrs, & tempus<br />

(per. hanc Propofitionem) augetur in ratione rnotus dire&e, ac<br />

fpatium dekrip turn in ratione remporis.


F) E RI Cl 'T u &ral, r, it fi Globi moveantur in Mediis dive&; ,fpatium in<br />

CoRrOftU>l h/ledio, quad csteris paribus magis refifiit, dimifiuendum erit ia<br />

ratione majoris refiOentia. Tempus enim ( per hanc .Propofitiol<br />

nem) diminuctur in done refifienciaz au&z, & $atiuin in r+<br />

tione temporis.<br />

Genitafil voco quantitatem omnem qua2 ex lateribus vel terminis<br />

quibufcunque, in Arithmetica per multiplicationem, divifionem,<br />

& extra&ionem radicum ; in Geomecria per inventionem vel contcntorum<br />

& lacerum, vel extremarum & mediarum proportionalium,<br />

abijue additione & ~ubdu&ione geheratur. Ejufinodi quantitates<br />

filnt FaQi, Quoti, Radices, Reaangula, Qyadrata, Cubi, Latera<br />

quadrata, Lacera cubica,& fimiles. Has quantitates ut indeterminatas<br />

& infiabiles, & quafi mocu fluxuve ,perpetuo crekentes vel decreficnres,<br />

hit confider0 j & earum incremen ta vel decremen ta momentanea<br />

fiub nomine Momentorum incelligo: ita ut incrementa pro<br />

momentis addititiis feu afl?rmativis, ac decrementti pro filbdufiitiis<br />

ku negativis habeantur. Cave tamen intellexeris particulas finitas,<br />

Particulz finita non fkt momenta, kd quantitates ip& ex<br />

momentis genita. Int,elligenda’fint principia jamjam nafientia finitarum<br />

,magnitudinum. Neque enim fpe&wr in hoc Lemmate<br />

magnicudo momentorum, kd prima nafientium propkwtio, Eel<br />

dem recidit fa loco momentorum ufurpentur vel velocitates incre.<br />

mencorum ac decrementorum ) (quas etiam motus , mucationes<br />

& fluxiones quanticatum nominare Jicet) vel finitaz qua2vis quantirates<br />

velocitatibus hike proportionales. Eateris autem cujufque<br />

generancis Coefficiens efk quantitas, quz oricur applicando Geni-<br />

tam ad hoc latus,<br />

lgitur fenCus Lektmatis efi, W ii quantitatam<br />

perpetuo motu crefcentium vel decrefcentium A3<br />

arumcunque<br />

C, &c. mom<br />

menta, vel mutationum velocitates dicancur a3 6, c, kc, momentum<br />

vel mutatio geniti re&anguli A B fuerit a B +b A, & geniti con-<br />

..sengi A B C .momen.tum- fuerit a B C -+- Ei A. C + c A B : & genitarum<br />

,digni-


A -1 -2212 32 & - gad-* refpe&ive. EC generaliter, uc dignitatis<br />

N--nr<br />

cujufcunque AS momentum fuerit ~LZ AT. Item ut Gcnicaz<br />

A’B mamentum fuerit ZUA B + b A” 5 & Genitz 43 I3 CL momen-<br />

A3<br />

turn 3aAzB4Cx+.+bA3 B3 C++ zcA3 B+ C; & Genitz y Bfi<br />

-<br />

;e A?B-” momentum 3dAIB-” - 2 bA3 BL3: & fit in cxreris. ’<br />

&kmonfiratur v&o Lemma in hunt modwm.<br />

C~s. I. Reeangulum quodvis motu perpetuo au&urn A B,<br />

ubi de lateribus A, & B deerant momentorum dimidia i a & : 6,<br />

fuit A-$a in B-fb, ku AB-$dB-tbA+tdbj & quam primum<br />

latera A & B alteris momentorum dimidiis au&a funt, evadie,<br />

A-t-$a inB+$b Ceu AB4-faB-kbA+iab. Dehoc reQan-<br />

&lo fubducatur. re+ngulum prius, & manebic exceffus a B + b A.<br />

Igitur laterum incrementis totis a & b generatur refkanguli incrementumaB+bA.<br />

.&,!Z.D.<br />

Gas. 2. Ponatur AB kmper zquale C, & contenti ABC feu<br />

G C momenttim (per Gas. I.) erit g C 3-c G, id cR (h pro G & g<br />

fcribantur AB &;zB+bA) aBC+bAC+cAB. Etpar efi ratio<br />

conrenti fub lateribus quotcunque. .L& E. I>.<br />

CM. 3. Ponantur latera A, B, C fibi mutuo limper aqualia j &<br />

ipfius A”, id efi re&anguli A B, momentum d B + b A erit z&A, ipfms<br />

autem A3, id elt contenti A B C , momentum a B C +b A C<br />

+EA.B erit 3aA’. Et eodem argument0 momentum dignitatis<br />

cujufcunque A” efi n a An+‘* &E. D.<br />

Cm. 4. Unde cum 2 in A fit 1, momentum ipfius f A d&&n<br />

in A, una cum$ du&o in ct erit momentum ipfius I, id e$ ni-<br />

hil. Proinde momentum ipfius i feu ipfius A-’ eR 5. Et ge-<br />

neraliter cum & in An fit x2 momentum ipfius A$ d&urn in‘ A!<br />

$.<br />

Gg<br />

una


I<br />

i.,~~P~f~~ una cllm -LV in 71 a Au-x erit nihil. Et proprerea mornenyym +,<br />

fius gn feu A-” eric - sIa L& E 53.<br />

C~S. 5, Et cum A: in A’; fit A, momentum<br />

ipfius A$ du&um in<br />

2 At erit a, per Gas, 3 : ideoque momentum ipfius A$ erit -&<br />

2A5'<br />

five f&A-+. Et generaliter ii ponatur A ?rrquak B, erit Am z:-<br />

quale B’J, ideoque ma Amy-r zqude tib B”-‘j & md A-’ aqua-<br />

le n b 8-I fiu nbA -f, adeoque Tu A? aquale b; id CR,. &quale,<br />

moment0 ipfius A 5, &E. ED.<br />

&s. 6. Igitur Genita cujukufique Am B” momentum efi homentunl<br />

ipfius Am du&.um in B”; nna, culin fnom.ento ipfius B” du.-.,.<br />

&to in Am, id efi r)z d A”-’ @’ + B b B”-’ A” j idclue five digtiiratum<br />

indices l?a & 1~ fint integri numeri vel fratii, five afifmativi<br />

vel negativi. Et par efi ratio, contetiti fub pluribus dignitati-.<br />

- .<br />

bus. &E. D.<br />

~oroZ, I. Hint in continue proportionalibus, fi rePminus UIW,.<br />

datur, momenta terminofum reliquornm erunc hit i.ickm terqhi<br />

mui tiplicati per, nw-neftim ir?terval~lozu’III inker ‘I@%- & t&illiUfi<br />

datum. jtunto A, B’, .C,. D,- E?, I? c~o~tkt~e:‘prapor~~o~aifes j & fi<br />

detur terminus” (Z, momenta r&quorum terminorum erunt inter.<br />

i’e ut- zA, --a Ii); zE; 3,F.<br />

:;@-rfiJ, ..j, Ec’.:;“. I i n ,,quatuor propartionafibw dtiz medk. dentur,.<br />

tiknerlta egtremarum erunt ut eadem extren-w. Idem titellig~n-<br />

&III eR dd lriferibus retianguli cujufcunque dati.<br />

Coral. 3, Et ii fitmma vel diferentia duorum qtiadratorum detur,,<br />

momenta laterwm erunt reciproce ut latera:.<br />

Eri literis qug &hi cum Geomctra peritiffi-&no 6. G; L&MtzSaa+<br />

nis abhinc &ccey~ intcr@ebwt, : cuffs fig$ficsarem me cornpot&<br />

efk methtidi determinandi Maximas & Minimas, ducendi Tangente.s,,<br />

& fimilia +agendi,- qua in terpinis fwdis azqu8e a,c in rati,or<br />

sialibus ptoce B e:ret:, & lit.eris tran@ofitis hanc fentW$iam involven-<br />

1 . , tibus;


PROPOSITIO VIII. Y~WKIREMA VI.<br />

$; corpus in Me&o uniformi, Gmitate ’ uniformiter ugente, ye &!a<br />

ascend&t vel defcendat, & jahm toturn de[criptum dzJ&.zgtiatar<br />

in partes cyuales, inque principik Jingu/arum parthn2<br />

(addend0 refiientiam Medii ad vim gravitatis, quando COY-<br />

_ pus arcendit, vel Jubducendo $farn quando corpus def&nditJ<br />

co.l@ntadr Tires abfoht& j dice quod Tires i/b ahJob jiint<br />

in progreflone Geotietrica.<br />

Exponatur enim vis gra+ttis per datam lineam AC; refiflen.<br />

ria per lineam indefkicam AK; vis abfzhta in defcenfu corporis<br />

per differentiam K’i velocitas corporis .per lineam AT (qw fir<br />

media proportionah .inter AK & AC, ideoque in fubduplicata<br />

ratione refifientia j> incrementurn refifiqntia data temporis particu-<br />

Ia faGurn per lineolam JKL, &‘contemporwieum velocitatls incrementum<br />

er lineolam “P.$$ 82 centro C Afymptocis rekwgulis<br />

CA, C d . defcribatur Hyperbola quzvis BATS, eretiis perpendir;ulis~B,<br />

KN, LO> TRR, L@’ occurrens in,B, N, 0, R, 5’. QOnidm<br />

AK efk ut AT q 9 erit”l$jus momentum .K L ut illius mome&urn<br />

zAy ,$& id & ut AtY in KC. Nam velocitatis increm&iurn<br />

T,& (per mow Leg. II.> proportionale eit vi generanti KC.<br />

Componatur ratio ipfius KL cum ration,~ ipfius IiT.&?, SE 6et r&tangulumKLxKNutA"iPxKi~xIC~;<br />

hocefiP, obdatumreeangulum<br />

KCXKN, UtA*F. Atqut are32 Hyperbolic32 KNOL<br />

ad reQangulum ML;-~Kti~atio ultiina, ubi coeunt pun&a K&L,<br />

+k aeyualitatis. Ergo area il!a Hyperbolica evanekcns 4% ut AT’.<br />

Compofiitur igitur area rota Hyperbolica. A B 0 E ex particuljs<br />

KNO .,?I, velocieati’ A5? fernper proportlonalibusJ &~,piopt~rea<br />

fpatio velocitate ifia defcripto, proporrlonalls ek Divrdatur’ jam<br />

area illa in pastes aquales k? B MI3 i MATIC, IL NO L&c. 82 vi-<br />

G.8 2 res


azs pHIKWX’HI& hh=$PWkEIS<br />

1) ,>, h?OT u res abroluw AC, IC, KC, L C, kc. erunt in progrefikone Gee-<br />

Conl’onu~l metrjca, $ B. 59. Et Gmili argumento, in afcenfu corporis, funlendo,<br />

ad contrariam partem pun&i A, zquales areas. AB mi,<br />

i ye gkk, b B o I, kc. confkabit quad vires abfolutz AC, iC, k C, ZC, &c.<br />

-&nc cofltinue proportionales. ldeoque Ii fpatia omnia in aibenfii &<br />

dei’cenh capiancur azqualia ; omnes vires abfolutz IG, kc, iC, AC>,<br />

.IC, KC, &IC> k-42, crunt continue prQpo.rtionales, $$kLCDr<br />

&~roZ; 1,. Rinc ii fpatium defcriptum exbonatur per aream l3y-<br />

~erbolichn AB2\T.f


PRINCIPIA MATHEMATICX 223<br />

tatem illam datam in fi~bduplicata ratione, quam habet vis Gravi- LIBER<br />

SECUNDUStaris<br />

ad ,Uedii. refiitentiam illam cognitam.<br />

PROPOSHTIO, IX. THEOREMA VII.<br />

.<br />

Re&a AC, qua vis gravitatis exponitur, perpendicularis & LEA<br />

qualis ducatur AD. Centro ‘D kmidiametro A’D dehibatur turn<br />

Circuli quadrans A,? E, cum Hyperbola re&angula A YZ axenx<br />

habens AX, verticem prJncipalem A & Afymptoton fz) C. Juhgantur<br />

Cog, D Ip, 8r: erit fe&or Circularis At ‘53 ut tempus afcenfus<br />

omnis futuri j & kCtor Hyperbolicus AT23 ut temyus defcenfus<br />

. omnis pr33eriti. Si modo feQorum Tangentes Ap, AbP ht ut<br />

velocitates.<br />

Gas. I. Agatur eni+ I) vq abhindens k&to& k”Dt 8i: trianguli<br />

k$Ezap momenta,. feu. particulas quam minimas fimul defcriptas<br />

tDv & $fDq. CQm particulz ilk, ob angulum communem<br />

9, fiunc in dup1icat.a ratione laterum, erit particuia t23 v<br />

Ergo fe&oris particula ,tFa weit Qt $f,<br />

id efi-, ut velocitatis, de-<br />

&mcntum quam minimum ps diretie et ‘vis illa Ck quz velocitatem<br />

dimig.uit inverfet, atque adeo ut: particula temporis ,decremento<br />

rei’pondens.. Et cpmponendo fit i’umma particulasum omnium,<br />

t 13 +?i’fl k&ore AD t , ut lirkma- particularurn temporis<br />

fingulis velocitatis decrefcentis A,P particulis amifis p 4 refpondentium,,:<br />

ufq\le. ‘dum velocitas ‘Zlla- if1 nihilum diminuta eva4<br />

nuerit j hoc eti, fid-or ptbx+A~t efi ut afienhs tot+ futuri.<br />

Eempus, $ig$u!2n<br />

, .<br />

., .’ .,*..A,a’ i.8.


~["~mcxI)rA MATHEMAT’I’CA... @ 5<br />

fs R generanturj ut iilmma particularum .fi&oris AT-Dj ‘id. elf, LlDEIt<br />

ternpus torum ut feQor POtUS. L&E. 53,<br />

SECUNDUS;-<br />

C&, 1. Hint ii A3 azquetw quart32 parri ipiius AC, fpat& 1<br />

quad corpus cemppre quovis cadendo defcribic, erit ad fpatium<br />

quad- corpus velocltate maxm~a AC, eodem cempore uniformiter<br />

progrediendo defcribere poteft, ut area AB iVK+, qun fparium<br />

cadendo defcrip tum exponitur, ad aream A?+D qua tempus ex-,<br />

ponicur. Nam cum fit AC ad AT UC A’T ad AK, erit (per<br />

CoroJ. I, Lem. II hujus) LK ad P&‘.LIc 2AK ad A-P, hoc eft,<br />

UC 2 A ‘p ad AC, 8~ inde /, K ad t ‘T &j, ut AT ad ($ A;C vel)<br />

AB; elt & KN’ad (AC vel) AD UC AB ad CK; itaque ex<br />

quo I, KN ad cD,Tg ut A*P ad CK. Sed erac D 6P$ad<br />

D TV ut CK ad AC. Ergo rurfus ex. xquo L ICN efi ad -23‘rPV<br />

ut AT ad AC; 110~ efi, UC veiocitas corporis cadentis ad velo&<br />

tatem maximam quam corpus cadendo pocefi acquirere. Cum<br />

igitur arearum AB NK Sr A TZ) momenta L ICiV & I) TF<br />

funt ut vclociaaces, erunt arearum illarum partes omnes fimul<br />

&enit;E: ut 6patia fimul dekripra 3 ideoque arez cotir: ab initio<br />

genitz ABiVK.Sr ArD UC fpatia tota ab initio dekenfus dekripta.<br />

& E# 2).<br />

CLVV,!; 2. ldem conkquitur etiam de fpatio quad in af&nru &<br />

kribitur. Nimirum quad fpatium illud omne iit ad fiatium, unifo,rmi<br />

cum velacitate AC eodem tempsre defcriptum, ut efi arca<br />

ABnk adk&orem AI>t.<br />

CwoZ. 3!,. Velocitas corporis tempore ATTI cadentis efi ad velocitatem,<br />

quam eodem tempore in fpacio non refiItente acquireret,<br />

ut triangulum AT’D ad k&orem Hyperbolicum A’FD~<br />

Nam velocitas in Medio non refiftente forec UC rempus ATD, &<br />

in Medio refifiente efi ut AT, id eft, ut triangulum AT D. Ec<br />

velocirates ilk initio, dekenfus rrquantur inter k, perinde ut arez<br />

illa: SZZI,. AT.CD.<br />

; I.<br />

Co&. 4. Eodem argumento velocitas in afienfn. ifi ad velocim;<br />

tern; qua corpus eodem tempore in. fpatio non refifiente omnem<br />

fuum afcendendi motum amittere poffet, ut triangulum Ap 92 ad<br />

k&orem Circularem At 59 j five ut re&a Ap ad arcum At.<br />

CuroZ..$. Efi igitur tempus quo. corpus in Medio. refiftente cadendo.<br />

velocitatem .AF acquirit, ad tempus quo velocitatem manimam<br />

AC in fpatio,non refifiente cadendo acquirere poffet, ut [e&ok<br />

&‘D 27’ ad triqngulum AD Cl 6-z teqxas~ quo velocitatem A&&


loca quarum corporis in hat<br />

curve ah Fad gpergenris;<br />

wG;I;‘,. HC, IT?, K E or- /<br />

dinata quatuor parallela: ab’<br />

h.is pun&is ad. horizontem I3


R cm<br />

%&:A. zjg<br />

t tempera quibus corpus defcribit arcus GE& .H.& ermt in I,TI!P,r<br />

fubduplicata ratione altitudinum LI-6, Al% q~as corpus tempo- SE!::J:~.~,~~~<br />

ribus illis defiribere poflk, a tangentibus cadenda : & velocitases<br />

eruflt ut longitudines defixiptz GH, HI dire& & tempera inverfk,<br />

EXponantur tempera per T & 8, k velocitaces per<br />

GA? & AYI#<br />

*- . & decremel3tum velocitatis rempore t fa&um ex-<br />

=T- $<br />

GH HI<br />

ponetur per -T- - l.. Hoc decrementurn oritur a refiltenria<br />

corpus retardan te & gravitate corpus acceleran te. Gravitas in<br />

csrpore cadente & fjpatium NI cadendo def‘cribente, generac ve-<br />

Bociratem qua duplum illud fpatium eodem tempore de~ri& po3-<br />

/<br />

tuiffet (ut GaZX&s demonfiravit) id efi, velocitatem - : at<br />

t<br />

in corpore arcum WI defcribente, au&et arcum ihm fola longi-<br />

MIX A7x<br />

tudine HI-HA? I&I NI y ideoque generat tantum vclo-<br />

2MlxNI<br />

citatem fl txWI *<br />

Addatur hax velocitas ad decrementum<br />

przedi&hn, & habebitw decrementum velocitatis ex refiftentia<br />

GH HI 2i%!~xNI<br />

fola oriundum) nempe T<br />

Proindeque<br />

-7+---* tx23.r<br />

cum gravitas eodem tempore in corpore cadente generet velocitatem<br />

ZNI GET HI<br />

- j Refifientia erit ad Cravitatem ut T -T + 2MlxN.Z<br />

if<br />

ad<br />

2x1<br />

----Y<br />

z<br />

five ut txGH<br />

T<br />

-HI+ ’ M’xN1<br />

HI<br />

ad 2 PJP 0<br />

ro abfkiflis CB, CDs CE tiribantur -03 Q, z o, Pro<br />

O$EZaZ CN fixib?tur & pro MI fcribatur feries qux:libet<br />

QofRoo+sQ3+ikC.<br />

I& fk-iei termini omnes pofi primum<br />

nempe R D o + S o3 $8~. erun t NI, 6r Qrdinata ‘DJ, EK, & h’d<br />

erunt P-Q-ROD--So3 --&z&c, I?--2@--4R00°- XSo3--&c,<br />

& P+C&-R00+S03-&c~ refpe&ive. Et quadrando difrerentias<br />

Ordinararum B G - CH & CH- 531, & ad quadrata pro-.<br />

deuntia addend0 quadrata ipfarum B C,. CD, Iaabebuneur arcuum<br />

Gf& Nil quadrata m.+-QQo--2Q~b~-+~tc,, SC<br />

,-.n<br />

OO+CJ$&<br />

tx.EiI


ventos endit !!C%!! d H -j-<br />

3 5<br />

zR<br />

Et cum 2 NI fit 2 R 00,<br />

f$SOO<br />

Wentia jam erit ad Cravitatem ut -_- 1/ I +- QQ -1 , ad 2 Ro o 41 .<br />

2K<br />

id cfi, ut @dx++Qad @XR.<br />

Velocitas autem ea efk quacum corpus de loco quovis H, fetecundum<br />

tangentem H.iV’ egrediens, in Parabola diametrum HC<br />

& latus re&tum TI.a HNq feu ‘+ R ,_ habente, deinceps in vacua<br />

moveri pot&.<br />

Et refifientia ef% ut Medii denfitas & quadratum velocitatis<br />

conjun&im, 82 propterea edii denfitas eft ut refifientia dir&e<br />

& quadratum velocitatis inverfe, id eA, ut dire&<br />

& 1-kQQ-<br />

K.<br />

mvede,<br />

hoc efi, ut<br />

JW/+<br />

CoroL E. Si tangens HN producatur utrinque donec occurrae<br />

HT<br />

Ord’inatx cuilibet A’F in T: wit xc azqualis d I+ , adeo*<br />

que in filperioribus pro 4 I +QQkribi pot&<br />

Refifientia erit aidravltateni uc 3 S X.HT ad 4R<br />

S%AC<br />

citas crit ut + -) & Medii denfitas erit ut Rx p-4r<br />

AC&<br />

Cor51. 2. Et hint, fi Curva linea 5? FHRdefiniatur per relarrionem<br />

inter bakm k‘eu abkiffam AC 8a ordiwim apphcatani<br />

CH,<br />

S


CH, (ut moris efi) Sr valor ordinatim applicatz refolvatur io k- L ! I! rlf<br />

rriem convergen tern : Problema per primos kriei tcrminos expc- s Lcz ti >: ls ” i.<br />

dice folvetur, ut in exemplis fequentibus.<br />

ExempZ. I, Sit Linea cp” E’Ng Semicirculus fuper diamecro P-q<br />

defcriptus, & requiratur Medii denfitas quz faciat LX ProjeMu<br />

in hat linea moveatur.<br />

Brfecerur diameter T’ g in A, die A 2 U> AC u, CH e, &I<br />

CD 0: 82 erit Dlq ku ~~2--n~g=nn-au-220-00, feu<br />

ee--zao-oo3 & radice per mechodum nodtram extra&a, fret<br />

a303<br />

~I,e-a_D-~e-~~o~-~-03--- -&c. p-lit fcribatur no<br />

e 3e3 2e5<br />

pro ee+ua, & evadet<br />

!DI==e--~-~~-!-.‘!-~c~<br />

J-Jujufinodi feries difiinguo in terminos f’uccefivos in hunt madum,<br />

Terminum primum appello in quo quantitas infinite parva<br />

0 non extat; fecundurn in quo quantitas illa efi unius dimenfionis,<br />

tertium in quo extat<br />

duarum) quartum in quo<br />

trium efi, & fit in infinitum.<br />

Et primus terminus<br />

qui hit efi e, denotabit femper<br />

longitudinem Qrdinata:<br />

CH infifientis ad initium<br />

indefinitz quantitatis 05 6%<br />

cundus terminus qui hit eft<br />

y3 denotabit differentiam<br />

inter CH 8~ 9 N, id eft-, hneolam MN quz abfcinditur corn--<br />

plendo para~~~~qgmnm-n HC I) A?, atque adeo pofitionem rangentis<br />

HA! fernper determinat : ut in hoc cafu capiendo MN ad<br />

H.ikf ut efi f.f ad 0, ku a ad e.<br />

e<br />

Terminus tertius qui hit efi<br />

‘K!-‘o defignabit<br />

2e3<br />

lineolam IN qua jacet inter tangentem G= curvam,<br />

adeoque determinat anguium contatius PUN feu curvaturam<br />

quam curve ‘linea habct 1n A? Si lineala illa IN finicx efi<br />

magnitudinis 9 defignabitur per cerminum terrium ma CUQI ieN<br />

quentibus in in6nitum. At fi lineola illa minuatur in infinitum,<br />

,I411 2 termi-


ao DLnOO annui<br />

CoIlfcratur ,jam iirieS 6 - e - .re3 - - - - &C, CUm Ierie<br />

2e5<br />

prodibit Me&i dcnfitas UC -f, hoc efil (ob datam a,) ut %, f&l<br />

llre<br />

AC<br />

.-- id ef& ut tangentis Iongitudo iIIa HT qw ad knzidime-<br />

GN’<br />

trum AF ipfi T & normaliter infifientem terminatur: & refifientia<br />

erit ad gravitatem UC 3 LZ ad 212, id efi, ut 3 AC ad CircuE<br />

diameerum ‘T ..$$ veloci tas autem erit ut 4 &‘H, @yare fi carp<br />

jufia cum velocltate fkcundum lineam ipfi I”& parallelam exeat<br />

de Ioco F, & Medii denfitas in fingulis locis N fit ut longitudo<br />

tangentis HT, & refikntia etiam in loco aliquo N fit ad<br />

vim gravitatis ut 3 AC ad T R, corpus illud dekribet Circuli<br />

quadran tern F Ha J&E. P.<br />

At G corpus idem de loco T, kcundum lineam ipfi T 2 perpendicularem<br />

egrederetur, 82 in arcu femicirculi T Fg moveri<br />

inciperet, fumenda effet AC fku a ad contrarias partes centri A,<br />

& proptcrea Signum ejus mutandum e&t & fcribendum -lz pro<br />

+ LA Quo pa&o prodiret Medii de&as ut -t. Negativam<br />

autem denfitatem, hoc efi, qw motus corporum accelerat> Na,<br />

tura non admittit: & propterea naturaliter fieri non pot&:, 11,<br />

corpus afiendendo a T defcribat Circuli quadrantem TE Ad<br />

hunt eEe&m deberet corpus a Medio impellente accelerari, non<br />

a refiitente impediri*<br />

’ Exe~$. 2. Sit linea T Y;H@ Parabola, axem habens AX; horkzonti<br />

‘P R perpendicularem, & requiratur Medii de&as qw<br />

faciat ut ProjieLZile in ipfa moveatur.<br />

Ex natm Parabola , re&anguIum T 23 2 zquafe eR re&ngulo,<br />

iiab ordinac;t 52 I.. (5s re@a aligua data: hoc eRs .fi dicantur<br />

se&a.


endus cffet hujus feriei kcundus terminus ‘9 o pro Q, ter-<br />

- ~.___<br />

tius item terminus O; pro ROQ. CLm vero pIUres non fint ter-<br />

mini, debebit quarti coefficiens § evanekere, 8r propterea quan-<br />

S<br />

titas<br />

cui Medii denfitas pro,portionaIis e[t, nihil<br />

b+b-QQ<br />

erit. Nulia igitur Medii den&ate movebitur krojeaile in Parabola,<br />

uti ohm demonfiravit GaZiZaz~s, $E, I.<br />

.Exempl. 3. Sit linea AGK Hyperbola, Afymptoton hahens<br />

AIX plano horizontali AK perpendicularem j & quzratur Medii<br />

denfitas qua2 faciat ut soje&ile moveatur in hat linea.<br />

Sit ik!X Afymptotos nltera, ordinatim applicator: ZIG prod&&<br />

Occurrens in Y, & ex natura Hyperbola, re&angulum .XY in T/G<br />

dabitur. Datur autem ratio DN ad YX, k propterea datur etiam<br />

r&-angulum ZaNin VG. Sit illud 66 ; Sr complete parallelogrammo<br />

fDNX,2& dicatur BAT a9 BID 0, ..2V X 6) & ratio data P’Z adZX<br />

ye1 DA? ponatur effe F. Et erit iD AV aequalis a-o, VG xqdis:<br />

66<br />

-3 ,VZ zequalis Ea -o9 SE G.D feu NX-V.Z-F’G Z-<br />

a -0-<br />

w<br />

66<br />

efolvatur terminus - in ferjem<br />

ca-0<br />

z:qu.a-<br />

term&<br />

nus kcundus Fo -- - o ufufpandus efi pro Q, tertius cum figno<br />

aa<br />

bb 66<br />

mutato ;z?-02 Pro oz9 & quartus cum figno etiam mutato FeO3.<br />

--<br />

m bc, bb 66<br />

pro so3, eorumque coefficientes -- -, - &z tiribendae Punt<br />

iv aa a3<br />

o f;l&o prodit lmedii denfitas<br />

ut


%Z m 2mbb 6”<br />

---CW---~~<br />

hunt ipfarum X Z Sz 22’ quadrata.<br />

n n<br />

tia autem inFenitur in ratione ad gravirateln ~~,uam habet 3 XTad<br />

2 TG 8-z velocitas ea efi quacum corpus in Parabola pergeret verti-<br />

tern G, diametrum DG,& latw reQum xTPu” YG habente. Pona-<br />

tur itaque qnod Me&i de&ares in locis fingulis G fint reciproce<br />

ut difiantk XT, quodque refifientia in loco aliquo G fit ad gravitatem<br />

ut 3XTad iTG; & corpus de loco A, jufia cum velociefcribet<br />

Wyperbolam illam A G I


ollark:, prinlo, ii refifientia ponatur ut velocitatis V dignitas<br />

S<br />

libct V’ prohibit denfitas hledii ut ----+ x sv-l’<br />

q2 JHT I<br />

Et propterea fi Cwva inveniri potefi ea lege UE data fLIerit:<br />

CpEt-<br />

ratio<br />

ad I+QQI”-’ : corpus move-<br />

bit& in hat C&va in uniformi Medio cum refifientia quz fit ut<br />

velocitatis dignitas V ‘. Sed redeamus ad Curvas fimpliciores.<br />

Qoniam nlotr~s non fit in Parabola nifi in Medio non refiitente,<br />

in Hyperbolis vero hit defk-iptis fit per refiitentiam perpetuam;<br />

per@icuum elk quod Einea, quam projeBile in Medio uniformiter<br />

Aitente defcribir, propius accedit ad Hyperbolas hake quam ad<br />

Parabolam. Efi utique linea illa Hyperbolici generis, fed qux<br />

circa verticem magis difiat ab Nymptotis; in partibus a vercice<br />

remotioribus propius ad ipbs accedic quam pro ratione Y perbolarum<br />

quas hit defcripfi. Tanta vero non efi inter has & illam<br />

diflkrentia, quin illius loco pofinr h3e in rebus pra&icis non incommode<br />

adhiberi. Et utiliores forfan future fiint hz, quam<br />

Hyperbola magis accurata & fimul magis compofita, Ipfa: vero<br />

in ufurn ilc deducentur.<br />

Compleatur parallelogrammum XTG T, & re&a GT tanget<br />

Hyperbolam In G, ideoque denfitas Medii in G: efi reciproce ut:<br />

GTy<br />

tangens GT, & velocitas ibidem ut d,-<br />

GV’<br />

refifientia autem ad<br />

21212-j-272<br />

vim gravitatis ut G.57 ad<br />

723-z GK<br />

Proinde iii corpus de loco A’kcundum reQam AH proje&um<br />

dekribat yyperbolam AGK, 8c AH prod&a occurrat .taijrmytoto<br />

MX !n II, acaque A..I eidem parallela occurrat alteri Aiymp-<br />

.xoto &?X In I: errt Mediidenfitas in A reciproce ut A?$,‘& ear-<br />

goris velocitas ut +Js, ac refifkntia ibidem ad gravitatem ut


R‘ ATHEMA 24; .<br />

“Reg. I, Si fervetur tu’m Medii denfitas in A, turn veIocitas qua- LIBER<br />

dum corpus projicitur, & mutetur anguhs NAH; manebunt ion. SECVND WC.<br />

gitudines AH, AI, HX Ideoque ii longitudines ilk in aliquo<br />

ca.fu inveniantur, Hyperbola deinceps ex dato quovis angulo NAM<br />

expedite determinari potefi.<br />

Reg. i. Si firvetwr turn angulus A? AH, turn Medii denfitas<br />

in A, & mutetur velocitas quacum corpus projiciturj fkrvabitur<br />

Iongitudo AH, & mutabitur AI in duplicata ratione velocitatis<br />

reciproce.<br />

Reg. 3. Si tam angulus--2VtiH: quam corporis velocitas in A,<br />

gravitafque acceleratrix fervetur, & proportio reIXentia: ,in A ad<br />

grauitatem motricem augeatur in ratione quacunque : augebitur<br />

proportio AH ad AI in eadem ratione, manente Parabok late-<br />

re reQo, eique proportionali longitudine AW<br />

AI j 8~ propterea minzletur<br />

AH in eadem ratione, & AI minuetur in ratione illa duplicata.<br />

Augetur vero proportio refifientia ad pondus, ubi vel gravitas<br />

fpecifica fub azquali magnitudine fit minar, vel Medii de&<br />

tas major, vel refifientia, ex magnitudine diminuta, diminuitur in ’<br />

minore ratione quam pondus,<br />

Ii<br />

\ Regq


~apJTx fir ~~~~~~~ i,X$j<br />

.&%g, ‘8..Invemis longitudinibus i4.E& kTX; ii jam defideretur LIB PR<br />

pofitio fe&z d~H,,fice:ndufi~ quam ProjeEtike, data illa cum veloci- SE~‘UND vs.<br />

tate mifim, incidit in :p’un&wm quodvis K: ad pun&~ JTI’ & f<<br />

erigantur reQa AC, IC F horizonti.perpendiculares, -quarum .,zI c<br />

deorfim tendat, & aquetur ipfi AL L?u fHX. Afymptdris /Z K,<br />

I centroque A & intervallo &g.defcribatur Circulus fkans<br />

perbolam illam in pun&o 29 ;. $G ~ProjeMe ficundum re&arn A B<br />

emiffim incidet in pun&urn K. .J& E. I. Nam pun&urn r;H ob<br />

datam lon itudinem AN, locat-ur alicubi in Circulo defcripto. A-<br />

gatur C HP occurrens ipfis A.&I: & .K+F, ilh in E, huk in 3; & ob<br />

parallelas CH, MX & zquales AC, 341, erit R E azqualis AIM,<br />

sr: propterea etiam aequalis KN. Sed CE efi ad AE ut FH ad<br />

K L\r, 8-r propterea C E & FH aquantur. Incidit ergo pun&urn<br />

.Ef in Hyperbolam Afymptotis AK, KF defcriptam, cujus conjugatal,tra+t.per<br />

pun&urn &; atque adeo reperitur in communi in..<br />

terMti’oneHyperbolaz hujus & Circuli dekripti. &E;,B. Notandum<br />

efi autem quod haec operatio perinde k habet, five reQa<br />

A .K N horizonti arallela fit, five ad horizontern in angulo quovis<br />

inclinata : quo 9 que ex duabus interfe&ionibus k& H duo prodeunt<br />

anguli .ATA.E?” NAHj fi~od in Praxi mechanica fiifficit<br />

Cir-


f++ PHILOSOPHIC WA<br />

IJE hrO,T u Circulum femel dekribere, deinde regulam interminaram Cff ita:ap<br />

coup *I{ vhi plicare ad pun&urn C, UC ejus pars FH, Circulo’& re&z FK interje;<br />

&a, aqualis fit ejus parti CE inter pun&urn C & re&am JlK fit%,<br />

Qux de Hyperbolis di&a funt fa- I<br />

tile applicantur ad Parabolas. Nam ^_<br />

fi X&GE Parabolam defignet quam<br />

re&a XFtangat in vertice X, fintque<br />

ordinatim applicatx JA, YG ut qux&<br />

Jibet abfciciffarum XI, XT dignitates<br />

Xl”,XY”j aganrur X’Z GT, AH,<br />

quarum XTparallela fit YG, Sr GT,<br />

A W Parabolam tangant in G &A: St<br />

corpus de loco quovis A, fecundurn<br />

rettam AN produQam, jufia cum R<br />

velocitate projeRum, defcribet hanc<br />

Parabolam, fi modo den&as Medii,<br />

in Iocis fingulis G, fit reciproce ut<br />

tangens G T. Velocitas autem in G ea erit quacum ProjcQile per..<br />

geret, in fpatio non refifiente, in Parabola Conica vertic;mGG+ dia-<br />

.<br />

metrum YG deorfim produktm, & latus reQum<br />

i%=i& YG<br />

habente. Et refiitentia in G erit ad ,vim gravitatis ut G T ad<br />

3” - 3 ’ YG. Unde TX NAK lineam horizontalem defignet, &<br />

12-2<br />

manente turn de&ate Medii in A’, tdm velocitate quacum corpus<br />

projicitur,. mutetur urcunque adguius AL&H; manebunt ldngitudines<br />

AH, AI, HX, St inde dater Parabolk vertex X, & pofitio<br />

re&az XI, & fumendo YG ad IA ut XV’ ad Xj’, dantur omnia<br />

Parabok. pun&a.G, per qua= Proje&ile tranfibit, .<br />

: s .,<br />

: ,^<br />

1. -,<br />

.,<br />

‘: .. ‘. ” ><br />

“$’ .- . :’ ‘.’ ‘,,, ~, ,, ’ I’ (.” i<br />

. i. ,.<br />

.’<br />

I. .‘:<br />

’<br />

SECTI’<br />

, . . ^. _:<br />

. . .’ .,,‘_, ,,


PHQ”POSi~IQ XI. THEOREMA WI.<br />

Si Corpori reJ/%tur partim in ratione rvelocitatts J partim in VGP<br />

locitatis ratione duphcata, &Y idenz lola vi ir$ta in Media Ji-:<br />

milari mocuetur, J.hantur autem tempora in progre$one Arithmetica<br />

: quantitates velocitatibus rehroce propbrtionales, dat&<br />

guadum &an&ate a&e, erunt<br />

Centro C, AcymptotiS ,rclkangulis<br />

CA2)d & CEZ, defcribatur<br />

Hyperbola B EeS, ck Aijrmptoto<br />

CH parallels iinr AB, I> E,<br />

de. In Afymptoto C 53 dentur<br />

pun&a A, G: Et G tempus exponatur<br />

per aream Hyperbol+am<br />

AB E 59 uniformiter crefcentem ;<br />

dice quad velocitas exponi gotefi<br />

per longiiudinem ‘D F, cujus reciproca<br />

G I) una cum data - CG co‘mhonat<br />

longitudinem C”D in progreflione, Geometrica crefcentem.<br />

Sit enim areola D E ed datum temporis incrementum qflam<br />

minimum, & erit ‘Dd reciproce ut fD E, adeoqye dire&e ut<br />

.’<br />

C2). Ipfius autem & decrementurn, quod (per liujus Lem,w]<br />

eit ‘Dd . CD guCGtG-],.id &., ut I;. CG‘.:<br />

G’L)q,erlt ut GcDq<br />

G ‘” gp-jy’<br />

02<br />

Qitur temporedl3 E D per additionemdatarum particularum E,D de3<br />

-<br />

uniformiter crefcente, decrefiit -!--in ‘eadem ratio@ cum veloci;<br />

62) I_... “..:, . > ,..’ -i<br />

tare, Nam decremer-+um velocitatis efi’ut refiftekia, hoc @-(per:<br />

Hypothefin) UT fimma ,.du?rum qu+ntiFatum, .quarurn*. uea e:ei:t<br />

‘\ 1


decrementurn eif ipfius GD, erit reciproae’ UC &ZI, adeoque. &-<br />

r.lLroen<br />

reBe ut C”D, hoc aft, ut fumma ejpfdem.GfD &. longitudinis datz SL~~~D~J~*<br />

c’ G. Sed velocitacis decrementum, rempore fibi reciproce pro&<br />

portionah, quo data fpatii particul;-2 ‘DdeE d&rrbit,urj & ut reh<br />

fiitcntia 8r tempus conjun&im, id e@, dire& ut fknma duarum<br />

quantitatum, quarum una efi ut velocitas, a,ltcra ut vel~citatjs qua*<br />

dratum, & inverfe LIC velocitas; adeoque dire&e ut iiimma duatum<br />

quantitatum, quarum una dacur, altera efi ut velocitas. Zgitur decrementum<br />

tam velocitatis quam linez GfD, efi ut quarltitas, data<br />

& quantitas decrefcens conjunQim, &z propcer anaIb&a decrenlenra,<br />

analogzz femper erunt quantitates decrekentes: nimirum velociras<br />

& linea G’D. & E. D.<br />

C’orol. I. Igitur ii velocitas exponatul?per.lol)gitudinemlGI), $atium<br />

deh-iptum wit UC area Hyperbolisa D&‘&F,<br />

Cuy& 2,. Et. fi, utcunqueaffumatur pun&umk A, invenietur pun-.<br />

Qum G0 capiendo.G 62 ad G II, ut elt’ velocitas fub initio ad veL<br />

l+itarem pofi fpacium: quodvis X SE B defcriptum. Invent0 autern,<br />

puntio G;19 datur fpatium;cx data- velocit-ate, & contra.<br />

Cor~ll; 3 Uhd~:cum, per Prop: x13 dctur.,velocitas ex dato ternpore,,<br />

Q- per hanc Bropofitionam det.ur @atium ex data velocitatc i j<br />

dabitur fpatium ex dato ternpore: & conera,<br />

PROPOS1TIO XIII. THEOR.E.MA X.<br />

CL& I. Fonamus primo quod GOI’~LIS afiendie, centroque 2) &<br />

fimidiametro quovis “D B defcribarur Circuli quadrans BE TF, &<br />

per kmidiamctri ‘53 B terminum 23 agatur infinita BAT’, kmidiarnetro,YI<br />

F parallela, In ea detur pun&urn&, 6~ capiatur kegmen.=<br />

tum.~Y? velocitati proportionale. Et cum refifientia: pars aliqua fi.s<br />

ut


i48<br />

Th MOTU ut velocitas 82 pars altera ut<br />

“C)Rp * n *” velocitatis quadratum, fit refifientia<br />

rota in T ueAT pad<br />

+2 BAT. Jiingantur 23 A,<br />

59 2” Circulum fecantes in .E<br />

ac T3 & exponatur gravitas per<br />

I) A qwd,ita ut fit gravitas ad<br />

refil?entiam in T ut ZlAq ad<br />

ATq +zBAT: & tempus<br />

afi2enfis omnis futuri erit ut<br />

Circuli k&or ED TE.<br />

Agatur .enim 23 Vg, ab-<br />

cpwd.<br />

Proinde area 23 T ,.$$ ipfi T $ proportionalis, ec ut 2) Tqzr~d;<br />

& area I) TK (quz eft.ad aream ‘D T ut DTg ad DTq)<br />

ef\ ut.datum 59 2-q. Decrefiit ,igitur area E % T aniformirer ad madum<br />

temporis futuri, per fibdu&ionem datarum particularumD Tr,<br />

st propcerea tempori afienfus fitturi progortionalis efh, ,$2&E, B..<br />

Cujt 2. Si veloci-<br />

:ras in aCcenfh corporia<br />

exponatur per<br />

Iongitudinem AT<br />

UC prius, 4% reMen-<br />

-tia ‘ponatur effe ut<br />

ATq+-dA5?, &<br />

ii vis gravitatis mi- B<br />

nor fit -quam qw per<br />

‘53 Ag cxponi pof--<br />

St j capiatur I3 9 e-<br />

~LIS longitudinis3 ut<br />

fit A B,,q - BI) q<br />

gravitati proportloride,<br />

fitquc 9 Fip%<br />

m B perpendicularis<br />

1<br />

or xqualis, & per vyticem 8’ ckfkribatur RIP<br />

ycrbola FTYE cujus femidiametri conJu&atz fint 2) B. & 2, fi<br />

.quzque kcet D L! in E, St 23-T, FZ3-R in T & F; & cnt tern us’<br />

.arcenfus futuri ut H7ypcr-bolg Ikeor TYMJo ‘- Np am


P R I: N G I P I A M A T Id E b:i A ‘E” I c, A. zq 3<br />

‘&Jam vclocitatis decrementurn TRY in data ternpork prticula ~ruit.~<br />

f&urn, eat ut fumma rcfidtentiz A ‘B 4 -+ 2 BA ‘P & grawratis SECuNUr.f’<br />

ABE -B2,q, id et?, ut BF’<br />

ad aream ‘D Y-‘g UI '13 Tq ad ad 2) F demirtatur<br />

perpendiculum GT9 UC<br />

mque GfE,g ad B”a)q &<br />

C&are cum area ‘59~P~fit ut 5?,$& id efi, UC B’Pq-&Ug;erit<br />

area Tl TY ut datum 53 Pq. Decrefcit igitur area ED 7’uniformiter<br />

hgulis temporis pnrticulis aqualibus, per f&bdu&ionem par-<br />

.ticularum totidem datarum 59 TV, & propterea tempori proportion&<br />

eB. sE.2).<br />

Ca/; 3, Sit A T’ velocitas in dekenfu corporis, EC A Ppq + 2 B&F<br />

refifientia, & B 2) 4 - A B 9 vis gravitatis, exifience angulo 3) 43 A<br />

x&to. Et ii centro 59, vertice<br />

principali .B, dekribatur Hyperbola<br />

re&angula B E TV<br />

kcans produ&as 1) A, 9 T &I<br />

‘fi!?Rin E, T& Vj wit Hyperbolz<br />

hu’us k&or YDET ut<br />

tempus de l cenks.<br />

Nam velocitatis incremhum<br />

T & eique proportionalis area<br />

23 YP 2, efi ut excefliis gravitatis<br />

Cupra refifienciam, id efi, LIP<br />

BDq-ABq-a&W-ATq<br />

fiu BDq-BTg. Et area<br />

59 TV efi ad aream ‘BT &ut<br />

DTq ad ‘DTq3 adeoque ut<br />

GTg feu GDq-BTlq ad<br />

BTq ucque G”Wq ad BDq<br />

hk divifim ut BI)q ad BDg -<br />

fit ut BDq-B*Pq, erit area<br />

igitur area ED T uniformiter<br />

bus, per additionem totidem dat<br />

eerea tempori defcenfus propor<br />

C20roZ. Igitur velocitas AT eR ad velocitatem quam corpus tern--<br />

pore E 2) T, in fjpatio non refiflente, afcecendendo amittere veI de*<br />

tiendendo acquirere poffet, ut area trianguli DAT ad aream [em<br />

&or& ten tro 9, radio DA, angulo A 2l T defcripti 5 ideoque ex<br />

data eemporc datur. Nam velociri in Media non refifiente, tempori


q2ews pop&r, dim qmd @ntdm clfc~s~f? vel deJceuJti defcriptgm,<br />

~$7 fdt di$Svw&z me& per qhmz tempos exponitur, e$$ ared CUjfiJdam<br />

‘izTterz7d.f pie dugetw vel diiminuitur in progrefimze Am<br />

&hneticu;<br />

ji vire.r ex re/37entid & grazlilate compoJzt02 J&<br />

2ffar~tflv in pmpefione Geomtricu.<br />

.<br />

lCapiatur AC (in Fig. tribus ulcimis,) gravitati, &C.&Ii: refi-<br />

I”renti3e proportionalis. Capiantur autem ad eaiaem partes pun-<br />

&i A fi corpus defcendit, aliter ad contrarias. rigatur A6 qua<br />

fit ad DB ut DBq ad 4BAC: & area A6NK augebitur vek<br />

diminuetur in progrefflone Arithmetica, dum vires CK in progreGone<br />

Geometrica fiimunturr. Dice igitur quod dihntia carpork<br />

ab ejus altitudine maxima fit ut exceffus arez Ab .A?K filpra<br />

aream ‘23 E T.<br />

Nam cum AK fit ut refiitentia, id 4, ut n’P4 -f-~Bn73;~<br />

affimatur data quxvis quantitas 2, & ponatur -,4 I< zqualis.<br />

ATq-+-z&AT<br />

z.<br />

; 8~ (per hujus Lemma II.) wit ipfius AK mow<br />

arex ~$b NK momentum K L 0 ..iV aquale.<br />

2J3~cpx~O few<br />

z.<br />

BT@BDcd.<br />

zzxc•~xA•3<br />

•<br />

CaJ I. Jam G corpus ai’cendit, fitque gravitas tat li;‘Bq +BDg;<br />

exifienre BE T’ Circwlol, (in Fig. Cai: I, Prop. xxlr.) linea A C;<br />

quaz gravitat.i proportionalis eff, erit JfBg+Bq - .z--- , & 2, Tg feu.<br />

ATq+aBAF’+A.Bq+BDq<br />

eritA.XX,Z+ACxZi‘eu:<br />

CK x 2 ; ideoque area D 1 Y erit ad aream D S;P,gut D Zq vel<br />

tDBg ad CICxZ.


PIUNCIhd MA?3%3&4?XSl. 25 I<br />

Ckf. 2. Sin corpus akendit, SC gravitas fit ut A&q--B‘Dq ~~~~~<br />

liinea AC ( Fig. CaC 2. Prop. xIxr ) erir ABq-/Dg,, & 2, Tq SECUPI’UUi-<br />

wit ad TI’Pq ut “n4;q feu DZ3q ad BPq-2323q fiu A*F’q +<br />

%BIL4~3~1~~plP-,‘~Y,ide~,adnJcxz-.}-nCxzreuC/~x%.<br />

Edcoque area D TYeriE ad aream 53 *f qut D Eq ad CKXZ.<br />

C&f. 3. EC eodem argumenso, fi corpus dckendir, (k propterea<br />

gr”Vlt”s ii t ut B 52 q - kBq, klinea AC (Fig, CaL3. Prop. prxced,)<br />

.pquetur Bm4-nBq -.<br />

z<br />

eric arca 53 TV ad aream ‘53 P gut I) Bq<br />

ad 6: K x ri: : kit fupra.<br />

Cum igitur are32 ill32 fimper ht in hat ratione; fi pro area<br />

2) T VP qua momentum temporis Gbimet ipfi femper xquale exponitur<br />

, kribatur determinatum quodvis re&ngulum, puta<br />

BDxm, erit area 2,T& id efi, tB’Dx’P$; ad BBxm ut<br />

~KxZadBD.<br />

Atque inde fit ‘P g x B D czh. zq uale<br />

2BDX?.?ZXCKX 2 , & arex Ab N K momentum XL, 0 N h-<br />

perius inventurn,<br />

fit BTxB”Dxm AB e Auferatur are2 BET mo-<br />

mentum 2, TV fiu B 2) x rn, 8~ refiabit<br />

Efi ipi-<br />

tur differentia momentorum, id ef?, momentum difkrentk area-<br />

ATXBDXM<br />

BDXH2<br />

rum, zqualis A-B- 5 & propterea (ob datum AB ><br />

ut velocitas AT, id eh ut momentum fpatii quod corpus afcendendo<br />

vei defcendendo dekribit. Ideoque dicerentia arearum<br />

S; Qatium illud, proportionalibus momentis crefcentia vel decrefcentia<br />

Sr iimul inciplentia vel fimul evanefcentia, funt: proportionalia.<br />

SE. 22.<br />

Co&. Hgitur ii longitude aliqua V fumatur in ea ratione ad duplum<br />

longicudinis Mb, qurr oritur applicando aream (m E Tad B 53,<br />

quarn habet linea CD A ad lineam D E j I-patium quod corpus afcenfu<br />

vel dekenh toto in Media refifiente defcribit ) erit ad fpahn<br />

quad in edio non refiitente eodem tempore defcribere poffet,<br />

ut arearum illarum differencia ad BDXV”<br />

$ ideoque ex dato tem-<br />

pore datnr. Nam Qatium in cdio non refi fiente elt in duplica$a<br />

ratione temporis, five Ill & ob data% B & A&<br />

B


BDXV”<br />

,Equdis igitur eft area quam minima - differentiz quam<br />

4AB<br />

minimz arearum TI ET & Ab NK. Unde cum fpatia in Medie<br />

utroque, in principio defcenfh vel fine afcenfus fimul deficripta<br />

accedunt ad zqualitatem , adeoque tune funt ad invicem ut area,<br />

BTDXV’ & arearum 22 ET & AbNICdifFerentia; ob eorum ana-<br />

4AB<br />

Ioga incrementa necefi efi ut in ayualibus quibukunque tempo-<br />

ribus fine ad invicem ut area illa BDxV’ & arearum 53ET &,<br />

*,, A-.<br />

4AB<br />

A b AC&C diEerenria. S&E., a>.


ClHA MATHEMATICA. 253<br />

LIRER<br />

SECIJNDUS.<br />

L E M R/f A<br />

III.<br />

$t I? QR r Spiralis qu& j2ce.t radios omnes S I?, S Q, S IX, &c.<br />

in qualibus m&is. Agatw reBa P ‘I’ HUB tangat eandem in<<br />

punffo quocvis P, Jec*etque radium S Cp, in II: ; & ad Spiralem<br />

ereffis perpendiculis I? 0, Q 0 concurrentibus in 0, jungatur<br />

S 0. Dice qzaod Ji pm8a P & cawedant ad invicem & coednt,<br />

arzgulus~ PS 0 ervadet reEus, & ultima ratio re@anguli,<br />

‘I’ QX LPS ad P Qquad. erit rutio quahtatis.<br />

Etenim de angulis re&is 0 T 2, O&Z-? hbducantur anguli<br />

azquales 5 ‘I’& SRIz, Sr manebunt anguli lrquales 0 T S, 0 RSO<br />

Ergo Circulus qui tranfit<br />

per pun&a 0, S3 T tranfibit<br />

eriam per pun&urn 2:<br />

Coeant pun&a T & L&<br />

& hit Circulus in loco co- p<br />

itus 5? gtanget Spiralem,<br />

adeoque perpendiculariter<br />

fixabit: reQam 8 T. Fie.t V<br />

igitur 0 T diameter Circuli<br />

hujus, 8z angulus<br />

0 ST in kmicirculo re.-<br />

I &us, J&E. 9..<br />

Ad 0 T demittantur perpendicula RD, SE, .st linearum rationes.<br />

ultimze erunt hujufmodi : r.$ad T 13 ut 576’ vel TS. ad, ~,!3,<br />

ku zT O.ad 2,T.S. Iterm T 59 ad TR ut T xad 25? 0. Et elk;.<br />

3equo perturbate IRad T & wt T 2 ad zT S. Unde fii3 2S;<br />

aqyale fz”g~ zT& 2& E. ‘II.<br />

pZg.Clp@2.


DE Moru<br />

ConPonu.+l<br />

Poilantur qux in fuperiore Lemmare,~& producatur S&ad Y,<br />

it iit SYxqwIis ST>, Tempore quovis, in Media refifiellte, de-<br />

Cribat cot-pus arcum quart minimum ‘P,G$ ck rempore duplo arcum<br />

~lu;lm minimum Y R j Sr decrementa hurum arcuum ex refifientii<br />

oriunda, five defe-<br />

&us ab arcubus qui in Medio<br />

non refiltenre iii&m<br />

tenlporibus dcfcriberentur,<br />

erunt ad iavicem ut<br />

quadrata temporum in P<br />

quibus generantur : EfB<br />

itaque decremcntum arcus<br />

T g pars quarta decre- -v<br />

mcnti arcus F’ K. Unde<br />

etiam, fi are22 ‘FS 2 a-<br />

qualis capiacur area $&J?r,<br />

erit decrementurn arcus<br />

“T $Z?+ zquale dimidio lineola R P ; adeoque vis refifientiz & vis tentripeta<br />

hnt ad invicem ut line& $ R I & TRquas fimul generant.<br />

Qloniam Gs centripeta, qua corpus urgetur in F, efi reciproce nt:<br />

J’fiDq, EC (per Lem. X* Lib. I,) lineola T&& qua: vi iIIa generatur; ~8<br />

in ratione compofira ex ratione hujus vis & ratione duplicaea tern--<br />

poris quo arcus fp S?+ deli-ribitur, (Nam refifientiam in hoc c&,<br />

!.It infinite minorem qufm vis centripeta, negiigo) erit TRx.Jpq<br />

Id efi (‘per: Lemma oovlffhum) $rPa >(S*P, in ratione d+licata<br />

tempo& adeoque ternpus eti ut ~2 x +LP.P~; k corporis veloci-<br />

tas, qua arcus a> &illo tempore defcribitur, UC 2;‘2<br />

Tg?buT<br />

SV&, hoc efi, in iilbduplicata ratione i@ius SP recipkce. Et ii-<br />

pylili argumetlto 2 velocitas qua arcus g&h! d&‘cribitur3 efi in fuCub=<br />

duplicata<br />

i-ix


PRIPdCIPIA MATHEMATICA. 2’5.5<br />

duplicata ratione iplius S&rcciproce. Sunt autem arcus illi fpg LIBER<br />

& 2-R ut velocitates dekriptrices ad invicem, id tit, in fubdup]i.. secu~nu~*<br />

cata ratione S,GLad ST, five ut Sqad JST xS$& &C ob xc~ua-<br />

]es angulos ST L& S g r & trquales areas T J ,$$ $-&Sr, efi arcus<br />

T gad arcu!-Rr ut SQd ST. Sumantur proportionaliunl<br />

conkquentium dlflerentiaz, & f~er nrcus T,!q ad arcum ,527 ut S2<br />

ad ST -4STxS& reu $V&?& nam pun&is ‘P lk &coeuJ~cibus,<br />

ratio ultima S 23 - d S -2 x S 9\ ad t Yx fit aqualitatis.<br />

Quoniam decrementurn arcus I-‘& ex refifktltla oriundum9 five<br />

]lujus duplum Rr, efi ut refifie_ntia & quadratum remporis con-<br />

Kr<br />

jun&m; erit refificntia ut<br />

Erat autcm T gad R r,<br />

T&XJ’T’<br />

Rr<br />

:v.g<br />

ut Sgad $Y& & inde<br />

fit UtTRxJNT xJ.gfive<br />

fOS<br />

‘lt OT xSTq’<br />

coincidunt 3 8~<br />

‘Ygq x 3’*P<br />

Namque pun&is T & &oeuntibus, ST & Sg<br />

angulus T Yg fit retius; Gt ob fimilia triangula<br />

fit Tg ad f Vg ut ObT ad : OS. Efi igitur<br />

refifientia, id eftj in ratione denfitatis Medii in T<br />

& ratione duplicate velocitatis conjun&im. Auferatur duplicata<br />

ratio velocitatis,<br />

I-’ ut<br />

OS<br />

O~%ST’<br />

nempe ratio S .-.L.-<br />

CT, & manebic Medii deniitas in<br />

Detur Spiralis, Sr ob datam rationem OS ad<br />

OT 9 denfitas Medii in T erit ut &. In Media igitur cujus<br />

denfitas eft reciproce ut diftantia a ccntro ST, corpus gyrari potefi<br />

in hat Spirali. $-&E. I).<br />

Coral. I. VeIocitas. in loco quovis T ea femper efi quasum cord<br />

pus in Media non refiltente gyrari pot& in Circulo, ad eandem a<br />

centro difiantiam ST.<br />

OS<br />

Carol. z, Medii denfitas, ii datur difiantia ST, efi ut aT, fin<br />

OS<br />

difkantia illa non datur, ut O by x S,P. Et inde Spiralis ad quam-<br />

libel: Medii denfitatem<br />

aptari potek<br />

Cmd, 3. Vis refifientk in loco quovis T, ‘efi ad vim centripe-.<br />

tam


S( fp $)!, reu :O J” & 0 “P. Data iglkr Spirali datur prop,ortio re-<br />

Gtt-en& ad vim centripetam, & vfceverl;l ex data illa proportiork<br />

&cur Spinalis,<br />

CoroL 4. Corpus itaque gyrari nequit in hat Spirali, nifr ubi vis<br />

refiflentis minor ef+ quam dimidium vis centripetz Fiat refifientia<br />

~qualis dimidio vis centripetk & Spirahs conveniet cum linea<br />

re&a FS, inque hat reOa corpus defiendet ad centrum:, ea cum<br />

velocitate quz iit ad velocitatcm qua probavimus in iirperioribus<br />

in caiil Parabola (Theor. x, Lib, I,) defceniirm in Medio non refifiente<br />

fieri, in Tubduplicata ratione unitatis ad numerum binarium.<br />

Er ternpora defcenfils bit erunt reciproce ut velocitates, atque<br />

adeo dantur.<br />

Cowl. f. Et quoniam in ;xquaIibus a centro difiantiis velocitas<br />

eadem efi in Spirali ‘P&-R atque in re&a ST, & longitude Spiralis<br />

ad longicudineni re&i-le T S efi in data ratione, nempe in I’<br />

ratione. 0 TJ ad 0 S; tempus defienks in Spirali erit ad tempus<br />

de&n&s in reQa ST in eadem illa data ratione, proindeque<br />

datur.<br />

CovaA 6. Si centro S intervallis duobus quibufcunque datis dekribanrur<br />

duo Circuli j & manentibus hike Circulis, mutetur utcun=<br />

que angulus quem Spiral& continet cum radio T S: numerus revolutionum<br />

quas corpus intra Circulorum circumferentias, pergendo<br />

in Spirali a circumferentia ad circumferenriam, complere pore& eR<br />

utTS =, five ut Tangens anguli illius quem Spiralis continet cum<br />

OP<br />

radio T 5’; tempus vero revolutionurn earundem ut -3 id efi? UP<br />

OS<br />

Secans auguli ejuidem, vel etiam reciproce ut Medii denfitaa.<br />

Coral. 7, Si corpus9 in Medio cujus den&as efi reciproce ut die<br />

fiantia locorum a centro, revolutionem in Curva quacwque AE B<br />

circa centrum illud fecerit, & Radium primum AS in eodsm an.=<br />

gulo ‘fecuerit in 23 quo prius in A3 idque cum velocitate qua: fuerit<br />

ad velocitatem Guam primam in A reciproce in fubduplicata<br />

ratione diitantiarum a centro (id cfi, ut AS ad mediam proportionalem<br />

inter AS & B 5’) corpus illud pergec innum+<br />

ras confimiles kevolutiones 23 EC, &I GD &c. facere> & i+nterf&.<br />

&ionibus


&ionibus difiinguct Radiu<br />

9oncinue proportionales.<br />

S in par&s AS, B S, GS,<br />

evolucionum wro cempora<br />

perimctri Orbitarum A E B, BFC, CG’D, kc. dire& & vctocim<br />

tatcs in principiis /?‘,B, C, invcrk j id cR9 ut JZJ$, Sfi, CG. Atque<br />

ternpus roturn> quo corpus perveniet ad cc~~crum, crit ad tcmpus<br />

revolutionis prima, ut .(umma olnnitrm continue proportionalium<br />

AS+, J?L3& CS.; pergentium ia infinitum, ad tcrminurn primumASk;<br />

id cfi, ut terminus ilk prhusRS~ ad difkrcntinm duorum<br />

prirnortu~ A $k - BSk, five ut -Q’S ad .L?B quam proximc,<br />

Undc tcmpus illud totum expedite invcnitur.<br />

Cool. 8. Ex ‘his ‘ctiam prxtcr ropter colligcrc licet motw cord<br />

porum in Mcdiis, quorum den P ~tas aut uniformis efi, aut alliam<br />

quamcunqtxe $g3n &ignatam obfirvat, CIcntro Sj intervallis continuc<br />

proportwnalibus SA, $23, SC, kc. defcribc Circulos quoticunque,<br />

& fhtuc tcm us revolutionum intcf pcrimctros duorum<br />

qworumvis ex his Circu P is, in Mcdio dc quo c imus, cfk ad tcmpus<br />

tevolationwn inter coiilcm in Mcdio propo ? Ito> ut Mcdii propod<br />

Gti dcnfiras mediocris inter has Circulos ad Mcdii, dc quo cgimus,<br />

de~fitatcm mcdiacrcm htcr eofdcm quam proximc: Scd & ix1 cam<br />

I;rcm quoque rationc cfi Sccamcm anguli quo S iralis przfinita,<br />

an Media de quo cgimuss kcat radium ~7s~ ad 5) ‘ecantClpr gyg.Ji<br />

l-41 guoi


n F &IoTv quo Spiralis nova kcat radium eundem in Media propofitd : Atf;on.<br />

p 0 KU :L que etiam ut funt eorundem angulorum Tangentes ita effe numeros<br />

revolutionurn omnium inter Circulos eofdem duos quam proxime,<br />

Si hz:c fiant paflim inter Circuios binos, conrinuabitur motus per<br />

Circulos omnes. Atque hoc patio haud difficulter imaginari pofIimus<br />

quibus modis ac temporibus corpora in Nedio quocunque regulari<br />

gyrari debebunt.<br />

Curd. 9, EC quamvis mows excentrici in Spiralibus ad formam<br />

Ovalium nccedentibus peragantur ; ramen concipiendo Spiralium<br />

illarum fingulas revoluctones i&dem ab invicem intervallis difiare,<br />

iifdemque gradibus ad centrum acceder-e cum Spirali fuperius dekripta,<br />

intelligemus etiam quomodo motes corporum in hujufmodi<br />

Spiralibus pcragantur.<br />

Demonfiratur eadem methodo cum Propofitione fiuperiore.<br />

Narn fi vis centripeta in P fit reclproce .ut difkantizl: ST dignitas<br />

qwhbet S ‘P-4-~ cujus index efi YZ + 11 j colligetur ut fiipra,<br />

quad tempus quo corpus dekribit arcum quemvis P 2 erit ut<br />

!P RX ST?,<br />

Al=<br />

& relifientia in T ut<br />

Tg&GST~’<br />

I-p2XC.Q<br />

-‘i.nxos<br />

adeoque ut<br />

, hoc efi, ob datum I<br />

OTxJ’Tnct1<br />

O’P<br />

I, rekiproce<br />

ut ST ‘S-I. Et propcerea, cum velocitas fit recipioceut STQ”,<br />

denfitas in T erit reciproce u.t S-P.<br />

Cowl. I. Refiitentia eit ad vim centripetam, ut I -. t a ~0 I@<br />

ad CIT.<br />

Curol. P, Si vis centripeta fit reciproce ut STcz.4, erit I --$a==~;<br />

adeoque refrfientia & denfitas Medii nulla erit, ut in Proyofitione<br />

Plona Libri primi.<br />

Coro~. 3, Si vis centripeta fit reciproce ut dignicas aliqua radii<br />

STcujus index efi major numero s9 refiftentia affit’ma.tiva in negal<br />

tivam muta bitur.<br />

Scbls-


Caterurn h-Xc Propofi tio<br />

ter &da fpeflm 3 intelligen- lunt ae mow corporuln acico par-<br />

VOILIM, ut Me&i ex uno corporis latere m.~;or JciliitJs qu~anl cX altero<br />

no11 cdkhmh veniat. .Reiiikntiam QUORUM circccris p2rlbus<br />

denfitari proportionalem effe fuppono, U11dc 111 hl[cdiis qrJorulll<br />

vis refifkendi non efi ut denfitas, debet dcnfitas eo ufquc augeri vcl<br />

cdiminui, ut refifientk. vel tollatur ex~cKi~ vcl dcfefius filppleatur.<br />

Iwvenire & vim centripetmg & Me& reJJe&z~ yf!c~ ~O~~UJ<br />

in dcztca Spil’ali, dutu ruelocit&;r ~ege, revoh pote.~.<br />

Sit Spiralis illa T %I?. EX velocitnte qua corpus percurrit arcum<br />

quam minimum T g dabitur tempus, & ex altitudim T&<br />

qus efi ut vjs centripeta & quadrarum temporis, dnbicur vis. Delnde<br />

ex arearum, =qualibus temporum particulis confefiarum F’ ,J’,$<br />

& RSX, differentia RSr, dabitur corporis retardatio, & es retardatione<br />

invenietur refifientia ac denfitas hledii.<br />

,PROPOSITIO XVIII. PRO3LEMA V.<br />

ata Leg ~2s centripetd, invenire Medii de@tatem hz /o&Jhg&s,<br />

qua corps datam Spirdlem deJmiGet.<br />

ox vi centripeta invenienda eit velocitas in locis @@is, deinde<br />

ex velocitatis retardatione quazrenda h4edii denhas: ut in<br />

Propohione fuperiore.<br />

Methodum vero tra&andi haze Problemara aperui in huj+us Propoctione<br />

&&ma, & Lemmate &undo 5 6r Le&orem in hqulinpdi<br />

perplexis difquifieionibus diutius detinerc nolo. Addenda Jam<br />

funt aliqua de viribus corporum ad progredienduml dcque de@*<br />

rate & r&fientia Mediorum, in quibus motus ha&enus expofitl 86<br />

his affines peraguntur.


THEO~REMA XIV.<br />

Rhidi~ komogenei & irnmoti, quod in 5vaJe guocunque immoto C?UZ<strong>Up</strong>artes<br />

omnes ( fepoJta condtinomniurn<br />

centripetmtirn con/?de-<br />

CaJ I. In vak fplimies ABC claudatw & uniformiter conb<br />

primqtur fluidum undique: dice quod ejufdem pars nulla exdhs<br />

prefione movebitur. Nam fi pars aliqua D<br />

moveatur, neceffe efi, ut oinnes hujufmodi<br />

partes, ad eandem a centro diitantiati un- ’ YA.<br />

dique coniiitentes, fimil‘i motu fimul move;<br />

anCur; a.tque hoc adeo quia fimilis & a+<br />

qualis eit omnium prefio, & morus omnis,<br />

etxcluf~s,~pponit.ur, niG qui a preffione iL<br />

la oriatur. Atqui non poffimt omnes. ad<br />

centrum propius accedere, nifi Auidum adB<br />

centrum condenktur ; contra Hypothefin.<br />

%n. po&nt longius- ab eo recedere, nifi<br />

fluidum ad circumferentiam condenktur j<br />

etiam contra Hypothefin. Non poffunt firvata ilaa a centro difiantia<br />

moqeri in plagam quamcunque, quia pari ratione rnoveburb<br />

iw in plagam contrariam 5. In * plagas autem contrarias non potefi<br />

para


CWIA<br />

MAITHEMATI~A;.<br />

Lrs eadem, eodem temporc, moveri. Ergo fluidi pars w~lla de lo- L I I! E n<br />

,. Tuo movcbitur. & E. 53. s I:. c II h’ 1.l v F<br />

GUJ 2. Dice jam quad. tluidi hujus pnrtes omncs $Iwricx aquacr<br />

prctnuntur undigue : fit cnim E F pnrs $hrica Auidi, & ii.<br />

2~ undiquc non prcmirur xqualitcr , augcatur prcflio minor, uf--<br />

l:c dum ipfi undiquc premntur xqualitcrj & partcs cjus, per<br />

afilm primum, pcrmancbunt in locis his. Scd ante au&am prei:<br />

)mm pcrmanebunt in locis ibis, per Cafum culldum primum, &<br />

Lcjitionc prcflionis novx movebuntur dc locis his, per definitio-<br />

:1x Fluidi. Qux duo rcpugnanr. Ergo falro diccbnrur quad S~hr’J<br />

IT non undiquc prcmebatur xqualicer. $4 E, 9.<br />

c,$ 3, Dice prxtcrca quad divcrhrum pnrt~um Q~lwricarum x-<br />

ralis i;lt prcflio. Nnnz pnrtcs iphriccr: contigux ib muruo prcunt<br />

aqualitcr in punCto conra~us, per motes Lcgcm 111, Scd ‘&,<br />

:F Cafum i’ccundum, undiquc premuntur cadcm vi. Partcs igitur<br />

1~1: quxvis fphccricz non co~cigux, quia pars fphxrica intcrmcdia<br />

ngcrc potcfi utrnmquc, prcmcncur cndcm vi. & E. 59.<br />

c;CJ: 4. Dice jam quad fluicti pxtcs omncs ubiquc prcmuntur<br />

palitcr. Nam partcs dus quxvis tangi ~~OfIilnt n partibus Sphx-<br />

:.is in pun&is quibufcunquc, & ihi partcr ilhs Sphxric3s squalir<br />

prcmunt, per Cniilnl 3. Sr: viciilitn nb illis xqualitcr prcmulltur,<br />

:r Mows Lcgcm rcrcinm.


PIlOPCWTlO XX* THEOREM, XV.<br />

Sic D Hi11 fuperficies fundi, 8~ AE f<br />

:filperIicies fiiperior fluidi. Superficiebus<br />

i’phxricis illrlunleris B j?‘I(, CG L di[~inguatur<br />

fjuidum in O&es ConcenCricos x:-<br />

qualiter CraffOS j & concipe vim gravitaens<br />

agere folummodo in fiipMiciem fuperiorem<br />

Orbis cujufque, & zquales effe a-<br />

Qiones in zquales part-es ~uperficierum omnium.<br />

Premitmr ergo fuperficies fuprema<br />

J$E vi fimplici gravitatis proprix, qua &<br />

omr~es Orbis hpremi partes & luperficies<br />

*. .....*. .. .**<br />

Gxunda B FK (per Prop. XIX.) pro menfura fuua aqualiter premulltur.<br />

Premitur prasterea fuperficies kcunda BFK vi pro rie<br />

gravitatis, quz addita vi priori facit preaonem duplam. R ac<br />

prcilione, pro menfura fiua, & Super vi propriz gravitacis, id efi<br />

preflione cripla, urgetw fhperficies tertia CG L. Et fimiliter prep<br />

Gone quadrupla ursetur Ciperficies quarta, quintupla quinta, &<br />

fit deinceps. Prefllo igitur qua fiperficies unaquaque urgetur,<br />

nail efi ut quantitas iblida fluidi incumbentis, fed ut numerus Orbum<br />

ad ufque Chmitat&@ fluidi j & aquatur gravitati Orbis ‘in&<br />

mi mukiplkw per numerum Orbium: hoc eft, gravitati Iolidi cujus<br />

ukima ratio ad qylindrum przzfinitum, (G modo Qrbium &Igeatur<br />

qumerus 8~ minuacur craflitudo in infinitum; fit ut a&o<br />

gravitatls a filperfkk infha ad fupremam continua reddatur) fret<br />

mio z~ualitatis. &.db.t ergo fuperficies infima pondus cglin&i<br />

grzf-


Rl[Nc]rqA. MA n&g<br />

prafiniti. &E. D. Et fir& argument’atione patct Propofieio, LIBER<br />

ubi gravitas decrefcit in ratione quavis afignata difiantitr: a centro, SEC~~~‘V’*<br />

ut sh ubi Fluidum furfilm rarius efi, deorium denfius. .$&E,D.<br />

Curol. I. Igitur fundum non urgetur a totQ fluidi incumbentis<br />

pondere, kd earn folummodo ponderis parcem MEnet quaz ,in<br />

propofitione d e l cri b itur; pondere reliquo a fiuidi figura fornicata<br />

hitentato.<br />

Coral. 2. In zqualibus autem a centro difiantiiseadem f&per eE<br />

prefflonis quantltas, five fuperficies preiTA iit Horizoati parallela<br />

vel perpendicular& vel obliqua 5 five fluidmm, a ikpcrficie prcffa GKfurn<br />

continuAturn, firgat perpendiculariter recundLana.lil-rcam re&tm,<br />

vel firpit oblique per tortas cavitates & canales, eafque regulares<br />

vel maxirne irregulares, amplas vel angufiiflimas. Hi& circumfiantiis<br />

prefionem nil mutari colligitur, applicando demonfirationem<br />

Theoremaris hujus ad Cafius fingulos Fluidorun..<br />

Coral. 3. Eadem Demonfiratione coIligirur etiam (per Prop. XIX)<br />

quad Auidi gravis partes nullum, ex preflione ponderis kumbentis,<br />

acquirunt motum inter fe, fi modo excludatur motus qui ex<br />

condenlhcione oriatur.<br />

Cored. 4. Et propterea G aliud ejufdcm gravitatis f’ecificz corpus,<br />

quod fit condcnhtionis expers, fubmergatur in hoc ffuido, id<br />

c[=x prefione ponderis incumbentis nullum acquiret motum: non<br />

deficndet, non afcendet, non cogetur figuram fuam mutare. Si,<br />

fphzricum eit: manebit fpharicum, non obltante prefione; ii quadrarum<br />

cfi manebit quadraturn : idclue five molIe fir, five fluidi&<br />

mum j five fluid0 libere innatet, five fundo incumbat, Habet e-<br />

nim fluidi pars quazlibet interna rationem corporis fubmerfi, Sr par.<br />

efi ratio omnium ejufdem magnitudinis, figure & gravitatis fpecific3:<br />

fubmercorum corporum. Si c&pus fubmerfum fervaro pundere<br />

liquefceret & indueret formam fluidi; hoc, G prius afienderet<br />

vel delrcenderet vel ex preiiione figuram novam induerer, etiam<br />

~UI~C akenderet vel defcenderer vel figuram novam induere cogerecur<br />

: id adeo quia gravitas ejus catersque motuum cauk petmanent.<br />

Atqui, per Cai; $. Prop. x lx, jam quiekeret & figuram<br />

recineret. Ergo b% prius.<br />

Cwu2. T. Proillde corpus quad fpecifice gravius efi quam Fhidum<br />

fibi conriguum fubfidebit, Lk quod fpecifice levius eft aken:<br />

der, motumque & figurz mutationem confkquetur, quantum excefitis<br />

ilk vel defetius gravitatis eticere pofir. Namque exccfT’us<br />

$116: 97~1 &feLOcus racionem habet impulfus, quo corpus, alias in<br />

azg+li-


I,?, ~~~~~ aquilibrio cum fluidi partibus conltittitum, urgetur; k comparari<br />

C:O~L p 03 u ~1 pot& cum exccffu vel defe&u ponderis in lance akerutra ;librae.<br />

~WO,L 6. Corporum igitur in fluidis confiitutorum duplex& Gravitas<br />

: altera Vera & abfoluta, altera apparens> vulgaris 8z cornpa-’<br />

ra tiva, Gravitas abfoluta efi vis tota qua corpus deorfum tendit:<br />

yclativa 82 vulgaris eCt exceffus gravitatis quo corpus ,magis rendit<br />

deorfum quam Auidum ambiens. Prioris generis Gravitate par.tes<br />

fluidorum & corporum omnium gravitant in lock fuis : ideoque<br />

conjun&is ponder&us componunt pondus totius. Nam cotum<br />

on-me grave efi, ut in vafis liquorurn plenis experiri licet; & pondus<br />

totius aquale efi ponderibus omnium paruum, ideoque ex iifdem<br />

componirur. Alterius generis Gravitate corpora non gravirant<br />

in locis skis, id efi, inter fe coliata non pragravant3 ,fkd mutuos<br />

ad defcendendurn conatus impedientia permanent in Iocis<br />

5ik, perinde ac fi gravia non effent. QX in Aere funt & non<br />

przgravant, vulgus gravia non judicat. Qua: przgravant vulgus<br />

.gravia judicat, quatenus ab Peris pondere non fifiinentur. Pow<br />

dera vu1 i nihil aliud funt quam exceffus verorum ponderum fupra<br />

pon cf us Aeris. Un,de & vulgo dicuneur levia, quae tint: minus<br />

gravia, Aerique przgravanti cedendo fuperiora petunt. Comparative<br />

levia funt, non vere, quia defcendunt in vacua. Sic Q<br />

in Aqua, corpora, quz ob majorem vel minorem gravitatem defiendunt<br />

vel afcendunt, funt comparative & apparenter gravia vet<br />

levia, & eorum gravitas vcl lcvitas comparativa & apparens efi cxceffus<br />

vel deFe&kus quo vera eorum gravitas vel fiuperat gra’v;itatern<br />

aqua vel ab ea iilperatur. @y vero net prazgravando de-<br />

,fcendunt,, net prxgravanti cedendo afcendunt, etiamfi veris fuis<br />

ponderibus adaugeant pondus totius, comparative tamen & in fen..<br />

fu vulgi non gravitant in aqua, Nam fimilis efi horum Ca.fuum<br />

Demonfiratio.<br />

CoroX 7, C&z de gravitate demonfirantur, obtinent in aliis quibrifiunque<br />

viribus centripetis.<br />

Curol. 8, Proinde fi Medium, in quo corpus a.liqaod movetur9<br />

wgeatttr vel a gravitate propria, vel ab alia quacunque vi centripeta,<br />

& corpus ab eadem vi urgeatur fortius: tdifferentia virium<br />

XI% vis illa matrix, quam in pwcedentibus Propofitionibus use v,irn<br />

Gen tripetam confideravimus, Sin corpus a vi illa urgeatur levius,<br />

dif?‘erentia virium pro vi cenrrifuga haberi debet,<br />

Cord 3. Cum autem fluida premendo corpora inclufa ;non<br />

:muwlt eortum Figuras externas, paw infuper, per Co~ollarium<br />

Prop.


ap. x1x9 quod non mutabunt fiturn partium intcrnarum inter Lrnrrc<br />

I’k: proindeque, fi Animalia immergantur, & fknfatio omnis a mo- Seca”3”3<br />

tu partium oriatur j net kdent corpora immerfa, net ienktionem<br />

ullam excitabunt, nifi quarenus hzc corpora a compreflionc<br />

conden&ri poirunt. Et par efi ratio cujufcunque corporum Syitematis<br />

fluido comprimente circundati. SyItematis partes omnes<br />

iifdem agitabuntur motibus, ac G in vacua confiituerentur, ac folam<br />

retinerent gravitatem fuam corn arativatu, nifi quarenus fluidum<br />

vel motibus carum nonnihil re P lfiat, vel ad eafdem comprefione<br />

conglutinandas requiratur.<br />

PROPOSITI.0 XXI, THEOREMA XVI.<br />

Sit Fluidi cujuJdam den/b comprefmi proportiomaih, &Y pnrtco<br />

‘us a cvi centripeta dz$hntiis J&S a mm reciproce proportion&<br />

deorfkn trahantur : dice quad, /i d$!antiLo jIh jknaatw<br />

continue proportiona!es, denjttates Fbidi irt iifdem diJ?mtiis e-<br />

runt etiam continue proportionales.<br />

Defignet ATY fundum Sphazricum cui fluidum incumbit, S<br />

centrum, SA’, SB, SC, SD, SE, kc. difiantias continue proportionales.<br />

Erigantur perpendicula AH, B I’, C K, D L, E Al, &c,<br />

quz Gnt ut denfitates Medii in locis A, B, C, D, E; or: fpecificz<br />

AHBI CK<br />

gravitates in i&km Iocis erunt ut m3’ mJ;” C’J” kc. vel, quad<br />

AHBr-CK<br />

perinde efi, ut m =, m&c. Finge pri-<br />

xnurn has gravitates uniformiter continuari ab<br />

.A ad B, a B ad C, a C ad D, &c. fa&is per<br />

gradus decrementis in pun&is B,C, I), kc. Et<br />

hlz: gravitates d&E in altitudines ~423, BC,<br />

CD, kc. conkicient prefliones .4I5,Sl, CK,<br />

quibus fundum AI’Y (juxta Theorema xv.)<br />

urge tur. Sufiinet ergo particula A prefiones<br />

omnes A HP B I, GK, 2) L, pcrgendo in<br />

* infinitum, & particula I3 prefiones _ - omnes<br />

przter primam A flj 6% particula C omnes<br />

przter duas primas AI2, BI; & fit delnceps: adeoque part&<br />

euk primer: A de&as AN eft ad partlculte kcunda B den&<br />

Mm<br />

ratella<br />

R<br />

I


z:GcT PHl[@OSOPH1rlE NA RALIS<br />

DE kwTUtatem 231 ut fumma omnium AN-+Bil$CK-/-CDL in itifini-<br />

Convonu~ turn, ad iirmmam omnium B I + CK +D L, Szc, Et B1’ denfitas<br />

fecund= B, eR ad CK denfitatem tertia: C, ut fumtna ohnium<br />

B.Z+C.K+‘DL, kc. ad fummam omnium CK+TDL, &c.<br />

Sunt igitur Cummz ills diff’erentiis his AH, BI, Cd


I \


268 HIE NA RAEYS<br />

IJ~ Moru Centro S, Afymptotis SAP sx, ~efiribatur . Hyperbola qux,<br />

CfDIlPOllV~ vis, qux fccer perpendicula AH, B 1, C X, kc. m u,6,c, kc. uf ‘k<br />

pcrpendicula ad Afympcoton 8 X demiffa H t, Iti, l< w in 1”J, i, kp<br />

& &nGtatum<br />

diferentia t 14, @‘14/J Src. erunt ut Akl JA, n, Baz &c. Et,<br />

BJxui<br />

-J-~,&~.<br />

id efi, ut Ala, B b, &cl Eik enim, ex natura Hyperb&,,<br />

8 A ad AH vel St, ut t h ad A a, adeoque AHxrl? 3 d xquale A~,.<br />

BJTXZli’<br />

Et fimili argument0 ef? -J-B- aspale Bbj kc.. Sunt-aut em Jh<br />

B d, Cc, &c. continue proportionales, & propferea differentiis k-<br />

is Aa - 6’& Bb - Cc, kc. proportionales; ideoque ditierentiis<br />

hike proportion&a funt refiangula tp, zc~,&c. ut & iummis differcntiarum<br />

Aa - Cc vel Aa - 1) Q fiimmxz reLtangulorum tp + 214.<br />

vel tp + 1 4 + w t. Sunto ejufinodi. tecmini quam plurimi, SC Turnma<br />

omniumg difkrentiar~m, puta Ad - Ff, crit fitmmlr: omnium<br />

rc&angulorum ) puta 2 t b n, proportion&s. nugeatur qumerus.<br />

terminorum Sr minuantur difiantix punQorum A, B, C, &c, in inniturn,<br />

& reQangula illa avadent zequalia arex Hyperbolica: xtbbn,<br />

adeoque huic areas proportionalis efi differentia Aa - r;$. Swman-<br />

.4W


‘1)wNCIPIA MATHEMATIcA.' lx691 *<br />

~.;ii, Jim dikmtk qulrlibet, puta SA, SD, SE in progrrOioceMu- tysea<br />

&I; & d~fferentiz Aa -Dk!, Dd-Fferunt 3zquales; & propter- S2cc~‘D1~r<br />

ea dliTcrentiis hike proportionales arex tblx, xlnz xquales erunc<br />

inrer 12, & denfirares St, Sx, Sx, id efi, Ali, BI;,. FAT, contl-,<br />

nue propf.;rrlonales. &T&E. 53.<br />

CO&. H~nc G dentur Fluidi denf.itates dua quxvis, pwtaiAH<br />

& C,K, dabxur area t h k w harum diFferen& tnw refpondens; &<br />

inde invenictur deniitas PN in alritudme quxunque W, fimendo<br />

arearn t h nx ad aream illam datam Z h k w ut efi, differenti<br />

Aa - fif ad dift‘erentiani Apz - Cc,<br />

Simili argumentatione probari potefi; quod ii gravitas particu-,<br />

larum Fluid’i diminuatur in triplicata ratione diltanriarum a centroq<br />

& quadrarorum diltantiarum SA, SB, SC, kc. reciproca . (nem- .<br />

,f Acxb. S,Acub. S’A cub.<br />

pe -SA4, --7---- 3. umantur in progrefione Arithme*<br />

J.Bq acy If<br />

tica j de&tares k H, B .I,7,CI


2qo py”J:f~~~s:,oPEIIx SIP, u +<br />

tione diftantia. Fingatur quad V~S comprimens fit ifi duplicara ~<br />

~Q~I~~R~hI rat-one denfitatis, & gravitas reciqroce ,in ratio?e duplicata d&m.,<br />

tiz, & denfitas erit reciproce ut d$antla. Gaius omnes percurrere<br />

longum eat*<br />

‘pgmxXTI0 XXIII. THEOREMA xw1[1,<br />

si F&di eg p&ds<br />

se mutu~ fu$entibus<br />

CO~PO& den&a+<br />

fdtcompre~o, vires centrifugs p~rtic~l~r~m Jtant reciproce proportion&s<br />

dijantiis centrorw J~or~m- Et vice rue~Ju, pdra-<br />

ticuld air&us gua Junt reciproce proportiowales dzpantiis cm.<br />

,troruwz J~~~LuB Je ~,Gttio fugientes componunt l?hidm HdJ3a’-<br />

cum, cv’us der$ta eB compre@oni proportiomlis.<br />

]nclu& intelligatur Fluidum in fpatio cubic0 ACE, d$n corn..<br />

yrefiorle redigi in fpatium cubicum minus n Ce j & partIcularurn,<br />

.fimilem fitum inter ce in utroque<br />

Cpatio obcinentium, difian-<br />

.tk erunt ut cuborum latera<br />

AL?, ab; & Medii.denGtates<br />

reciproce ut fjjatia continentia ... . . . ..... .<br />

A Bczh. 6-z db cub. In latere<br />

cubi mnjoris ABCD capiatur<br />

quadratum 2, ‘P aquale Iateri<br />

cubi minoris db; & ex Hypo-<br />

Aeli, prefflo qua quadrarum 93 T urger Fluidum inclufilm, erit ad<br />

,pretI’ionem qua latus illud quadratum db urget Fluidum inclufum<br />

ut Medii denfitates ad invicem, hoc efi, ut a6 CL&. ad ABcub. Sed<br />

preflio qua quadratum 40 B m-get Fluidum inclufum, efi ad prefionem<br />

qua qundratum 53 T urget idem Fluidum, ut quadratum I> B<br />

.ad quadrarum 59 T, hoc efi, ut AB qwd, ad n b qtiud. Ergo, ex<br />

;Rquo, prefio qua latus “D B urget Fluidum, eiZ ad preflionem qua<br />

latus db urgct Fluidurn, ut ab ad AB. Planis FGIY, fgh, per<br />

tmedia c.uborum duQis, difiinguatur Fluidurn in duas partes, & hz<br />

fe muruo prement iifdem viribus, quibus premuntur a plank AC, a~,<br />

hoc efi, in proportione ab ad AB: adeoque vires centk,ifugx, quibus<br />

hz prefiones fufiinentuf, func in eadem ratione, Ob eundem<br />

.particularum numerum fimilemque fiturn in utroquc cube, vires<br />

+q,uas particallz omnes kcundum ,plana ,&‘G H, fg k e.xercent in om-


PAGE 272 MISSING


274 PHILBSBPHI& N.A.<br />

DE nr o T 0 tur eadem per datam arcus Cycloidis parcem CO, Sr fumatur ar-<br />

CORI~ORUX cus 0 d in racione ad arcum C‘D quam habet arcus 0~3 ad arcum<br />

CB : 6: vis qua COYPUS indurgetur in kfedio refifiente, cum fit ex+cefi~<br />

V~S cd fupra refifientiam CO9 exponetur per arcum Od, adeoque<br />

erit ad vim qua corpus 2) urgecur in Mcdio non refifiente,<br />

in loco ‘22, UC arcus 0 Q ad arcum CD ; & propuxxtta etiam in loco<br />

B ut arcus 0 B ad nrcum CB. Proinde fi corpora duo, ‘?I, Q<br />

exeant de loco ~3, & his vjribus urgeancur: cum vires. Cub initio<br />

iillt ut arcus CB 6: OB, erunt velocicates primz & arcus prima<br />

defcripti in eadem ratione. Sunro arcus illi B “23& Bd, & arcus<br />

reliqni CbD, On mm in eadem ratione. Froinde vires, ipfis<br />

CD, Od proportionales,tlyancbunt in eadem racione ac 1ib inicio,<br />

6~ propcerea corpora pergent arcus in eadem racione<br />

bcrc. Igitur vircs &<br />

fimul defcri-<br />

,veIocita tcs EC arcus rchqui<br />

C*D, Od remper<br />

cruntutarcustoti LB,<br />

OB, & propcerea arcus<br />

illi reliqui iimul z<br />

dekribentur. Qare<br />

corpora duo FD, d iimu1<br />

pervenient ad loca<br />

C 2-c 0, alterurn quidem<br />

in Mcdio non refiifente<br />

ad locum C, &<br />

a]terum in M&i0 refi fiiente ad locum 0. CU~I autem vdocitates ifi<br />

c & 0 fillt ut arcus CB, OBj erunt arcus quos corpora ukerius<br />

pergendo fimul defcribunt, in eadem ratione. Sunto illi CF &<br />

0 6. Vis qua corpus D in Medio non refik.nte retardatur In E<br />

efi ut CE, & vis qua corpus n in Medio refiReate retardatur in B:<br />

en UC funyma vis ce g refifientiz CO, id eft ut Oej ideoque viyes,<br />

quibrrs corpora retardantur, fimt ut arcubus (CI’E, 0~ proportionales<br />

arcus CB, OBj proindeque velocitates, in data illa ratio-<br />

31e retardatx, manent in eadem illa data racione. VeIocitates igitur<br />

& arcus iifdem defcripci femper func ad invicem in data illa ratione<br />

arcL1um CB & OB; & propterea ii cimantur arcus toti A&<br />

aB in eadem ratione, corpora ‘22, d fimul defcribent hos arcus:, 8~.<br />

in locis A & a rnotum omnem fimul amittent. liCochro.na~ runt:<br />

igitur ofiillationes tot%, & arcubus totis BA, BCJ proportionales:<br />

funt arcuum partcs quslibet. 1322, I3 ca’ ~1 B 23, B 6 CLUE fhd de,--<br />

4:ribL~ncur. ,g+. 5%<br />

_<br />

coraE”L


~tirporum F~~epe~dulor~~~, gtiibus reJ$+lp<br />

aJci&m&ze~ in ~+doide fint IJachyond.<br />

in rdtiogt vefaci”Edttfan,<br />

Nam ii corpora duo, a centris fufpenfionum zqualiter diltantia,<br />

sjfcillando dekribant arcus inxquales, & velocitates in arcuum parhbus<br />

correfjpondentibus finr ad invicem ut arcus tori: refifientix<br />

. velocitatibus proportionales, erunt etkm ad invicem ut iidem ar-<br />

&w. Proiode ii viribus morricibus a gravitate oriundis, quaz fins.<br />

UC iidem arcus auferanrur vel add;mtur 113 refitkntix, erunt dif-<br />

Wenti% se1 furnrnz ad invicem in eadem arcul1r-n ratione: cumque<br />

yelociraruti inci’ementa vel decrement,1 fint ut hre diO?erentiz veE<br />

+rnrnx, velocitates fkmper erunt ut arcus toti: Igitur velocitates,<br />

fi fint in aliqUo cafil ut arcus toti , manebunt kmper in eadem ra-<br />

Cone. Sed in principio motus 3 ubi corpora incipiunt defiendere<br />

& arcus illos dGzribere, vires, cum fint arcubus proportionales, gcneiabunt<br />

x&~citAtes arcubus proportionales. Ergo velocitates fern-<br />

per erunt ut arcus roti defcribendi, & propterea arcus iili fin4 dc-<br />

Ircriknttir. &$ E. f;D.<br />

si Corporibus hmependtilti reJ$Gur in duphnta yatiane welocit&m,<br />

d$fkntiSe ititer tempom o/&Z&anzmz in Me&o rel;-<br />

Jfente uc tampora oJ&Ja~ionbtm in tj’uJhm gru~22atis je+ice<br />

M&d& tioti rej$fente, erunt urcubus oJci.ZZando deJcriptix proo~&za~&,<br />

quitm proxJme.<br />

Nax-h p‘e?dulis- &qualibus in Medio refiftentc deiiribarrttir arcus<br />

inzquales A, B; & refifientia corporis in arcu A, erit ad refiitentiam<br />

corparis in parte correfpondente arcus B, in duplicata ratloarxe<br />

yelocitatumJ id eR, ut A A ad B B1 quam prohx. Si xii-<br />

Nn 3 fientia


II E ?.I0 T c aclltia iI1 arcu B eiret ad refiifenriam in arcu A ut A B ad A A ;<br />

C‘OK~OI:V:~: cempora in arcubus A & I3 forent zqualia, per h3pofitionem fupcriorcm.<br />

Idcoque refifientia A A in arcu A, vd A k% in arcw B,<br />

ce;cir excei~ilm temporis in arcu A hpra tempus in Media non’<br />

rci;Rclltc; & refi[tentia B B efficit exceffum ternpork in ~LXI B<br />

iilpra ternpus in hlcdio non refifcente. Sunt autem exccffis illi<br />

IIC ITires eficienres A B & J3 B quam proxime, id efi, UC arcus<br />

P A &Y B. 2. ‘E’. D.<br />

c’~T~L, I. Hint cx oWationum temporibus, in Media refifiente,<br />

ill arcubus insqualibus fakhrum, cognoki poirurlt tempora OfcilIa..<br />

tionum in cjufdem gravicatis fpecificz Media non refifientc. Nam<br />

dii-i‘ercntia temporum erit ad cxceirum temporis in arcu rninore fupra<br />

tcmpus in hkdio non refiiflente, ut difFeren& arcuum ad apcum<br />

minor-em.<br />

C’artil. 2. Ofcillacioncs breviores funt magis Ifochron~, & bre-<br />

-r:ii?imzz iii&m tcmporibus peraguntur ac in Media non refifiente,<br />

quam proxime, Earum vero quz in majoribus arcubus fhnt, tern-- .<br />

r:~ hit paulo majora, proprerea quod refifkatia in defcenfu carporis<br />

qua tempus producicur ) major fit pro ratione longitudinis<br />

in dekenfu defcripts, quam refifkntia in afcenfil hbfequente qua<br />

tcmpus contrahitur. Sed & cempus ofcillationum tam brevium<br />

~UXI~ longarum nonnihil produci videcur per motum Me&. Nam<br />

corporibus tardefcentibus paulo minus refifiitur, pro ratione velo..<br />

citntis, & corporibus acceleratis paulo magis quam iis qua uniformiter<br />

progrediuntur : id adeo quia hkdium, eo quem a corparibus<br />

accepic mow, in eandem p&am pergendo, in priore cafu lnagis<br />

agitatur, in poiteriore minus j ac proinde magis vel minus cum<br />

corporibus motis confjpirar. Pendulis igitur in d&enfu rmgis re.-<br />

fiitit, in afkenfu minus quam pro ratione velocitatis, & ex’utraque<br />

criufi tempus producitur.<br />

momentorum iemporis, erit ~‘us reSsl/2entbt ad vim graruitath<br />

ut excefihs wcus deJcenJu toto de&@ jipru SCUM u$iienfti<br />

&bJe&nte deJcripturn, ad penduli hwgitudinem duplicattim.<br />

Defigllet BC arcum defcenfii dekriptum, Cla arcum akenfu deh-iptun.1,<br />

6ss Aa di~crentiam arcuum : LQZ fiaratibus qua in Propa<br />

ditionrz


CIPI A MAT1E-IE ATICA. ,277’<br />

firto~l(3 xxv cotlfiru&a 8~ denmnltrata, GJntt erit vis qua corpus Ernei-t<br />

oictllarls urgotur in 10~0 quovis !ZI, ad vim rcliCtenti32 ut arcusS~CuT~z”US~<br />

CD ad arcurn CO, qui jrcmifis cfi difkrentin: illius Aa. Ideoque<br />

vis qila corpus olcillans urgeCUr in Cycloidls principio fi:u pun:to<br />

altilho, jd CR, vis gravitacis , wit ad rcfiIEontiam ut ucus Cycioidis<br />

inter pun&m illud fi~pr~n~utn & punBum infimum C ad<br />

arcum CO j id cfi (ii arcus dupliccntur) UC Cycloidis totius x-cusL,<br />

GX d~pla penduli longitude, ad mum Aa. G@CE. ‘D.<br />

ROPOSITIO XXIX. PROBLEh4A vr,<br />

Sit n a ( Fig, Prop. xxv) xcus oEdlatione int:gra dcfcriptus,<br />

litque G infimum Cycloidis pullRulTI, r! CZ fcmih arcus Cycloidis<br />

totius, longitudini Pcnduli IP.J~IS 5 & qwritur rciihmtia cob


Dr. J,~~V w aream % ET UC 0 $J,ad 0 C. Dein perpendiculo MN a~~~~da~~~<br />

CQRPQRUM ,$rca Hypcrbolica'YIl~~~qua~t ad areamHyperbolicam 5?.lE&<br />

ut arcus CT.2 ad arcum B C defceniu dckriptum. Et fi petpendicw<br />

lo H G abfcindacur area Wpperbolica !PIG& quz fit zid areah<br />

“P I,?2 $ tit arcus quilibet CD ad arcum B C defcenfcl toto d&<br />

tiriptum : eris reiitlentia in loco ‘;5) ad vim gravitatrs) ut aretr<br />

‘AIEF-IGHad<br />

aream TIENM.<br />

0%<br />

Nam cum vires a gravitate oriundz qui bus corpus in lock Z,B,YI,<br />

/r: urgetur, ht ut arcws CZ, CB, CD, Cn, t4k arcus illi fint tit area:<br />

b5!‘iNM,cTIE,C&TPGGX, TPPrCj exponanrurtumarcustumvires<br />

per has areas refpeflive. Sir infupcr l>d fpatium quam minimum<br />

a &3rp6re ckk~ndente dekripttim, & expontitur idem per areain<br />

quam minimam R Ggr parallelis R G, rg comprehenfam; & pro-<br />

ducatur rg ad b, ut ht G Hbg, &.RGgr conremporbnea arearum<br />

OR<br />

1 G 23, T I G R decrementa, Et area - oRIE F-IG H incremen-<br />

rum GHbg- &!- lEF, feu RrxHG- - Rr IE F, erit ad are;t<br />

02<br />

OX<br />

%‘rd”R decrementum &Ggr feu RrxRG, ut HG--<br />

1E.P<br />

0%<br />

OR<br />

ad RG; adeoque ut ORxHG-- IEF ad 0 Rx.GR feu<br />

02<br />

~OTX,T~,~~~~~(~~~~~~~~~~QRXHG,~RXHR-O~~GR~<br />

iHi!HK--QTPI’C, TIHR & T.ZGR+IGH) UC TIGR+<br />

OR<br />

2.E.F ad 0 P IK, Jgitur di area -b<br />

IkG?- OYR 0%<br />

oRIEF-lGH<br />

dicatur<br />

J


dicatur Y, atque area? PIG R decrementurn R Ggr de&w, erit LlnEll<br />

increnle:ltunl arelt: Y UC I)IGR --Y. SECUNDUZ.<br />

Quad ii V defignct vim a gravitate oriundam, arcui defcribendo<br />

CD proportionalem, qua corpus urgetur in I> : & R pro refiltentia<br />

ponatur: erit V -R vis tota qua corpus urq33.w in 13. Efi<br />

itaque incrementum velocitatis UC V - R St part&h illa temporis<br />

in qua fa&um et? conjun&im : Sed & velocitas ipfa efi ut incrementurn<br />

contemporaneum ibatii defcripti dire&e & particula eadem<br />

temporis inverfe. Unde, cum refifientia ( per Hypothefinj<br />

fit ut quadraturn velocitacis, incrementurn rcfiitentiaz (per kern. 11)<br />

erit ut velocitas &c incrementurn velocitatis conjunfiim, id efi, ut<br />

momenrum Epatii 8~ V - R conjuntiim; xrque adeo, fi momcntuul<br />

fpaeii detur, ut V --IL 5 id efi, ii pro vi V icribattar ejus exponens<br />

I) IG R, & refiilentia R exponatur per aliam aliquam arcam<br />

!Z, ut FlGR-ZZ.<br />

Igitur area 5” I GA per datorum momentorum fitbduhnem<br />

uniformiter decretiente, crefcunt arca Y in ratione ‘P 1GR - y,<br />

& area ‘Z in ratione ‘f IG A -25. Et propterea G arell: Y SC Z G-<br />

muI incipiant SE fi-lb ~niti~ SXJWI~S dint, hz per additionem zqualium<br />

momentorum pergent effe zquales, St zcqualibus itidem momentis<br />

fubinde decrefcenres fimul evanefcent. Et viciflim, ii fimul<br />

incipiunt 86 fimul cvanefcunt , zqualia habebunt momenta & fernper<br />

erunt zquales: id adeo quia ii refificntia 2 augeatur, veloci-<br />

ras una cum arcu iHo Cd, qui in afcenfu corporis dekribitur,dimi.<br />

iwetur ; & pun&O in quo.motus omnis una cum refifientia cecat<br />

propius accedente ad punhm C, refiitentia citius wane&t quam<br />

area Y. Et contrarium eveniet ubi refifientia dirninuitur.<br />

Jam vero area 2 incipit definitque ubi refifientia nulla efi, hoc<br />

elt, in principio & fine mow, ubi areus C 59, C7.l arcubus C B &<br />

Ca aquantur, adeoque ubi recCta R 4; incidit in reQas R.E & CT.<br />

/-I n<br />

Et area Y feu “$<br />

eoque<br />

IE F--1G Aif incipit dehitque<br />

ubi nulla efi, ad-<br />

ubi @ mI Iif ;G F SC IGH xqualia fimt : hoC efi (per con-<br />

firufiionem) ub? re&a R G incl’ciit in reLOsas gE & G T, Proindequc<br />

arez ihe dim@l inciphma; c 7,: fimul evanekunt, & propeerea<br />

femper ilunt xquales. Tgitur area 2F oRPEF-PGM xqualis efi<br />

* cd<br />

arez 25, per quam rdifier;ria exposCwr, 8s propterea eit ad aream<br />

“PI NM per quam gcavitas expoe’liwrj ut refifientia ad gravitytern.<br />

g& E,CDP<br />

&-or64


De %lOTU<br />

c on I’ 0 II L’ hl (‘&o,( 1. Efi igitur refiffenria in 10~0 infko ad vim gravitath<br />

ut area gFz IE F ad aream T INM<br />

C’~~~L 2. Fit autem maxima, ubi area P 1E-I W efi ad arearn<br />

IE$’ UC 0 R ad O.& Eo enim in cab monxntuM ejus (nimiru~<br />

‘p IG X -Y) evadlt nullum.<br />

coral. 3. Hillc etiam hnotefcit velocitas in loch fingulis : quippe<br />

qu’~: efi in ihbduplicata ratione rcfikxxiaz, & ipfo motus inirro a+<br />

guatur velocitati corporis in eadem ,Cycloide abfque omni reGBenc<br />

r,~a okillantis.<br />

Caterum ob dificilem calculum quo refifientia & velocitas per<br />

hanc Propofitionem inveniendz cum, vifum efi Propofitionem fe4<br />

quenccm hbjungerc, qu;1: & generalior fit St ad ufus Philofo,phiy<br />

cos abunde ratis accurata.<br />

Exponatur enim rum Cycloidis arcw9 ofcillatione integra de-<br />

Jcriptus, per reQam iilam iibi squalem a L3, turn arcus yui defcriberetur<br />

in vacua per longitudmem AB. Bifecetur AB in C, & pun-<br />

&urn C reprrrfentabic infimum Cycloidis pun&urn, Sr erit CD ut:<br />

ais a gravitate oriunda, qua corpus in D fecundurn tangentem<br />

Gycloidis urgeturr eamque habebic racionem ad longitudinem Pcnduli<br />

quam habet vis in I> ad vim gravitatis. Exponarur igitur vis<br />

41Ia per longitudinem CB, S; vis gravitatis per longicudinem pen-<br />

&Ii a SE fi in .D E capiatur I) K in ea ratione, ad longitudirlem<br />

penduli


P R 1 N c $ p IB: A 54. 8 I<br />

Is I 1: t! It<br />

pnduli quam habet rcfifientia ad gravitatem, erit ‘23.K exponevs<br />

rejifientis. Centrs C & intervallo CA vel CB conltruarur &3X1- ““” I””<br />

circulns B Ee A. DeCxibat autem corpus tcmpore quam minirn0<br />

ipatium 23 d, Sr ereL’tis perpendiculis 2, E, de circumi’crCnt$ w-<br />

currenribus in E 6r e, erunt haec ut velocitates qua” corpus 111 va.-<br />

CLIO, dekendendo a punL& ,B, acquireret in locis’ 23 & Cl. Patct<br />

hoc per Prop. LII. Lib. I. Exponatm.tr itaque 11512 velocitates<br />

lperpendicula illa DE, de; fitque D F velocitas quam acquirzt<br />

in D cadendo de B in Me&o refifiente. Et fi cenrro C & incerwallo<br />

CF defcribarur Circulars .Ff &I occurrens re&is de 8~ A B II-I<br />

f & i’& erit ,&! locus ad quem deinceps abfque uiteriore refifiengia<br />

afcenderet, & df velocitas quam acquireret in d. Wnde etiam<br />

fi Fg defignec velocitatis momentum quad corpus D, dekribendo<br />

i$atium quam minimum I) a’, ex refifientia Medii amictit ; 8r fuz-natur<br />

CN zqualis Cg : eric N locus ad quem corpus deinceps<br />

zabcque ulteriore refiitentia afcenderet, & MN erit decremencum<br />

zzfcenfus ex velocitatis illius amGone oriundum. Ad a'f demitta-<br />

EUT perpendiculum Fm, tk velocitatis 2) F decrementurn Fg a<br />

Hefifientia “23 K genitum, erit ad velocitatis ejufdem incremencum<br />

592 a vi CD genicum , ut vis generans D K ad vim generancem<br />

c 13. Sed & ob fimilia<br />

criangula Fm f, Fbg,<br />

F’k, C, eit ,f aa ad k;m<br />

6ku I)d, ut CD ad<br />

5D F; & ex zquo Fg ad<br />

5Dd ut DK ad DF.<br />

tern Fh ad Fg ut DF<br />

d CFj St ex aqua<br />

gerturbate,Fb ku MN<br />

Z)d ut ‘DK ad CF<br />

u CM; ideoque filmma omnium MN x Ck’aqualis erit fummaz<br />

lomnium I) d x I) IC. Ad pun&urn mobile M erigi kmper intell&<br />

gacur ordinata reQangula zqualis indeterminaca: CM, quaz motu<br />

continua ducacur in totam longitudinern Aa; & trapezium ex ills<br />

motu dekriptum five huic zquale reQangulumA1z x 4 a B zquabitur<br />

fimmaz omnium MNx C.iV, adeoque fknma ommurn ZJ dxa;l.~~<br />

id efi, arex BKkVTcz. &E. 2>.<br />

COroL Hint ex lege refifientia: & arcuum Cd, CB difkrentia Aa,<br />

-Golligi potefi proportio refifientk ad gravitatem q,uam proxime.<br />

. Nam<br />

per


zsz PHILOS0PHI.E l’hi7i<br />

D E hf ti T V Nam fi uniformis fit refifientia 9 K, Figura dB .Kk T re&angw<br />

cosroR”” lum crit filb &a & DK; & inde re@angulum fiub iBa & Aa<br />

crit squale r&angulo 1Tub Bn & 2> I in Medio non refifiente, &iUatione<br />

inregra dcfcriberet longitudinem B A, velocitas in IOCO quovis-.D<br />

foret ut Circuli diametro AB defiripti ordinatim applicata 2) E.<br />

Proinde cum Bn in Medio refifiente, 8r B A in Medio non refiitente,<br />

zqualibus circiter temporibus defiribantur ; adeoque velacitates<br />

in fingulis ipfius<br />

Ba pun&is, fint quam<br />

proxime ad velocitates<br />

in pun&is correfponelentibus<br />

Iongitudinis<br />

BA,uteRBa ad BA;<br />

erit velocitas 53 I-- in<br />

Medio refiltente ut Circuli<br />

vel Ellipkos fupcr<br />

diametro B n dekripti<br />

ordinatim appkata j adeoque Figura B MVT’LZ Ellipfis, quam proxime.<br />

Cum refifientia velocitati proportionalis fupponatur, fit OY<br />

exponens refifkentik, in pun&to Medio 0; & Ellipfis u B A 7/“$,.<br />

centro 0, femiaxibus OB, 0 Y defiripta) Figuram aBKVT,<br />

eique zquaIe reQanguIum Aa xBO, zequabit quamproxime. Efi<br />

@iturAaxBO ad OYxBO ut area Ellipkos hujlns ad OVXBQ:<br />

Id efi, An ad 0 Y ut area femicirculi ad quadratum radii, fine: ut<br />

IX ad 7 circiter: Et propterea I’1 Au ad longitudinem penduli ut’<br />

corporis ofcillantis refiitentia in 0 ad ejufdem gravitatem.<br />

Qod fi refifkentia 13K fit in duplicata ratione velocitatis , Figura<br />

B KVTa Parabola erit verticem habens Y & axem 0 Y, id..<br />

eoque aqualis Grit reQangulo filb ; Bla & 0 T quam proxime, Efi<br />

igirur reQangulum fu b i B a ik Aa zquale re&angulo fub ~BA<br />

& 0 Y, adeoque 0 Vazqualis $Aa: & propterea corporis ofcillatitis<br />

refifientia in 0 ad ipfius gravitatem ut t&a ad longitudinem<br />

Penduli,<br />

Atque has concluliones in rebus pratiicis abunde fitis accurata$.<br />

eire cellfeeo~ Nam cum Ellipfis vel Parabola B R Y$a congruat,<br />

cum


PRIN@IPEA kfATHEr\/lATICAl 29;’<br />

cum Figura B KPT LZ in punLto medio P” hsc ii ad partem al- !.!?: ‘:<br />

terutram B R Vvel VSa excedic Figuram illam, deficiel: a13 cadem 3:~ I- :,;‘YL<br />

ad partem alteram, & fit eidem xqwbitur quam prsximc.<br />

PFVX?OSITXQ XXXI. THEOREMA XXV.<br />

Britur enim difFerentia illa ex rerardatione Pendufi per relifientiam<br />

Medii, adeoque et% ut retardatio tota eiquc proporrionalis<br />

refifientia rerardans. In fuperiore Propofitione re&angulum<br />

iirb re&a $ aB & arcuum illorum CB, Ca diEerentia An, -<br />

zqualis erat arez B KT: Et area illa, ii maneat longitudo n B,<br />

augetur vel diminuitur in ratione ordinatim applicatarum “D I


Ex his, Propofirionibus, per ofcilla~io~Ies Fe~duhrum in Me&is<br />

q~~ib~~f,-unque, invenire lices refii’tenblam kfd.QrLmL Aeris vero<br />

refiftentianl invefiigavi per Experimenta kquentia. Globwm ljg.’<br />

neum pondere unciarum Romanarum 57?3, diametro digitorum<br />

Lo~&w$wn 6: fabricatum ) if10 tenui ab unto his firmo fufpeIrdi,<br />

ita ut inter urIcurn AT centrum of’cillationis Globi difiansia eret<br />

gedum 10;. II-I file pun&urn notavi pedibus decem &r uncia llrla<br />

a centro hfpenfionis dihns ; & e regione pun&i i&us COlloCavi<br />

Regulam in digitos difiin&am 3 quorum ape notarem longitudi,<br />

nes arcuum a Pendulo dekriptas. Deinde numera-vi okillationes<br />

q&us Globus o&avam mows fi.li parrem amitteret. Si pendu-<br />

]um deducebatur a perpendiculo ad difiantiam duorum digitorum,<br />

.Q inde demittebatur; ita US toto Cue defcenh defcriberet arcum<br />

duorum digitorum, toraque okillatione prima, ex defienfu St afcenfu<br />

fubfequente compofita, arcum digitorum ferc quatuor : idem<br />

ofcillationibus 164 amilit oQavam mows hi partem fit ut ultimo<br />

Cue afcenfu defcriberet arcum digiti unius cum tribus partibus<br />

quartis digiti. Si primo dekenfu defcripfit arcum digitorum quatuor<br />

; amifit ofiavam mow partem okillationibus 1.2 I, ita ut akenb<br />

fi, ultimo defcriberet arcum digicorum 3:. Si primo dekenfu de&<br />

tiripfit arcum digitorum o&o9 kxdecim, triginta duorum vel fenaginta<br />

quatuor ; amifit o&avam motus partem ofcillationibus 6y,3 r$,<br />

P 8$, 95, re~pe&tivc: Igitur differentia inter arcws dekenfi prima<br />

8~ afcenfu ultimo dekriptos, erat in cafu prima, &undo, tertio,<br />

qnarto, quinto, fexto, digitorum i9 “;> I, 2, 4, 8 refpc&ive. Dividantur<br />

ea: different& per numerum ofcillationum in cafi unoquoque,<br />

& in ofcillatione u,na mediocr& qua arcus digitarum 3$, 7$,<br />

15, 30, 60, 120 dekripcus fuits differentia arcuum defcenh & fubb<br />

fequcntc &en& detiriptorum, erit -& $-, 6, 5, -$ 2 partes di-<br />

giti recpe&ive, Ha: au.tem in. majoribus okillationibus iiint in duplicata<br />

ratione arcuum dekriptorum qham proxime, in minoribus<br />

vero paulo majores quam in ea ratio,ne; & prapterea (per Coral. 2.<br />

Prop. XXXI Libri hujus) refiftentia Globi, ubi celerius movetur,<br />

elZ in duplicata ratinne velocitatis quam proxime 5 ubi t,ardius, pau-<br />

I0 major quam in ea ratione. /


Qefignet jam V velocitacem maximum in okillatione qmvis, ~~~~~<br />

fintque A, B, G quancitates da&, & fingamus quad diiFerentia SECU~I)IJL<br />

arcuum fit A V + B V”i -/- C VL. @urn veIocitatcs maximz Ii17t in<br />

Gycloide ut kmifis arcuum ofcilIand0 dekripcortmi , in Girculo<br />

vero ut i‘emifinlum arcuum illorum chordzj acfco~~ue par&us<br />

arcubus majores fint in Cycloide quam in Circulo, in ratione<br />

12mifium arcuum ad eorundem chordas; tempera autem in Circulo<br />

fint majora quam in Cycloide in velocitatis ratione reciproa<br />

j pacet arcuum diR”erentias (qw funt ut r&O-en& & quadratum<br />

tempo+ conjunQim) eatiem fore, quamproxime, in utraque<br />

Ckarva: deberent enim dif%renriz ilk in Cycloide augeri, una<br />

cum refiiIent& in duplicata circiter rarione arcus ad chordam, ob<br />

velocitatem in ratione iild fimplici au&am ; & diminui, una cum<br />

quadrato temporis, in eadem dupiicata ratione. ftaque ut redu3io<br />

fiat ad Cycloidem ) ezdem fimendz fint arcuum diferentk quz<br />

fuerunt in cSircuI0 obfervats 9 veloci ta tes vero maxima ponendze<br />

Cunt arcubus dimidiatis vel integris, hoc eff, numeris f, I, zz><br />

4, 8, x6 analogs Scribamus ergo 111 cak fecundo, quart0 & kx-<br />

Co numeros 1, L$ & I6 pro V j & prodibit arcuum diflkrentia<br />

-5<br />

3<br />

b = A + B + C in cafu recundo; --$=.+A+8B-+ldC in cafe.<br />

121<br />

2<br />

quart0 j & -$ - rGA + 64 EL)- 2 56C in cafii ftixro.<br />

Et ex his ire:-<br />

quationibus,, per debitam collationem & redu&ionem Analyticama _<br />

fit A =o,oooo916, B = 0,0010847, & C= o,ooz9558: Elt ip;itur<br />

difTer&tia arcuum Ut O,Qm3o916 ~~0,0~~~8~~~~~0,~~~9~.~8~":<br />

& propterea cum c per- Corollarium Propofitionis xxx ) sefifientia<br />

Globi in media arcus ofcillando defcripti, ubi velocitas efi V,<br />

fit ad ipfius pondus UT 1'1 A V -+ $$ B V$ -+t C V* ad longitudiwm<br />

Benduli; fi pro A, B & C fcribantur numeri inventi fiet refifientia<br />

Globi ad ejus pondus, ut OPOO s 83 V + 0,0007546 Vi + 0~0022169 V3 ’<br />

ad longitudinem Penduli inter centrum fufpenfionis 8.~ Regulams<br />

id e.f%, ad 121 di itos. Unde cum V in cali &undo dkfignet I~<br />

in quart0 4, in B exto I6 : erit refiftentia ad pondus Globi in caCu i<br />

fecunda LX 0,0030~9~ ad 121, in quart0 wt 0,0417492 ad 121~ in<br />

fexto UT 0,61675 ad 121.<br />

Arcus quem pun&urn in. file notakm in cafu fixto defc.ripfit, *<br />

8<br />

erat s zo- ;+ $eu I 19~5 digitorum. Et proptcrca cum radius effea:<br />

F22 digitorum , & Iongitudo Penduli inter pun&urn . fufpenfianis .,<br />

& ‘_


& centrum Globi eiTet 126 digitorum, arcus quem centr~m Ghbi<br />

T)e MOTU<br />

CUR 1-0 n 03 defcriyfit erat: r.zh,i, digitorum. C&ohm corporis oMlauntis velocitas<br />

maxima, ob refiknciam Aeris, non incidit in pun6hn infihum<br />

arcus dekripti, Ced in media fere loco arcws cotius verfhr :<br />

plxc eadcm crit circiter ac ii Globus dekenfu fuo toto in Media<br />

xlon reiifiente dekriberet arcus iflius partem dimidiam digitorum<br />

GZ&, idque in Cycloidc, ad quam motum Penduli fupra redilxi-<br />

IIILIS: & propterea velocitas il!a xqualis cric velscirat


PoRea Globum plumbeum, diamktro digirorum z, St ponderc<br />

unciarum RoPnanarzkm 265, Ci rpendi f30 eodem, fit u t inter cefllw<br />

tru’m Globi 8-z puntium fifpenhnis intervallum ell’et pcdum 1043<br />

& numerabam ofcillationes quibus data motus pars amitteretur.<br />

Tabularurn fhbfkluentium prior cxhibet numerum of?ciIlaeionum.<br />

quibus pars p&ava mows totius ceffavit; fecunda numerum okcillationum<br />

qulbus ejufdem pars quarta amifi fuit.<br />

DeJenfr4s priws T 2 4 8 16 32 CL&<br />

A-~hqis dtFimus g ‘; 3: 7 14 28 56<br />

Nz4merus O&%&t. 226 228 193 r40 go? 53 30<br />

DefccpnJ;s ph?ws f 2 4 a 16 32 Gqg<br />

+dsGlpPJirS zldtimus A 12 ’ 3 6 12 24 48<br />

Nfdmerws OfXut. 51c.l 51% 420 318 204 121 70,<br />

In TabuIa priore fkligendo ex obfervationibus tertiam, quintan~<br />

& feptimam 3 82 exponendo velocitates maximas in his obkrvasionibus<br />

particulatim per numeros I, 4, x6 refpe&ive, & generaliter<br />

per quantiratem V ut fipra: emerget in obfervatione tertia.<br />

A<br />

2<br />

-ZZ A -/- B -#- C, in quinta -&<br />

192<br />

2<br />

= 4A-/-8B+IbC~ in kptimza.<br />

. $, -<br />

-.=x6A -#-6&.B-+zf6C. - Eke veru aequationes redu&x dans.:<br />

z.= o,oor++ B 5 0~00~~9.7, C= o,ooo879. Et inde prodit refifientia<br />

Globi cum Gelocirate V moti, in ea ratione ad pondus fium i<br />

unciarum z 63, quam habet o,ooop V + 0~000207 V+ + o,ooo~ijp Va<br />

ad penduli longitudinem I 2 L digitorum. Et fi Cpekkmus earn folummodo<br />

refifienciz parrem qua: efi in duplicata ratione velocitatig<br />

&ec ait ad pondus Globi ut o,ooo6gg ,V’ ad 12 I di@tos. Erat au-.<br />

tern hsc pars refifientk in experiment0 prima ad pondus Globi<br />

Jignei unciarum 57?;, ut ~30-17 vi ad I 21: & inde fit refifientia<br />

Globi lignei ad refifientiam Clobi plumbei (paribuseorum velocita-<br />

-tibus) ut 5922 in o,oozz17 ad 26$ in 030006sp, id e&i ut 7$‘ad I,<br />

iametri Globor~m *duorum want Gi & 2 dj,gitorum, & harum<br />

quadrata iiznt ad inwcem ut47t 6t 4, i'etl II-?;+ & I


2, 8 9 l?;z-l I E 0 s 0 P E-1 f AZ N h 'I- u R A L I s<br />

y?!: r\!OTrJ fkentiam Hi, qux axe perrn:~~n;-i cnr, CIC dc pendulorum ,inventa<br />

‘~~~~~~~~~~~~~~~~ reGEellfia ~~ibduci debec. WXIIC ;lcc(lrAtte $cfinire nodl potbli, fed<br />

majcxem e,Imcn inveni quam parrcn~ tcrt!:lm reGRenciaz totius minoris<br />

pcnduli j & indc didici quad refif2enck.z Globorum, dempta<br />

fili relift-entia, filnt quam proxirne in dupkata ratione diametrorum.<br />

Nam ratio 7; -f ad P -;, ku 10: ad I, non longe abelE a<br />

dixuetrorurn rarione dupliraoa xr4+ ad I.<br />

Cum refiitentia fili in Globis majoribus minoris fit momenti<br />

eencavi etiam experimenturn in GEobo cujus diameter erat 182 digicoma.<br />

Longirudo penduli inter pun&urn fufpenfionis 8t tenrrum<br />

ofcillarionis erat digitorum IZZ$, ilIter p~~~&mn fiufpenfionis<br />

tc nodurn in file 109: dig. Arcus primo penduli detienfu a noda<br />

dekriptus9 32 dig. Arcus afcenfu ultimo pofi otiiktiones<br />

quinque ab codcm nodo dc-kriptus, z8 dig. Sumtlla arcuum feu<br />

arcus rotus ofcillatione mediocri defcriptus, 60 dig. Difhmia<br />

arciium 4. dig. Ejus pars decimn feu differentia inter defcenfum Ik<br />

afcenfum in ofcillntione mediocri 5 dig. UC radius 109% ad radium<br />

1122+, ita arcus torus GO dig. ofciHatione mediocri a nodo dekriptus,<br />

ad arcum totum 67; dig. ofkillatione mediocri a centro<br />

Globi defcripcum : & ita differenti&? ad differentiam novam ~4475~<br />

Si ‘longitude penduli, manenre longitudine arcus defiripti, augeretur<br />

in ratione I 2 6 ad I 22* j tempus okillationis augeretur &velociras<br />

penduli diminueretur in ratione illa fubduplicara, maneret<br />

vero arcuum defcenfu & fubfequente akenfu defcriptorum diffe-<br />

Ten&a 0,4q.7 5. Deinde ii arcus defcriptus augeretur in ratione.<br />

a~+~+ ad 67$, differentia ifia 0,447~ augeretur in duplicata illa ra-<br />

Cone, adeoque cvaderec I~ 5295 • HZX ira fe haberent, ex hypothefi<br />

quad refifientia Penduli effet in duplicata ratione veloci<br />

tack Ergo G pendulum dekriberet arcum totum IL+& digitor.um,<br />

& longitude ejus inter pun&urn fufpenfionis & cen-<br />

,trum okillationis effet 126 digitorum, difFerentia arcuum detienfu<br />

8-z fubfequente afcenfii dekriptorum forec 1,529~ digitorum.<br />

Et hzx difkrentia duRa in pondus Globi penduk quod erat<br />

unciarum ~08, producit 318, I 36. Rurfus ubi pendulum fiperius<br />

ex Globe ligneo confiru&um, centro ofcillationis, quod a pun&o<br />

fufpenfionis digitos 126 difiabat, defcribebat arcum totum 1245<br />

digitorum, dift’erentia arcuum defcenfil & afcenfu defiriptum fuit<br />

126 .<br />

ii-F m 9$<br />

-$ quz duAa in pondus Globi, quod erat unciarum ~7:~)<br />

producit 4p,3g6- Duxi autem differcntias hafce in pondera Globoraam<br />

ut invenir.ena e0rum refiffentias, Nam differentia: ori-<br />

UllfXW


untur ex refiIfentii% fiWclue uk refifientiz dir&e & pondera ill- I, I II P x<br />

,verk. Suflt igicur refifientiti: ut numcri 3rs,~36 & 4,8,j3G. Pars SI!~VNJ~IJ*-<br />

autem refihntia: Globi minoris, qux efi in duplicata ratione ve]ocitatis,<br />

erat ad refifkotiam totam, ut 0,567~~ ad o,Gr675, id efi, LIP<br />

4~1453 ad ~9,376; & pars refiRentilr: Globi majoris yropemodum<br />

2quatur ipliu§ refifientk toti ; adeoque partes ills Cum Lx 3 18~1 gr;<br />

& 4q)4j3 quamproxime, id efi, ut 7 & L. S~mr autem GiIoborum<br />

diamctri 18; 8r 6Q 5 83: harum quadrata 3 fr;S, & 472: runt ut 7,43%<br />

& I? id efi, UC Cloborum refiltentix 7 & I quan~pmxime. IIliffkrentia<br />

rationum haud major efi quam quz ex fili r&Rentia oriri potuit.<br />

Igitur refifientiarum partcs ilh quzc hunt, paribus Globis, ut<br />

quadrata vclocitatum j ~UIIC criam, paribus vclocitatibus, ut quadrata<br />

diamecrorum Globorum.<br />

Czrcrum Globorum, quibus uftis fum in his experimentis, maximus<br />

non erat perktie Sphrricus, & propterea in calculo hit allato<br />

minutias quafdam brevitatis gratis neglexi; de calc~llo accurate in<br />

cxpcrimcnto non fatis accuraco minime iollicitus. Optarim itaque<br />

(cum demo&ratio Vacui ex his dependcat) ut experimenta cum<br />

Globis & pluribus & majoribus 82 magis accuratis Eentarencur. Si<br />

Globi fitmantur in proportione Geometrica, puta quorum diametri<br />

fiiint digitorum 4, 8, I 6, 32 ; ex progrcffione experimentorum colliigetur<br />

quid in Clobis adhuc mtljoribus evenire debear.<br />

am vero conkrcndo refifiencias diverforum Fluidorum inter f2<br />

tei!tIvi fcqucn th Arcam ligneam paravi longitudine pedum guatuor:<br />

latitudme’& al titudine pedis unius. Hanc operculo lludatam<br />

implevi aqua fontana, fecique ut immerh pendula in medio<br />

aq~m ofcillando moverentur. Globus autem plumbeus pondere<br />

1~62 unciarum, diametro 3: digicorum, movebacur ut in Tabula<br />

kqucn te dekripfimus ) exiitente videlicet longitudine penduli a<br />

pun&o fifpenfionis ad pun&-urn cyuoddam in file notatum 126 di-<br />

@torum, ad okillationis autem ccntrum x3+$ djgi!orum.


1) F bl@ T U<br />

111 eioerimento columnn: quartz9 motus ayual!s Ofcillation&u$<br />

~OIIPOI~UM 537 in jere, & 1: in aqua amifi hunt. Erant qu$em OfCillationcs<br />

ill acre paulo celeriores quam in aqua. At ii okillationes ,in aqua<br />

in ea ratione accelerarentur ut motus pendulorum in Medio utro- *<br />

que fierent zrquive!oces, maneret numerus idem okillationum 15<br />

in aqua, quibus mows idem ac prius amitFeretur;* ab refifientiam<br />

auaanl ;~t fimul quadrarum tetnporls.dlmlnutum .ln eadem ratione i<br />

illa duplicata. Paribus igitur pendulorum velpclt?tilys ftlorus z-<br />

quales in aere oMlationibus 53 5 & in aqua ofilll;ttlotllbus xf amifli<br />

iilnt; ideoque refifielitia penduli in aqua efiad eJus refifientiam in<br />

acre ut 535 ad I$. Hzc efi proportio refifientiarum totarum in<br />

c;lfu columnar quartz<br />

Defignet jam A V + C V’ diff’erentiam arcuum in dekepfii & f”&<br />

fequente afcenfu defcriptorum a Globo, 111 Acre cum velwtate maxima<br />

V moto j ,& cum velocitas maxima, in Cab COlllllX~~ quartz, fit ;<br />

ad velocitatem maxham in cafu columntl: primx, ut 1 ad 8 ; & diffe- I<br />

relltia illa arcuum, in cafu-columnar quartz, ad difFerentiam ,in cafu<br />

2<br />

colummz prima2 Ot - ad ‘IG ku ut 855 ad 4280: fcribamus in<br />

535 Q?<br />

his cafibus T & 8 pro velocitatibus, atque 85+ & 4280 pro differeritiis<br />

arcuum> & fret A -+-Cc 85; & 8A-t.G4C=4280 tiu<br />

A + 8~ = 53 5; indeque per redu&ipndm aquationum proveniet<br />

7 C = 449: & C= 64;?-, & A= zl+ : atque adeo refintentia, cum<br />

fit ut ,2, AV+-$ CV’, erit ut 13AY+4JlS5Vt. Qareincal’u coluinriz<br />

quartz, ubi velocitas erac I, refihntia tota efi ad gartem,<br />

Gain quadr;ito velocitatis proporiionakm ) ut I 31”; + @A feu<br />

6 I+: ad 48 j5 j ‘& idckco refifientia penduli in aqua efi ad refillentiz<br />

parteq illam in tiere c$m quadrato vclocitatis proportiohalis<br />

efi, quzqbe fola iti motibtis velocioribus cotifideranda venit, ut 6x4:<br />

ad 48rs-& 535 ad of conjun~im~ id efi, ut 571 ad I. Si penduli<br />

in aqua ofcilltiiitis “fi’luh totdm fuiffet ihinerfiln, refiitentia ejus<br />

fuiffet adhuc major; adeo ut pend,uli in aere ofcillantis refifientia<br />

illa quz velocicati$ qtiadraco ‘propbrtionalis efi$ quxque iij1.a’ in<br />

corporibus velocioribus conkieranda venit, fit, ad refiiten@n ‘cjtifdem<br />

phduli totius, ,eadem cum .veloditate, in aqua ofc&y~th~<br />

ut 800 vel goo ad I. circiter, hockfi, ut de&as aquzad denhaeatem’<br />

aeris quampr.oxime.<br />

In hoc calculo fumi quoque deberet p$ks *illa, refi,fknria: ‘petihli<br />

15 aqua,-quaaeffit ‘tit quadraturn valocita‘ti’s,?fed (+@od wiiitim for-,<br />

te videatur) refifientia in ajlta ~@kur ain &iotie whrirdtis<br />

pluG


PRI:NCI.P3eA MATHEhfATPCA. 231<br />

plufquam duplicata. Ejus rei caufam invefiigando, in hanc in- LIIIFX<br />

cidi, quod Arca nimis angufia. effet pro magnitudine Globi pen- SEC~E:D*~~<br />

duli, & morum aqua cede& pram angufiia fua nimis impediebat.<br />

Nam ii Globus pendulus ) cujus diamerer erat diski u-<br />

n&s, immergeretur j refiflentia augeba tur in duplicata ratione ve-<br />

Iocitatis q,uam proxime, Id tentabam conitruendo pendulum ex<br />

Globis duobus, quorum inferior 8z minor ofcillarerur in aqua, iir.<br />

perior & major proxime fupra aquam file affixus efit, & in ACTc<br />

ofcillando, adjuvaret motum penduli eumque diutarniorem redder-et,<br />

Expcrimenra autem hoc modo infiituta fe habebant uc in Tahula<br />

fequente defcribitur.<br />

Arcus defcenfu prim0 defcriptus 16 8 4 2 I ‘; 2<br />

Arcus u/Zenfii dim0 defcripw 12 G 3 If i $ L,<br />

Arcmm dz$motzki amifoproport. 4 2 I z ' ; f Iiz<br />

.i%merzu Ofcilhtionzkm 3;. 6f IZ,", 21: 34 53 6r$<br />

Conferendo refiflentias Mediorum inter fe, effeci etiam UE pendula<br />

ferrea ofiillarentur in argento viva. Longitudo fili ferrei erat<br />

pedum quaG trium, 8~ diameter Globi penduli quail tertia pars digiti.<br />

Ad filum autem proxime fupra Mercurium affixus erat Globus<br />

alius Plumbeus fariS magnus ad motum penduli diutius contix3uandum.<br />

Turn vafculum, quad capiebat quail Iibras tres argenti<br />

vivi, implebam vicibus alternis argento vivo & aqua communi, UC<br />

pendulo in Fluido urroque fuccef&e okillante, invenirem propor-<br />

&onem refiitentiarum : 8r prodiit refifientia argenti vivi ad refifientiam<br />

aqua, ut, 13 vel I+ ad I circiter : id elt, ut denlitas argenai,<br />

vivi ad denfitatem aquz Ubi Clobum pendulum paulo majorem<br />

adhibebam, puta cujus diameter efit quail f vet : partes digiti,<br />

prodibat refifientia argenti vivi in ea ratione ad refifientiam<br />

aqua, quam habet numerus, I 2 vel IO ad I circiter. Sed ex,perimento<br />

priori magis fidendum eit, propterea cpod in his ultimis<br />

Vas, nimis angufium fuit pro magnitudine Globi immerG. Ampliato<br />

Globe, deberet edam Vas ampliari. Confiitueram quidem<br />

Ilujufinodi experimenta in vafis majoribus & in liquoribus turn<br />

Metallorum fuforum 3 turn aliis quibufdam tam calidis quam fri-<br />

@d is repetere : kd omnia experiri non vacat, & ex jam dekriptis<br />

&is liquet refifientiam corporum celeriter motorum denfitati Fluidorum<br />

in quibus moventur proportionalem efk quam proxime.<br />

Non, c&c,0 accurate. Warn Fluida tenaciora, pari denfitare, procul-<br />

PI? 2<br />

dubio


232<br />

I?n F,ToTu dubi magis refiitunt quan liquidrom ut CNeum frigidurn quam<br />

Con~orto~ &idum, caliduln quam aqua yluvidis,, aqua qU”M Spiritus Vini,<br />

verum in liquoribus qui ad ~CII&III f%tls fluidi hot, UC in Acre, in.<br />

~~~~ feu dulci fiu falfa, in Spiritibus Mini, Tcrebinthi & Saliuln,<br />

in Oleo a fxcibus per defilllationem liberato & cakfa&o, Oleoque<br />

\litrioli ~fk Mercurio, ac Metallis liquefaflis, 8~ fiqui Gnt alii, qui<br />

tlm fluidi fint ut in vah agitati mown imprerum diutius con.<br />

fervent, effufique liberrime in guttas decurre+o refolvantur, nu]-<br />

lus dubito quin regula allata fatis accurate obtmeat : prazkrtim fi<br />

cxiTerimenta in corporibus pendulis 8~ majorlbus Pz velocius motis<br />

inftituantur.<br />

Denique cum receptiilima Pl~ilofophorum rucatis hujus opinio<br />

fit, Medium quoddam aethereum SC longe ~ubtilifimum extare,<br />

quad omnes omnium corporum poros SC meatus liberrime permeet;<br />

a rali autem Medio per corporum poros fluente refifientia<br />

oriri &beat: ut tentarem an refifientia, quam in motis corporibus<br />

experimur, tota fit in eorum externa fiuperficie, an vero partes etiam<br />

internrr: in fuperficiebus propriis refificntiam notabilem fintiant,<br />

excogitavi experimentum tale. Filo pedu,m undecim longitudinis,<br />

ab unto chalybeo Otis firmoP mediante annul0 chal beo, h.<br />

fi>endebam pyxidem abiegnam rotundam, ad contlituen CT um pendulum<br />

Iongitudinis prazdi&ta. Wncus furfim przacutus erat acie<br />

concava, ut annulus arcu fuo fuperiore aciei innixus liberrime mom<br />

veretur. Arcui autem inferiori anneaebatur filum. Pendulum ita<br />

confiitutum deducebam a perpendiculo ad difiantiam quail pedum<br />

fix, idque fecundurn planum aciei unci perpendiculare, ne annuhs,<br />

ofcillante pendulo, fupra aciem unci ultro citroque laberetur,<br />

Nam pun&urn fiufpenfionis, in quo annulus uncum tangit, immotum<br />

manere debet, Locum igitur accurate notabam, ad quem de0<br />

duxeram pendulum, dein pendulo demiiro notabam alia tria loca ad<br />

qua redibat in fine ofcillationis prim%, kcunda ac tertia. Hoc re-.<br />

petebam &Pius, UE loca illa quam potui accuratifflme invenirem.<br />

Turn pyxidem plum bo & gravioribus, qw ad manus erant, me.--<br />

tallis implebam., Sed prius ponderabam pyxidem vacljam, una<br />

cum parte fli qua: &cum pyxidem volvebatur ac dimidio part%<br />

=liqux que inter uncum & pyxidem pendulati tendkbatur.<br />

(Nam fhn tenfum dimidio ponderis fui pendulum a perpendiculo<br />

digreflum fernper urget.) Huic ponderi addebam pondus A’eris<br />

quem pyxis capiebat. Et pondus totum erat quail pars.feptuage-<br />

6ma.okha pyxidis metalllorum plenx, Turn quoniam pyxis meallorum


Cn?IA MATHEMATIcA.<br />

“93<br />

tdlorulu plcna 3 pondeye ho tendelldo filum, augcbat Iongit&i- LIT3Eii<br />

Jlern pcnduli, contrahebam filum ut l)enduli j3t-n o&h-&s eadem SE~TJNIJLJ~+<br />

efit longitude ac prius. Ikh pendulo ad locum prima notarum<br />

uetra&o nc dimiffo, numerabam o~illationes qunfi fkptuaginta &<br />

Eeptem, donec pyxis ad locum fecundo notatum rediret, totidemque<br />

fubindc dotlee pyxis ad Iocum tcrtio notntum rediret, atque<br />

rurhs totidcm do1lcc pyxis rediru ho attjngeret locum quartum.<br />

Wndc conclude quad refifientia tota pyxidis plcnz flon majoren<br />

hab~bat proportionem ad refiflentiam pyxidis vacua quam 78 ad<br />

77. Nnm fi zqualcs effcnt ambarum refifienrizc, pyxis plena oh.<br />

vim hnm infitam feptuagics & o&ics majorem vi infita pyxidis<br />

vacutr, morum hum ofhllatorium canto diutius confervare deberet<br />

) atque adeo compleris t&per ofcillationibus 78 ad loca ilta.<br />

notata redire. Rediit x.lrcm ad eadcm completis okillationibus 77.<br />

Deii.guct igitur A relificntiam pyxidis in ipfius fh’upcrficie exter-.<br />

na, & 13 rcfificntiam pyxidis vacua in partibus internis; & ii rcfifientix<br />

corporum zquivclocium in partibus internis fint ut materia,<br />

fcu nwmerus particularurn quibus refifiirur: erit 78 x3 refiftentia<br />

pyxidis plcn;r: in ipfius partibus intcrnis: adcoque pyxidis vacux<br />

rcfiitcntia tota A +-B erit ad pyxidis plenaz refif’knciam totam<br />

A +78 W ut 77 ad 78, & divifim A +B ad 77 13, UC 77.ad I><br />

indcque A + B ad I3 ut 77 x 77 ad I, & divifim A ad B ut 5928<br />

ad x. Efl: igitur refifientia pgx,idis vacurr: in part&us internis..<br />

quitlquies miliies minor quam ejufdem refifientia in cxterna fiperficie,<br />

& amplius. Sic vero difjjutamus ex Hypothefi quad major<br />

itia refiitentia pyxidis pkn~, non ab alia aLqua caufa latente<br />

oriatur, fed ab aE$one fola Fluidi alicujus fibtilis in merallum..<br />

iJ.lClUi-hl*<br />

J--Jot experimenturn recitavi memoricer. Nam charra, in‘qua il:<br />

Jud alliquando defcripkram, intercidit. Wnde fra&as quardam nu+merorum<br />

parteS ) quz memoria exciderunt, omittere compulfiie~,<br />

fum. .F=Jam omnia dcnuo tenrare non vacat. Prima vice, cum un-.<br />

co infirm0 ufus effem, pyxis pkna citius retardabarur. Caufam<br />

quErendo, reperi quad uncus infirmus cedebat ponderi py$dis, &c<br />

ejus ofiillationibus obkquendo in paws omnes AeQebaturO arae.<br />

barn igitur uncum firmum , ut: punRum fXpenfionis immorum m2h.<br />

zIGret & tune cmnia ita. evenerunt: uti Eupra dei’cripfimus.


!%‘~oPOsITIO XxX11. THEO:REhl‘A XXVI.<br />

Corpora fimilia. Q- fi,militer &x1 tempoGbus proportion,ali4us inxer<br />

fe fimiliter moveri dice, quorum fitus ad iwicem in fine rem-<br />

m&3’, cum a!t$rius partdculis correfpogdentibus conferatltur,<br />

de te,m.pora erunt proyorriwalia, in quibus fimiles 8s proportion+<br />

Ies, Figurarum fimilium partes a particulis corrc@ondentibus d,e..<br />

kribul? tur. Jgitur ii duo ht ejufmodi Syfkmata~ particulll: carrefpqnden,tes,<br />

05 fimilirudincm incx,ptorLjm m,otuum, pergent% fi,<br />

Aliter moveri ufque, donec fibi rn~ut~~o occurrant, Nam 4 nullis<br />

agltantur.viribus?%rogredientur uniformiter in.lineis r&is per mo-<br />

;$us ,Leg. T. ‘2; v~rrbus aliqu”ibus.k mup~o agitant, & yires illx finr:<br />

-ut particularum correfpondentium diametri inverfe & quadrata velocitatum<br />

dire&i* quoniam particularurn &us funt firnile & vires<br />

.proportipnales, vlres tota: quibus particule correlrpondentes agi-<br />

:WXUt~3 cX vlrlhls fiIlgUlls +$tantibus (,per Lcgum Corollarium


PRINC’XPII;cI M.ATMEMATIc~. 295<br />

fecundurn ) compoh ) fimib hbebunt detci’minationes, perin- GIBER<br />

*de.ac fi ctntra inter parciculas fimiliter fita re.fi?iCerC$nt j & erunt sECU NDu%<br />

vires illx totx ad inviccm ut vircs fingulx componenEes, hoc efi,<br />

,ut correfpondentium particul~rum dlametri in-clerk, s;: quadrata<br />

9velocitatum dire&e : 8~ propwrea efficient ut correfpondentes par-<br />

“ticulx figuras fimiles defcribere pergant. Hxc ita fe habcbunt per<br />

Coral. I.~ & 8 Prop. lvr Lib. I. di mode centra illa quiefcant.<br />

Sin moveantur, quoniam ob tranflationum fimilitudinem, fimilcs<br />

,Mane.nx eorum fisus inter Syfiematum particulas; Gmiles inducentur<br />

mu&ones in figuris quas particuls defcribunt. Similes igitur<br />

Grunt corre$ondentiw-n & fimilium particularum morus UCque<br />

ad occtirfus 1110s primes, & propcerea fimiIes occurfus, & fimiles<br />

.reflexiones, ‘8~ fubinde (per jam oiienfa) fimiles mows inter<br />

fe donec iterum in fi mutuo inciderint, & Gc deinceps in in-<br />

corpora duo quxvis, -qux fimifia fint & ad<br />

.Syfiematurn ~pa~iculas correfpondentes fimiliter fita, i,nter ipfas<br />

.t~~poribus -pgoporYioii$libus fimilieer mov.eri incipiant , fintque<br />

earutfl .tiw@udi-nes kz denfieates ad invicem UJ magnitudines ac<br />

den~t~tes:corre~~olldentium particularurn : haze pergent temporibus<br />

.p~6porcionalibus kniliser .moveri. Eil enim eadem ,.racio pnrtium<br />

majorum Syflematis utriucque atque particularum,<br />

Coral. 2. Et fi fimiles & fimiliter pofitx .SyRematu.m partes om-.<br />

nes quiefcant inter fk: & earum &x,.-qua cxteris majores lint, &<br />

*$bi mutuo in ucroque Syfiemate corre’fpondcant, kcundum lineas<br />

fimilirer ?i tas:$$ cum qotu u wunque maveri incipian t : hx iin&s<br />

fn :I$@+ ~yft;etnih~& ptiidus exkitabrnt motL!s, &,pergent<br />

inter ipfis ty@orikys prqp‘ortionalibus~ ,fim&ter moveri> argue.<br />

adeo fpatia &+nietris fiuis praportionalia defcribere.<br />

p R OP.0 S I T I 0, -~X~II~.<br />

‘YF- H E 0 REM e XXVII.


y,, ‘i ;,: > -; 6 i<br />

I)riol*iS<br />

a\ltem gc”crjs rciiLh3lt.k f%nt ad invkem ut v&s to&? IIICIcw4<br />

!‘dl, i’ ~1 Criccs a qu~l.~us oriilntur, 1 ‘d elk, ut vires totz acceleratrices & quanrlrnCcs<br />

tll:accri;c in partibus correipondentibus; hoc efi (per Hytli,,t~lclin)<br />

Ilc quadracrz velocitatum dir&k & diftantiz particuh-<br />

;lllll c~trr~l~~~*~dc~l~illn~ inw3-fc & quancirares mare& in partrbus<br />

coi-r~lj,~nde~~tii~~s dm&e : ideoque (cum difiantk particularum Sy-<br />

I$C~~~IS unius fint ad difiatrrlas correi@ndentes pmhkmm ahrlw5,<br />

Ilt Jiamcrcr particula: vel partis in Syfiemate pricxe ad diametrum<br />

particulru vel partis correrporldentis in aho, & quantita-<br />

KS m3ccri:C hc UC denficates partium SC cubi diametrorum) refii’rcntr;t”<br />

liwc ad invicem ut quadrata velociratum & quadrata diam~twrum<br />

& denfitarcs parcium Syltematum. $i$ E. 59. Pofierloris<br />

gcncris refit?entia iunt ur reflexionum correfpondentium nu..<br />

mc;i & h-es conJuwCtim. Numeri autem reflexionum funt ad in.<br />

viccm ut velocicates parrium correfpondentium dire&e, & fpatia<br />

~nrcr edrum reflexiones inverk. Et vires reflexionum fint ut ve-<br />

!ucic;iccs & m~gnitudines & detlfitares partium correijpondentium<br />

conjun~im ; sd eR, ut velocitates & diatietrorum cubi & denfit&<br />

.ses parrium. Et conjunQis his omnibus rationibus, refi&nt&<br />

pwtium correfpondentium funt ad invicem u t quadrata v&-gil<br />

wn 8~ quddraca diametrorum<br />

CC Iii. 53.<br />

SC denfitates partium conjun&im,<br />

COW’. r. -Igitur ii Syfiemata illa fint Fluida duo EIafiica ad<br />

nwdwm Aeris, Ss partes eorum quiefcant inter fk: corpora autem<br />

duo iimilia & partibus Auidorum quoad magnitudinem & denfitarem<br />

proportionalia, & inrer partes illas fimiliter yofita, kcundum<br />

Iineas i&liter pofiCas Ltcunque twoiiciantur : vire? -- -- aute!nl ---_-_- acce-<br />

‘hatrices, quib& particuk Jhidbruh Ce mu&o. a&tank.. -^-‘J ikit ut<br />

corpvrum projeQorum diametri: .inverfe, 8~. tiuadra’tt T Aocitatum<br />

dir&o : corpora ilfa temporibus prOporcinn;lihrl-~,n;lpn<br />

hnt motus in Fluid& SL. fpatia fimilia ac : diamfwis __-_____- fuis proportionaha<br />

dcfcriben t.<br />

Gor@l. 2. Proinde in codem Fluido projeEtile’velox,re~itenriam paritur<br />

quz 4% in duplicara ratione velocitatis quam proxime,<br />

Nam<br />

G vires, quibus particulz difiances k lnutuo agit+nt, augerenttir in<br />

duplicata ratione velocitatis, refifientia fokt in’&&m ratione duphcata<br />

acwace 5 ideogue in Media, cujus partes ab invicem difian~<br />

ocs fcfe viribus nullis agitaqt, refifientia .ef% in duplicata Iratione vec$$i<br />

accurate. Sunto sgitur Media kria A, .L?, C & p&bus<br />

mhhs a aqudibus Lk fccundum diRantias azquales regulariesr<br />

i<br />

diSp&


dlfpofitis confiantia. Partes Me&rum A & B fuviant fc muruO<br />

virlbus purr: fint ad invicem ut r & Y, illrr M~~ii c ejufino- s ,,“LYT,‘ks.<br />

di viribus omnino defiituantur. Et fi corpora quaruor azqualia<br />

‘fD, E, p, G in his Mediis moveantur, priora duo a 8~ E in prioribus<br />

duobus A & B, si: altera duo F & G in tertio c j Gtque velo&as<br />

corporis 2) ad velocitatem corporis E, & velocitas corporis<br />

F ad velocjtatem CQrppriS G, in fubduplicats ratione virium ‘r<br />

ad vires Y: refifientia corporis I) et-it ad refifientiam corporis E,<br />

8~ refifientia corporis F ad refiitentiam corporis G, in velocitatum<br />

ratione d&plicata ; 6-c propterea refificntia carporis ‘I> erie ad r&i-<br />

Fi;“;i”rn corporis F ut refifientia coypork E ad refifientiam corpocorpora<br />

f73 & F zqulvelocia UC & corpor;l E & Gj<br />

• Su•to<br />

& augendo velocitatcs corporum ‘9 & Fin ratione quacunque, ac<br />

diminuendo vires particularurn MediiB in eadem ratione duplicata,<br />

accedet Medium B ad formam 8~ conditioner-n Medii c pro lubihu,<br />

& id&co refifientiz corporum zqualium & aquiveIocium E<br />

& G in his Mediis, perpetuo accedenc ad zqualitatem, ita ut ealrum<br />

differentia evadat tandem minor quam data qurevis. froi+e<br />

@Llrn refifien tia corporum 2) & F’ fint ad invicem UC reiiltentiaz corporum<br />

E & G, accedent etiam haz~fimiliter ad rationem aqualitaais.<br />

Corporum igitur D & F, ubr.velocrfime moventur, refifienti&<br />

.Sunt: aequales quam proxime : & propterea cum refifientia corporis<br />

8 fit in duplicata ratione velocitatis, erit refif’tentia corporis<br />

52 inpa&zm ratione quam proxime.<br />

pIg& lgitur corporis in Fluid0 quovis Elaltico velociffrme<br />

?rrii?ii fere eit: refifientia .ac ii partes Fluidi viribus fuis<br />

ceutrifugis defiituerentur, feque mutuo non fugerent: G modo<br />

Fluidi vis Elafiica ex particuIarum viribus centrifugis oriatur, &<br />

velocitas adeo magna fit ut vires non habeant Otis temporis ad<br />

agendum.<br />

CQ&. 4. Proin& cum,,refiRentia fimihum & aquivelocmm cotporbm,<br />

in Media cujus partes difiantes k mutuo non fugrunt, fint<br />

ut quadrata diametrorum 5 funt etiam aquivelocrum & celerrime<br />

nnotorum corporum refifientiz in Fluid0 Elafiic? ut quadrata<br />

diametrorum quam proxime.<br />

co,&, 5. Et cum corpora fimiha, zquaha 6- SquiVelock in<br />

Mediis ejufdem den&G, quorum partida: fe MUtUO non fUgiunt,<br />

five particuls ik fint plures & minores, five paucloref tk<br />

majores, in zqualem materig quantltatem temporlbus aqualrbus<br />

i+r~gant, eique aqualem m quantitatem imprimant, & viciffh


DE MOTU<br />

ConPoRu~~I.


PRINCIPHA MATHE~~~ATI[cA, 233<br />

mittantur perpendiculares B E, a> L, & vis qua particula hledii, Llnl?X<br />

fkcuadum re&am FB oblique incidendo, d;iobum ferit in 6, eritS~cr$: DVS.<br />

ad vim qua parcicula eadcrn Cylindrum 43 .NG;,Q\ axe AC I circa<br />

C_;lobum dekripttm~ perE”e”dicularitcr feriret in L, ut LD ad<br />

I, B vel B E ad 8 C. Rurfits eflicacia hujus vis ad movendum<br />

Globum fecundum incidentisfiw plagamE’~3 -vcl AC, efi ad ejuI:<br />

dem efficaciam ad movendum Globwn kcundum plagam decerminationis<br />

f%s, id cfi, hzundum plagam r&x BC qua Globum dire&e<br />

urger, ut B E ad Be. E.r: conjirdl-is rationibus, effkacia<br />

particulx, in Globutn kcundum ~&am F B oblique incidentis, ad<br />

xnovendum eundem fecundurn plagam incident& hz, et? ad efficaciam<br />

particuh ejufdem fecundum eandem re&am in Cylindrum<br />

perpendicuhiter incidentis, ad ipfium movcnduril in plagam eandem,<br />

ut BE quadraturn ad BC quadraturn. Qare fi ad Cylindri<br />

balm circularem NAO erigacur perpendiculum b HE, & fir<br />

BE quad<br />

b E aqualis radio AC, & b H 3zqualis -c-T: erit bHad bE<br />

ut eEe&us particula in Globum ad effe&um particula in Cylindrum.<br />

Et proptcrea folidum quad $ reBis o’mnibus b N occupatur<br />

erit ad folidum quad j re@is omnibus b E occupatur, ut<br />

effe&us particularum omnium in Globum ad effe&um parricyT<br />

hum omnium in Cylindrum. Sed folidum prius eft Parabolors<br />

vertice C, axe CA Sr here retio CA defcriprum , & {olidum<br />

pofierius efi Cylindrus Paraboloidi circu’mkiptus: & noturn k!.I<br />

quod Parabolois fit femifis cylindri ; circirrn$rtipti: Ergo VIS<br />

rota ,.Mtidii ‘in ‘GlobtiiPn eR dupIo,~hinor c!pra,m’+hdem vis tota<br />

i:n Qlindrum, Et propterea fi partickhz~ Medii quiefc&ht, 8-z<br />

cylindrus zc Globus tiqukli cum velocitate moveieritub, foret refifientia<br />

Globi duplo minor quam refitientia Cylindri. L&B. 59.<br />

. ! : ( Scbolium.<br />

. ‘<br />

~~~elrlm~iEibd~ i;~~~r~-iliaE int~r.~Ce.ii;lol,, c: 1 . ’)’<br />

.d& t;&$&&&i* c*m’ja&,,a, jj


30s PEIILOSOPMI~ NA<br />

nz MOTV axis ~1; vcrfus 13 progredientium frufiorum nlhirne refiitatur : bi-<br />

C-OR ~011 UM feca altitudinem 0 2) in R& produc 0 2 ad S UC fit $&S squalis<br />

gC, & erit S vertex cConi cujus frufium quaeritur.<br />

Unde obirer, cum angulus C’SB iernper fit acutus, conkquens<br />

efi, quad fi Eolidum ADB E convolucione bgurx Elllpticz vel<br />

Q)v&sADBE circa axem AB h&a genererur, & cangatur figurn<br />

generans A re&is tribus FG, GH, kiI in pun&~s 8; U 6r 1, ea<br />

]ege Ut GH fir perpendlcuiaris ad axcm in punL?o contaLCtus B,<br />

& FG, HI cum eadem GH contincant anguIos FGU, BSXI<br />

graduum 13 5 ‘0 folidum, qwd convolutionc figurle ~2~52 J’GHI&<br />

circa axem eundem CB generatur, nzinus retifiirur quam iblidum<br />

prius; fi modo utrumque fecundurn plagam axis hi AB progrcdiatur,<br />

& utriufque, terminus B pracedac. C&at-n quidem propofitionem<br />

in con.Bruendls Navibus non inutilem futuram cff k ccnko, 1<br />

Qod fi Figura 59 NFG<br />

ejufmodl fir curva UC, ii ab<br />

ejus pun&o quovis N ad<br />

axem AZ3 demittatur perpendiculum<br />

NM, & A pun-<br />

&o dato G ducatur re&a<br />

GR qua2 parallela fit re&az<br />

&warn t an g enti in iIT, &<br />

‘axem prod&urn &et in<br />

..I?, fuerit MN ad G R ut<br />

GR cub ad +BR,x.GB~:<br />

xc<br />

Solidurn quad. figuraz hujus revolutione circa axem A&% faQa de.,<br />

fcribitur, 10: Me&o. raro praedrtio ab A verfus B movendo, minug<br />

refifietur quam ahd quodvis eadcm. lorigitudine & latitudine defiriptum<br />

I Solidum circuhre..


PRINCII’IA MATHEM.ATIcr:A, 30r<br />

Q&bus vel Cylindrus incidir, vi rcflexionis quam maxima rcfiliant.<br />

it cum refiflentia Globi (per Propofitioncm noviffimam) fit duplo SE’~:::“P~~IJS.<br />

minor quam refiiteatia Cylindri, Sr Globus fit ad Uylmdrum ut<br />

duo ad tria, & Gylindrus incidwdo pcrpendiculariter in particulas<br />

jpfifquc quarn maximc rcfleCtcndo, duplarn fui ipfius vctocitatcm<br />

ipiis commur~icet : Cylindrus quo tempore dimidiam longitudinem<br />

axis iui dckribit communicabit mown particulis qui fit ad torum<br />

Cylindri motum ut dcrlfitas Medii ad denfitacem Cylindri 5 & Gtobus<br />

quo tempore totam longitudincm diamecri fief dei‘cribit, corn..<br />

municabit mown cundcm particulis; & quo tcmporc duas tcrtias.<br />

partcs diametri he dekribit camnwnicabit motum PwricuIis qu.i<br />

iit ad totum Globi mown ut denfita~ Mcdii ad deniitntcm Globi.,<br />

Et proptcreaGlobus rcfiitentiam patltur clua fit ad vim qua totus,<br />

ej\ls motes v.cl auferri pofit ~1 generari quo tempore duas, terrias,<br />

partcs diamctri fuzz deicribit,,, ut denfitas Medii ad denjitatcm<br />

Globi,<br />

C&J. di Ponamus quad, particulx Mcdii in Globum vel Cylin-+.<br />

qJrum9inciden tes .non refI&antur i &: Cylindrus incidcndo pcrp~~<br />

&&riter in part&h fimpiicein fuam whcitatcm ipfis .commu~<br />

n&bit,. ideoque rcfiflentiam patitw duplo minorcm quam* in priore<br />

cafil, & refifientia Globi crit ctiam duplo minor~quam, prius.,<br />

&J. 3d Ponamus, quad particuIz.Medii vi rcflexionis ncque m;z- I<br />

xima neque nulla, fed mediocri aliqwa refihant a Globe 5 & rcfiz<br />

fientia Globi erit in cadem ra tionc smcdiocri irl ter rcfifientiam im:<br />

prim0 caCu & refifienti;\m.in f&undo. 4,-g, 1,<br />

Coral. I. Ehc fi.Cllobus & parcicula Gut inkhire. dura* .& vi omni’<br />

elafiica & propterea etiani vi’ omni rcffkxionis dcfiicuta: re;<br />

fifienda Clobi erit ad vim qua totus cjus mows vel auferri pofic~<br />

vel gcnerari, quo tempore Globws qxratuor terclas partcs .&am&:.<br />

fin dcfcribic, ut ,.d.enGtas,Medii ad ldenfitarem Globi+<br />

Cord. z. Refifieqtia Globi:,. cxteria. paribus, efi in duplicara ,r;kn<br />

tione valocithsr<br />

C~~QZ, 3. Refifientia Globi, ( cxtcris parihs,. efi in dup+ata. ram<br />

Gone diamctri.<br />

CO&. 4.” Refifientia Globi, cateris paribus, CR ut dcnfitas &jed$,<br />

Cwol. f* ReGfientia Globi efi in rationcquz componitur ex dn4<br />

phta ratiome velocitatis~ &, dwplicata, ratiome diametri, & ,ratione,<br />

etenfitatis Mediii


i cum ejus refiflentia fit expoili pots@,<br />

1)~ MOTU<br />

CD~PORUM Sit AB tempus quo Globus per reiikntiam ~‘IXUTI ur$krmit& ,conq<br />

tinuaeam toeum Iixim IllOtLlill amittere<br />

potefi. ACT AB erigantur per- \<br />

~~IKI~CL~ZI AD, LK. Sitqw BC<br />

IIIO~US ille tow, & per pLmfiUln C<br />

Afymptotis Aa, AB dekribatur<br />

Hyperbola CF. Producatur .h’B ad<br />

pun&turn quodvi Erigatur pcrpendiculum<br />

E I+ erbolx occurrens<br />

in F, CO arur parallelogrammum<br />

CB E G, 8-z agatur A’$’<br />

ipfi B C ‘occurrens in ~7. Et ii Globus ternpore quovis BE, motu<br />

G-10 prima B C uniformiter continuaro, rn Medio non refifiente defcribat<br />

I‘patium C B E G per aream qaralleIogrammi expofitum,‘idetn<br />

in Media reiiitente deknbet fpatmm CB E J’ per aream JJyperbolaz<br />

expoficum, & motus ~JUS 111 Fne temporis illius exponetnr<br />

per Hyperbok ordinatam I3 F, amifi inow* ejus .parte f?C,. JQ<br />

refiitentia ejus in fine temporis ejufdem e etur per longitu&.<br />

nem BH, amiffa refifientiat: parte c’& nt hEC omnia per<br />

Corol. I. Prop. v. Lib. 11.<br />

, -(I:<br />

Coral. 7. Hint fi Clobus tempdre ‘J’ per refiitentiam w uniformiter<br />

continuatam,amittat motum hum totum A4 : idem Globus tern.,<br />

pore t in Media refifknte, per refiltentiam Rin duphcata veloeitatis<br />

,ratione decrefcentem; amittet motus iii JM partem<br />

’<br />

TT--y<br />

tM*.<br />

maninte’<br />

- I-<br />

TM<br />

parte Tp‘cc,9 & d&crib&, fpatium guod -fit ad ,&pa&n;, moru yni-


ncrari quo tempore Gfobus duas tercias diamecri Iiu3: partes, ve- LIBER<br />

Stare uniforrniter continuata defcribac, UE denfitas Medii ad SEC”ND”S*<br />

nfiearenl Globi, fi mode Globus & parcicuk hIcdii fint iilmme<br />

Utica & vi n7axima reflefiendi polleant: quodque hc vis fir<br />

plo mhor ubi Globus & particulz Medii hunt infinite dura &<br />

refleaendi prorfus delticuta. In Mediis autem continuis qualia<br />

it Aqua, Okurn calidum, & Argentum vivum, in quibus Globus<br />

n incidit immediate in omnes fluidi particulas refifientiam gene-<br />

,tes, kd premit tanturn proximas particulas Sr hx premunc alias<br />

hze alias, refifientla efi adhuc dupio minor. Globus utique in<br />

ufmodi, Medlis fIuidiffkiis refifienciam patitur quz elt ad vim<br />

z totus, ejus motus vel tolli poflit vel generari quo ternpore,<br />

tu it10 urliforrniter continu,ato, partes o&o tertias diametri fuu;l:<br />

kribatj ut denfitas Mkdii ad denfitatem Globi. Id quod in k-<br />

:ntibus conabimur oftendere.<br />

:it AC522 B vas cylindricum,. AB ejus orificium dilperius3 .CZZJ<br />

dum horizonti par$Jelum,, E F fbramen circuhe in medio<br />

di, G cent rum. foraminis,’ ,&T-G H axis cyIindri”horizooti~ pwidicularis,<br />

Et .‘concipe-c~l;i~d~urn-‘E;la~<br />

A 1> RB ejufdem cfk, latituditiis<br />

I cavitate vafis, & axem; lundeti ha-<br />

3, & uniformi cum mOtu perpetuo<br />

:endere, 6~ partes ejus quam. primum<br />

nguni fu@erficiem AB Iiq~lefkre, &<br />

quam converfis gravitate fua defluere,<br />

as5 & catara&am vel c;alumnam aqua2<br />

1 NFE N1 cade’ndo f%kya& & per<br />

men E F tranfire, idemque adkquate<br />

lere. Ea vero fit uniformis velbci-<br />

$a&$‘* ‘dWIebdentis tif &A aqua con-<br />

ZE in cik”c&6 2’B;‘quam aqua caden--<br />

SC cz$i I-ii.0 detiritiendo akicudinem<br />

acquirkre pot&,; 82 jaceaiii? 1+H Sr HG in dir&urn,, &. pet+<br />

&uni: Izducatur re&a K 2; h@izonbi praUeIa. & lateritius ,gla- _


mode d&metros re6k dimenh fiim. Parabam utique lamiia& E I I3 P. It<br />

pkmam pcrcenuem i! mcdiq perforatam, exifhytx circuhris fora.. secu ~uu6‘<br />

minis’ diarnctro partlum qumque otiavarum digiti. Et ne vena<br />

aqua exilientis cadendo aecckraretur & acceleratione redderctur<br />

angixlIiorP ham iaminam non fundo fed lntcri vafis affixi Cc, II@<br />

vena illa egrcdcretur kcundum lineam hc4rizonti parallelam. &in<br />

ubi vas aqu;w: plenum effet, aperui fornmw ut aqua efllueret; &<br />

veil,?: d$yecer, ad diflantiam quafi dinaidii digiti 3 foraminequam<br />

accuratlhme menhrata, prodiit partium viginti & unites quadrag&-<br />

Marurn digiti. hat igitur diameter foraminis hujus circularis a$<br />

diamctrum VCYKIZ ut zf ad ZI quamproxime, Per experimenta vero<br />

WntIat quad quanriras aquz qutr: per foramen circulare in fundo<br />

vafis fafium emuit, ca cl* qu;u, pro diametro vent, cum velocitare<br />

praedi&a efiIuere d&et.<br />

In fequcntibus igitur, piano foraminis parallelurn duci inteIIiga-<br />

ILK planurn aliud fupcrius ad diltantiam diametro foraminis azqua-.<br />

lcm vel paulo majorem & foramine majorc pertufum, per quad<br />

utique vcna cadat qu:': adxquate impleat ;<br />

[<br />

foramcn infcrius E F, acque adco cujus<br />

diameter fit ad diametrum foraminis in-<br />

Be<br />

ferioris ut 2 7 ad 21 circiter. Sic enim<br />

vcna per foramen infcrius perpendicu- l< i . . ...I_....<br />

*. . .. . . ..-I,.,,,,<br />

..:<br />

Jariter tranfiibic; & quantitas aqux ef- A i.<br />

fluentis, pro magnitudine foraminis hujus,<br />

ea crit quam i’olutioProblcmatis poilulat<br />

quamproxime, Spatium vero quad<br />

planis duobus & vena cadelIte clauditur,<br />

pro fundo vafis haberi potek Sed ut<br />

Colutio Problcmatis fimplicidr fit Sr magis<br />

Matl~emntica, pwfiat adhibere planum<br />

folum inferius pro flmdo vafis, Sr C scil? l!J<br />

fingerc quad aqua qua per glaciem ceu per infundibulum dcflucbat><br />

& 2 vafc per foramcn 238’ egrediebatur, motum Chum perpetuo<br />

f&vet 8~ glacies quietem ham eciamfi in aquam fluidam<br />

rchlvatur4<br />

G&s, 2, Si foramcn 2Z.F non fit in medio fundi vafis, fed fundum<br />

alibi pcrforetur : aqua cflluct: eadem cum velocitatc ac prius,<br />

ii modo eadem fit foraminis magnitude. Nam grave majori quidcm<br />

tcmpare dckcndit ad ean profunditatem pcs lineam oh<br />

liquam quam per hleanr pcrpe icularcm, kd dckendendo candcm


nE hqoru den] velocitatem acquirit in utroque ca& ut G%G~~ demon-<br />

CORPORU~l*<br />

Jfravit,<br />

&J. 3, Eadem efi aqua: velocitas ef8uentiS per foramen in Iatere<br />

vatis. Narn fi foramen parvum iit, UC IIlt~~VidlU~ iI7tcX fiiperficle,~<br />

AB t;r IC’L quoad fedurn evanefcat, 8~ vena aqu;\: horizonraliter<br />

exilientis figuram Parabolicam eft‘ormet : ex latere r&o<br />

llujus ]Esarabol3: colligetur, quod velocitas aquz effluentis ea fit<br />

quam corpus ab aqua in vafe itagnantis altitu$ne Hq vel .?G cadendo<br />

acquirer% potuiffet. Fa&o utique experlfl+o lvVe;ni. quo&<br />

fi altitude aquz fiagnantis fupra foramen e*f’t vl@ntl dr,grtorum<br />

& altirudo foraminis fupra planum horizontr. p?ra~lelUm .e'rec quoque<br />

viginti digitorum, vena aqua profilientrs lncrderet In planum<br />

illud ad difiantiam digitorum 37 circiter a perpendiculo quod in<br />

planum illud a foramine demittebatur captam. Na[n fine reGfien.<br />

tia vena incidere debuiffet in planum illud a! difiantwn digitorurn<br />

p, exiaente venz Parabolicaz Iatere re&o dlgitorum 80.<br />

C;ZS. 4, Qnnetiam aqua efluens, fi furfun kratur, edem ogreditur<br />

cum velocitate. Afcendit enim aqua e$ient.is vena parva<br />

motu perpendiculari ad aqua in vafe fiagnagtls altltudinem GM.<br />

vet. 6’1, nifi ouatenus afcenfks eius ab aerk rdifientia &wantuV<br />

lum impediattk; ac proindeea e&uit cum velocitate: qua; ah &<br />

titudine illa cadendo acquirere potuifiet.<br />

Aqua2 itagnantis particula unaqUZCl%le<br />

undique premitur xqualiter, per Prop.<br />

XI x. Lib. II,. Sr prefioni cedendo zquali<br />

impetu in omnes partes fertur,, five - ^ de- SC<br />

kendat per foramen in FL&O valfisa, ii~ A<br />

horizontallter eMuat per foramen,in ejw<br />

latere, five egrediatur in canalem & inde<br />

akendat per foramen parvumin fuperiore<br />

canalis parte fa‘aaum. Et vel:ocitatem qua<br />

aqw e@uie, earn etk quam in, hat Propofiti0.w<br />

aflignaBvi.rnus,, non folum aatione<br />

colligitur,,kd~ eciam per experi,menta<br />

norifima jam defcripta manifefium efi. C<br />

GQ., 5~ Eadtem ei3 aqua eflkentis wlooitas Gve fi~wca. foraminis.<br />

fit cincularisi five q&uadr;ata, v.el; triangullarisi aut alria qukun$wz citi-,<br />

c&wi zqualis; N:am,velocitas. a&r;fe e&ientis non pan&t a, figusa<br />

forwinis kd ab eju, akitudine infra: planurn XC.&. ”


PRINCIPIA MATI-IEn/iATICA. 3c7<br />

mergatur, & altitude aquze flagnantis fiupra fundum vafis fit GA! : ~13 p n<br />

velo:itas quacum aqua qua2 in vafe efi, effluet per foramen E E’S EC us Ipw ;-<br />

in aquam fiagnantem, ea erit quam aqua cadendo & cafu fuo de-<br />

Ccribendo altitudinem .?I? acquirere potcfi. Nam pondus aquas<br />

omnis in vafe qua2 inferior efi fuperficic aqua2 itagnantis, fuItinebitur<br />

in zquilibrio per pondus aqua fiagnantis, ideoquc motum<br />

aqw defcendentis in vafe minime accelerabit. Patebit etiam PC<br />

hit Cafus per Experimenta, menfurando fcilicct tempora quibus<br />

aqua effluit.<br />

Carol. I. Wine ii aquas altitude CA producatur ad K, ut fir AR<br />

ad CK in duplicata ratione areas foraminis .in quavis fundi parce<br />

fa&i, ad aream circuli A B : velocitas aqua efhuentis squalis erit<br />

veloeitati quam aqua cadendo & cafu fuo defiribendo altitudinem<br />

KC acquirere poceft,<br />

Carol. 2. Et vis qua totus aquas exilientis motus generari potef?,<br />

Equalis efi ponderi Cylindrica columnar aqulr: cujus bails efi foramen<br />

E F, & altitudo z G.Z vel 2 CK. Nam aqua exiliens quo<br />

tempore hanc columnam squat, pondere fuo ab altitudine G I cadendo,<br />

velocitatem Guam qua exilit, acquirere potefi,<br />

Corot. 3. Pondus aqua totius in vafe ABZ) C, eO ad ponderis<br />

partem quz in deffuxum aquas impendicur, ut fiumma circulorum<br />

AB & E F, ad duplum circulum E F. Sit enim IO media proeortionalis<br />

inter IN & IG j & aqua per foramen E F egrediens,<br />

quo tempore gutta cadendo ab I’ defiribere poffet altitudinem IG,<br />

Equalis erit Cylindro cujus bails eR circulus E F& altitude efi 2 I G,<br />

id efi, Cylindro cujus baGs efi circulus AB & altitude efi t 10,<br />

nam circulus E F efi ad circulum A B in fubduplicata ratione<br />

altitudinis I H ad altitudinem IG, hoc efi, in fimplici ratione me.-<br />

diaz proportionalis IO ad altitudinem IG: & quo tempore gutta<br />

cadendo ab I defcribere ,poteft altitudinem II, aqua egrediens<br />

azqualis &it Cylindro cujus b&s efi circulus AB & alticudo efi<br />

2 ZH: & quo tempore gucca cadendo ab 1 per H ad G defcribit<br />

altitudinum differentiam H’G, aqua egrediens, id efi, aqua tota in<br />

iijido ABNFE M aqualis eric differentk Cylindrorum, id efi,<br />

Cylindro cujus b& eft AB & altitude 2 HO. Et propterea<br />

aqua tota in vak ABfDC eit ad aquam totam cadentem in<br />

lolido AB NFE M ut HG ad z HO, id efi, ut HO +OG<br />

ad 2H0, fku kW+IO~ad z IH. Sed pondus aqua: totius in<br />

Mido AB ALREM in aqua: defluxum impenditur : ac pro-<br />

Rr 2 inde


308<br />

inde pondus aqua totius in vafe efi ad ponderis partem qux id<br />

~!~~~~~vh~ defluxum aquzc impenditur, ut I H-t- IO ad 2 IH, atque adeo ut<br />

fllmula circulorum E E & AB ad duplum circulum IEI?<br />

&oZ. 4, Et hint pondus aqu3: totlus in vafe ki’B ‘D C, efi ad<br />

ponderis partem alteram quam fundum vafis rufiinet, ut filmma<br />

circulorum AB & EF, ad differentiam eorundem circulorum,<br />

CO&. 5. Et ponderis pars quam fundum vafis ihfiiner, efi ad<br />

ponderis partem alteram qua: in defluxum aqux impenditur,, ut<br />

difFerent.ia circulorum AB & EF, ad duplum circulum minorem<br />

EF, five ut area fundi ad duplum foramen.<br />

CO~U,!. 6. Ponderis autem pars qua fola fundum urgctur, eit ad<br />

pondus aqua: totius quz fundo perpendiculariter incumbir, ut cir-<br />

CUIUS A B ad fQmmam circulorum AB 8~ E F, five ut circulus<br />

A B ad exceffim dupli circuli AB iupra fundum. Nam ponder&<br />

pars qua fola fundum urgetur, efi ad pondus aqua totius in vafe,<br />

ut differentia circulorum AB & E F, ad iin-nmam eorundem circulorum,<br />

per Cor.4 ; & pondus aqua: totius in vafe efi ad pondus<br />

aqua totius qua: fundo perpendiculariter incumbit, ut circulus<br />

AB ad differentiam circulorum A B & E 3’. lraque ex zquo<br />

perturbate, ponderis pars qua fola fundum urgetul; efi ad pondus<br />

aqua totius quaz fundo perpendiculariter incumbit, ut circulus<br />

A B ad firmmam circulorum A ,B 6r E E vel excefllm dupli circuli<br />

AB fupra fundum.<br />

Cmd. g. Si in medio foraminis E 8’~ ~““.““““” .‘.,.1,..,.,...,...<br />

1,ocetur Circellus TL$ centro G defiri- . i I’<br />

ptus’ & horizonti @alJelus: pondus *<br />

aqu;e quam circellus ille ii&et, majus<br />

efi ponde’re rertizc partis Cylindri a-<br />

quae cujus bails efi circellus ille & altitudo<br />

efi G H. Sit enim A BNFE M,<br />

carara&a vel columna aquas cadentis<br />

axemhabens GH ut fipra, 8s congelari.<br />

inteIligatur aqua omnis in vafe, tam<br />

in circuitu catara&a quam fiipra circell~un,cujus<br />

fluiditas ad promptifflm’um<br />

,T . . .- - s3EP<br />

rx celerrlmum aquas dekenfim non requiritnr.<br />

Et. fit. T .i’Z.$ij col’umna,aquaz<br />

fupra circelluni congelaca, verticem: habens H. & alti-:<br />

cudinem< G Ho. Et q,uemadmodum aqua ,in circuitu ,catara&a conelata<br />

AIMEC, B.iVFtD convexa efi in fqperficle ,interna k?ME~A<br />

5 d\dP verfus ca~kb5kai-n. kadenkm, firC etiam hgc, c&m&~HJ&<br />

COM-


PRINCIPIA MATHEMATICA. 303<br />

COllVeXa Wit verfus catara&am, Es propterea major Cone cujus ba-<br />

GS eit circellus ille F’$& altitude GH, id efi, major ter& parte ~~.~~.“:i::‘~~.<br />

Cylindri cadem bare & altirudinc dekripci, Suflillet autem circehs<br />

ik pondus hujus columnar, id elt, pondus quad pondere<br />

Coni ku tertiz partis Cylindri illius majus efi.<br />

a5bral. 8. Pondus aqua quam circellus vatde parvus CQJ $[ufiinet,<br />

akor efi pondere duarum tertiarum partium Cylindri aqux cujus<br />

bails CR circellk ille & nltittido eit MG. Nam fiantibus jam pofitis,<br />

dekribi intelligacur dimidium Sphzroidis cuj,s bafis ef2 cir-<br />

CYRUS ilk & feemiaxts five altitude efi HG. Et hx:c figura ,uqualis<br />

erit duabus tertiis partibus Cylindri illius 8.z Comprel~eI~der coluln-<br />

Ilam aquaz congelata:,‘PHR cujus pondus circellus ille Cclfiinet.<br />

Mam ut motels aqulr fit maxime dire&us, coIumm~ illius fuperficies<br />

extcrna concurrct cum baG ‘P g in angulo nonnihil acute,<br />

propterea quod aqua cadendo perpetuo acceleratur & propter accelerationem<br />

fir tenuiorj 8r cum angulus ille iit reQo minqr, hrec<br />

cdunma ad inferiores ,ejus pa’rte,s jacebit intra dimidium.Spharoid<br />

c$is,: I$A&,n yero,tur@m’acuta Fr$t f@- cafpidata, ne’ h&iiont;ilis<br />

r$ot.qs ,yqu~,,ad qerticem $p,hzrqld{F fit mfi+c velocior quam ejus<br />

~~)$k:~&2Qiit~r& v&i”us, “Et ‘iJOb“ik;iil’os’ eft &rcellus P ,&eo<br />

a&t’i6r erit vertex colum~~‘~; & cir~ellb in $finitum: diminuto, angy.hs<br />

fp -K& in infink&. diminuetur, & propterea, cdlumna jac&it<br />

intra dimidium Sphxroidis. Eit ig$uf, cqlumna, Jla kinor<br />

dimidio Sphzroidis, f&u duabus tertiis partrhus CyIindri cujus bafis.<br />

& .&elf us i$ 82 .altit,u&T~G, k& Su,fiingt ap t,em ,citcellus &rn .aqu32<br />

$&d&i I~tijus. cdlk&nz kquz$m , ~~~.,Tpo~&+aqua3. amt)ientis in :<br />

&fIuxuz-n ejus impendatur.<br />

CO&, 3, Pondus aqua quam circellus Yalde parvus 5?2 Cufb-<br />

. proxinm<br />

~- /<br />

L.EbiM A.


+~h&, pi Jecundtim longitudinem foam unif~rmiter progredhr,<br />

.yej$&&z ex auEitu we1 diminata e&s longiatudine non mutu~;<br />

~ideope eadem e/i cum refipentiu ~irculi eadem didme~ro de-<br />

Jcripi & eade% welocitate ~ecundum liheunz re&m plana zp.<br />

@B perpendhldrem progredientis.<br />

NanI Iatera Cylindri motui ejus minime opponuntur: & Cy<br />

lindrus, longitudine ejus in infinitum diminuta 3 in Circulum<br />

wxtitur,<br />

P~OPOSITIO XXXVII. THEOREMA XXIX*,


]PR.HVCIPIA MATHEhft%TI@‘A. 311<br />

Et (per Car. IO> Prop.xxxvr) G VafiS latitude fit iilfinita>ut Ii- .L~BI:N<br />

neola ~$1 evanekac & altitudines IG, NG zquentur : vis aquz SECtJ’Tr’“<br />

defluentis in circellum erir ad pondus Cylindri cujus bails efi circellus<br />

ilk ok alcitudo efi f IG, UC E Eq ad E Fq - f P$Q quam<br />

proxime. Nam vis aqua, uniformi motu defluentis per town canalem,<br />

eadem erit in circellum ‘Pg in quacunque canalis parte<br />

locatum.<br />

Claudantur jam canalis orificia E F, ST, & akendat circellus in<br />

fluid0 ui;dique compreffo & akenfu fuo cogat aquam fuperiorcm<br />

defcendere per fpatium annulare inter circellum & latera canal&:<br />

& velocitas circelli afcendentis erit ad velocitatcm aqu”:<br />

dekendentis ut Ukrentia circulorum E F & T g ad circulum<br />

‘p 2, & velociras circelli akendentis ad iiwnmam velocitaturn,<br />

hoc efi, ad velocitatem relativam aqus dekendentts qua pra+<br />

terfluit circellum afcen’dentem, ut differentia circulorum EF &<br />

‘p& ad circultrm EF, ‘five UT E Fq -T&Q ad E Fq. Sir illa<br />

velocitas relativa Equalis velocitati qua fiipra ofienfiim eR<br />

aquam .tranfire per idem fpatium annulare dum circellus interea<br />

immotns manet, id efi, ‘velocitati quam aquia cadendo & cafii fuo<br />

&&!cribendo: altitudlnem BG acq.uirere potefi: & vis aquze in circel1u.m<br />

afcendentem eadem erit ac priusr per Legum Cor. 5= id efi,-<br />

Kefifiemtia circelli afcendentis erit ad pondus C$lindri aqua cujus,<br />

bafis. eft circellusille & a,ltirudo efi t IG, nt E Bq ad E Fg-+ ‘PQ<br />

quamproxime. ‘Velocitas ctutem circdli e+ Zd. Veloci$atem quam<br />

qua ca$endb4 & cati fu.0 &kcibetid:o’ akitudineti PG acquirits,<br />

UC‘EFq-Peq adEFg.<br />

Au.gea,tu.r a.m$i$udo cantalk Sfi infinituZi3 : QE jrationes ill& inrelr;-<br />

E Fq -P&&J & E Fq; interque E Fq Sr: E Fq - 2 T,@q accedent<br />

ultimo. ad rationw zequalitacis. Et propterea Velocicas circelli<br />

ea nunc erit quam aqua cadendo Sr cafu fuo def?ribendo al-.<br />

aitud,inem dE acquirere pot& Reffientia vtro ejus zqrralrs evam,<br />

dec ponderi Cylindri: cujus. ba& efi ,circell,as ilk &, altitude diiw;lidiUrn<br />

efi a,ltictidiSs IG,. a- qua Cylindruo cadere &bet ut velocitatem<br />

circelli akendenris acquirac;. 8t hati velocitate Cylindrus,.<br />

tempore cadendi, quadi+uplu-m longitudinis fuz dekri bet, Refi-<br />

&entia awem~Cylin&iJtiac velocitate fecundurn longitudinem fuam<br />

pr.ogtedientis, -eadem efi cum Refifientia circeldi per Lemma 1~ 5.<br />

ideoque: azqu;llis, ef% Vi qua motus;*e!jus, interea dkm quad,ru@um<br />

longitudink fuuaa defkx(ibis3 gczneran: po~A% q-uamproxime.<br />

9i


,<br />

l)E Moru si longicudo Cylindri,auge?ur ~1 minuatur : HDXXW ejus rat &<br />

~onronut~’ tempus quo quadruplum longlrudinis iiw dekribic, augebitur vel<br />

minueeur in eadcm ratione 5 adeoque Vis illa qua motus au&us vel<br />

diminukus, tempore pariter au&o vel di.minuro, generari vel tolli<br />

p&it, non mucabitur ; ac proinde etiamnum azqualis efi reGfientiz<br />

C,ylindrl ‘, nam & ha2c quoque immutata manet per Lemma<br />

IV.<br />

Si d,enfitas Cylindri augeatur vel minuatur : niotus ejus ut 81<br />

46bis qua motus eodem tempore generari vel ,tolli potefi, in eadem<br />

ratione augebirur vel minuetur, Refifkntia itaque Cylindri cu.-<br />

j,nfcunq,ue eric ad Vim qua cocws ejus IIIO~US, inrerea dum qua&uplum<br />

Iongirudinis ,fi13: dekribit , vel generari pofit vel tolli, ut<br />

denfitas Evfedii ad derifitatem Cylindri quamproxime. &E.‘D,<br />

Fluidum autem comprimi debet ut fit cohnuum, continuum<br />

vero efie,& non elafiicum W prk-ffio omnis ClUX ab ejus comprefione<br />

or$ur yropagetur in infianti &, in omnes moti corporis partes<br />

zqualiter agendo, refifienciam non mutet. Prefio utique qua: a<br />

motu corporis oritur, impenditur in motum partium fluidi generandurn<br />

& ,R+fientiam treat, Preffio autem qux oritur a cornprefione<br />

fluid!, :utcunque fortis fit, ii propagetur in initanti, null<br />

]um generat motum in partibus fluidi continui, nullam omnino inducit<br />

mows mutationem; ideoque refiitentiam net au&et net miwit,<br />

Certe A6tio fluidi, quaz ab ejus compreffionc oritur, fortior<br />

effe non”poteiE in. partes pofiicas corporis moci quam in ejus partes<br />

aB,ticas, ideoque refifientiam, in hat Propofitione defcriptam<br />

minuere non poteft : & fortior non eric in partes anticas quam in<br />

pofiicas, ii modo propagatio ejus infinite velocior fit quam motus<br />

corporis preffi, Infinite autem velocior erit & propagabitur in in:<br />

&anti, ii modo fluidum fit continuum & non elafiicum.<br />

Gwol. I. Cylindrorum, qui fecundurn longitudines has in Mediis<br />

,concinuis infinitis uniformiter progrediuntur, refifientia: f’unt in ratione<br />

qua: componitur ex duplicata ratione velocitatum Sr duplicata<br />

ratione diametrorum & ratione denfitatis Mediorum.<br />

CWQZ. 2. Si amplicudo canalis non augeatur in infinitum, Sed Cy<br />

l&dr,us ,in Media quiefcente inclufo kcundum longitudinem fuam<br />

pwgredi~+ k interea axis ejus cum axe canalis coincidat : Refifien!ia<br />

?JuS erit ad vim qua totus ejw motus, quo tempore ,qua-<br />

,druplum longitudinis fuua defcribit, vel geilerari poiIi.t vel tolli,<br />

h .ratione quaz componitur ex ratione E Fq ad E E q - $ Pgq<br />

kmel


P~INCIPIA MATHEEL4TIcA. 313<br />

fimel, &’ iatiome E Fq ad E Fq i cP&)g his, & ratione denfitatis LAM p.rc<br />

sl?ccsL~u~.<br />

Medii ad denfitatem Cylindri.<br />

Cord. 3. Iifdem pofitis, & quad bgitudo L fit ad quadruplum<br />

longitudinis Cylindri in ratione qux componicur ex racione<br />

E FCp$ Pgq ad E F 4 kmel, & ratione 15 &‘q- 12 qq ad E Fq<br />

bis: refiitentia Cylindri erit ad vim qua totus ejus motus, irxerea<br />

dum Iongitudinem L defcribit, vel tolli poflit vel generari, ut<br />

denfitas Medii ad denfitatem Cylindri.<br />

In hat Propokione refifientiam invefrigavimus quz oritwr a<br />

fob magnitudine tranrvercz febionis Cylindri, negle2k.a refiitcntix<br />

parte quz ab obliquitate motuum orirl poflit. Nam quemadmodum<br />

in cacu primo Propoficionis XXXVI, o&quitas motuum quibus<br />

partes aqua in vafe, undique convergebant in foramen E IF,<br />

impedivit effluxum aqua illius per foramen: fit in hat Propofitione,<br />

obliquitas mocuum quibus partes aqua ab anteriore Cylindri<br />

termino preK’k,cedunt prefitini & undique divergunt, retardat eon<br />

rum tranfitum per loca in circuitu termini illius antecedentis ver-<br />

Eus pofieriores partes Cylin+ ‘, eficitque ut fluidum ad majorem<br />

dlifiantiam commoveatur & refifientiam auget, idque in ea fere<br />

ratione qua effluxum aquas e vafe diminuit, id efi, in ratione dup<br />

licata z 5 ad 2 I circiter. ,Et quemadmodum, in Propqficionis illius<br />

cacu primo, efFecimus ut partes aqke yerpendiculariter & niaxima<br />

copia tranfirent per foramen E,‘F, ponendo quod aqua, omnis in<br />

vak yu32 in circuitu catara&ta congelata fuerat, & cujus motus<br />

obfiquus erat & inutilis, maneret fine motu : fit in hat Propofitione,<br />

ut obliquitas motuuti tollacur, & partes aqua motu maxime<br />

dire&o tsr; brevifimo cedentes facillimum prabeant tranfitum Cylindro,,<br />

& iola maneat refifientia qw oritur a magnitudine k&ionis<br />

tranf+erfz, quzque diminui non potefi nifi diminuendo diametrum<br />

Cylindrl ‘, concipiendum ek quod partes fluidi quarum<br />

Pnotus fiint obliqui & inutiles & refifientiam creant, quiekant inter<br />

fe ad utrumque Cylindri terwiinum,<br />

& cohazreant & Cylindro<br />

H-f-----i<br />

jungantur. Sit ABCB re&an-<br />

,gulum, & ,fint A E & g J!$ a!cus F ,,;:“......“g..‘--...- ’<br />

dub Parabolici axe AB defcnpti, _ *++lz~y,T<br />

3 J .,’<br />

hxxe autem reck cpod fit<br />

tigna


uI! Mor U tium HG,defcribendum acylindro<br />

HI---IG<br />

CORPORVM. cadentedum velocitatem ~I.Kull w-<br />

quirit, UC HG ad $AB. Sint etiam<br />

c f7 & ‘z> F arcus alii duo Para- F .,:::_::--.‘--.-.-‘-..‘e<br />

bolici, axe c’ D & latere re&O<br />

*---.a...<br />

quad fir prioris lateris re&i qua-<br />

33 113<br />

druplum dekripti j St convoiutione figure circum axem E Fgeneretur<br />

folidum cujus media pars AB 13 c fit Cylindrus de quo<br />

agirnus, & parres sxtremae AB I3 & Cz) Fcontineant partes fluldi<br />

inter fe quiekences & in corpora duo rigida concrecas, qux Cy-<br />

]indro utrinque tanquam caput & caucia adhzreant E,r folldi<br />

E ~6;‘$‘.Ll, b, fecundum longitudinem axis fui FE ia partes verfus<br />

E progredientis, refifientia ea erit quamproxime quam in hat<br />

Propofitxone dekripfimus, I ‘d efi, quz rationem illam habet ad<br />

vim qua totus Cylindri motus , interea dum longitudo SAC motu,<br />

i]io umformiter contmuato dekribatur,. vel tolli pofit vel genera.rj,<br />

qudm denfitas pi1 ui d i h a b, et ad denfitatem Cylindri quamproxime.<br />

Et hat v! Refiltentia minor ege non pot& quam in, ratio& 2 ad;s,<br />

per Coral, 7. Prop. XXHVI.<br />

‘.<br />

L E M M A V.><br />

Si: Cylindhw, ,cP$lera& Spbarois, quorum latitr&aes~fht- quales,<br />

in,. madiD canalis vlindrici ‘ita locentur fiicce&;e at eorum<br />

ages cwz age canalii coincidant : b&c corpora fEum.m.<br />

aqu jer cagalens ayualiter impedient. .<br />

Nam fpaeia inter Canalem & Cylindrum, Sphzram, & Sphawidem<br />

per qua2 aqua tranfit, Sunt. aqualia : & aqua per aqJ.lalia. fpada.<br />

zqualiter: tranfit.


Eadem c& ratio corporum omnium conwxorum &C rotundo-.<br />

rum, quorum axes cum axe canalis coincidunt. Difl-‘ercntia aliqua<br />

cx major42 vel minore fri&ionc oriri potcli ; kd in his Lemmncis<br />

corpora effe :polieifima I‘upponimus, & Medii tenacitarcm & FriQiollem<br />

effe nullam, & quad partcs fluidi, quz m&bus iuis obhquis<br />

& fupcrfluis fluxum aquz per canalem pcreurbarc, impcdire, & rctardare<br />

poffunt, quiekant intier ik tanquam gclu confir%%, & corporibus<br />

ad ipCorum paws ant&s & pofiicas adhxrcant, pcrindc<br />

UE in SchoIio Propofitionis przcedentis cxpofik Agitur cnirn in<br />

Eequenribus dc rcfikntia omnium minima quam corpora rotunda,<br />

datis maximis fc&ionibus tranfverfis defcripta, habcwpoffun t.<br />

Corpora fluidis innatantia, ubi movcntur in dire&urn, cficiunt<br />

ut fluidurn ad partem anticamak-endar, ad pofiicam i‘ubfidat, pr;x-‘-<br />

Gzrtim fi figura fint obtub; & indc rcfifientiam paulo rnajorcm<br />

fenciunt quam fi capite & cauda fint acutis. Et corpora in flllidis<br />

elafiicis mota, fi ante & pok obcufk fint, fluidurn pnulo magis<br />

condcnknt ad anticam partcm Bc paulo magis relaxant ad poiEicam 5<br />

& inde refifientiam paulo majorcm kntiunt quam fi capite & cauP<br />

da fint acutis. Scd nos in his Llemmatis & Propofitiouibus non<br />

agimus de Auidis claRicis, fed de llon &&cisj non de jnfidcntibus<br />

fluido, fed dc altc immerfis. Et ubi rcfifientia corporum in Auidis<br />

non elafiicis innotcfcit, au cnda erit haze rcfikn tia aliquau t.ulum<br />

tam in fluidis elafiicisr qua K is elt Aer, quam in Kupctficictus fluid+<br />

rum fiagnantium, qualia fint maria & palucfes.


CoRPoituD’ I)RCX?OSITIO XXXVIII. THEOREMA XTxx.<br />

&z propccrea VIS 1I1a, quze tollere pofit motum omnem Cylindri<br />

interen dum Cylindrus defcribat loqgitudinem quatuor diametrorum,<br />

Globi motum omnem rollet mterea dum Globus dei’cribat;<br />

du>,s tertias partes hujw Iongitudinis, id efi, 08~ tertk ‘parees<br />

diametri proprixz. Refiitentia autem Cylindri efi ad hanc Vim<br />

quamproxime ut deniitas Fluidi ad denfitatem Cylindri vd Globi,<br />

per PrOPa XXXV I I j & Refifientia Globi ayualis efi Refifientiz Cylindri:,<br />

per Lem.v,vI,vix. &J%.D.<br />

Coral. I. Globorum, in Mediis comprefis. infinitis, refifientiaz funt<br />

in ratione quae componitur ex duplicata racione velocitatis, & duphcata<br />

ratiorle diametri, & duplicata ratione denfitatis Mediorum,<br />

Coral, 2. Velocitas maxima quacum Globus, vi ponderis fui cornparativi,<br />

in fluid0 refifientc potet? defcendere, ea efi’quam acqu&<br />

rere pot& Globus idem, eodem pondere, abcque refifientia cadendo<br />

8~ cafu fuo dekribe?do lpatium quod iit -ad quatuor tertias<br />

partes diametri fue ut denfitas Globi ad denfitatem Fluidi. Nam<br />

Globus tempore cafus f’ui, cum vclocitate cadendo acquifita, defcribet<br />

fpatium quad erir ad OQO tertias; diametri fuzz:, ut denfitas<br />

Globi ad denfitatem Fluidi 5 Sr vis ponderis motum hunt generang,<br />

erit ad vim quz motum eundem generare poflit s[uo temptire Gl&-<br />

bus oQo tertias diametri fuua: eadem velocitate defcribit, ut &nfitas<br />

Fluidi ad denfitatem Globi : ideoque per hanc ‘Propofitionem, vis<br />

ponderis aqualis erit vi Refifientlaz, & propterea Globum accele.,<br />

me non potett.<br />

Carob. 3. Data 8r den&ate Globi & veJo&$e ej,s fib: initia<br />

Motus, ut Sr denfitate fluidi cbmpref?i quie&ntis in qua Globus<br />

movetw datur ad omne rempus or: vclocitas Globi &I ejus refi.-<br />

a&a & f@bum ah eo detiriptum, per Co,roL 7a prop. xxxv.


~~)RUW~IVA MATHEhkATICA. 31~<br />

Carol. 4. Globus iu fluid0 comprefl’b quicl’ccntc e,jufdem fecum LIIJER<br />

d~nfitatis movclldo ) dimidiam motus iiri partern prius amittet SE~IJI+~U~~<br />

quam longitudincm duarum ipfius diametrorum dekripfkrit, per<br />

idem CoroI. 7.<br />

PROI’O’S~TIO XLJ :P,RqBLEMA IX.<br />

sit A pondus Globi in vacua, B’ pm&s ejus in Media refk<br />

fienre, D diameter Globi, Fd fpatium quo! fit ad $ D ut denfitas.;<br />

‘@Tobi ad denfiratem Medii, id efk, ur A ad A -B, G tknpus quo+<br />

Globus ondere .B a&que: refi,fientia ,,cadendo dekribit fpatium Fg.<br />

& H ve P ocitas quam ‘Glc$us *~IOCCC caCi fuo acquirit. Et eric I-1<br />

velocitas maxima quacum. Globus, pondere fuo B, in ,Medio refifiente<br />

poreIt defkendere,. pek f$oro!. 2> Prop. xxxv I 1 x.5 & refi-.<br />

Rentia quam Globus ea cum velocitate defcendens patitur, aqua-<br />

Es. wit ejus ponderi B : refiitentia vero quam patitur in alia quacunque<br />

velocitate , erit ad pondus B in duplicata racione velo-<br />

‘tatis hujus ad velocitatem- illam maximam G.,$ per: oral, Is,<br />

op. XXXVILI. ,;<br />

i ,,


. . .<br />

2 P’<br />

J<br />

gc efi refioentia quz oritur ab inertia mater& Fluidi.<br />

DE MOTU Ea<br />

.CDRPORUM vero qu3: oritur ab elafiicitate, tenacitate, s6 fri&ione par;tium<br />

ejus, iic invefiigabitur.<br />

Demjrtatur Globus ut pondere fU0 B ,in Flui& defcendat;<br />

k fit p rempus cadendi, idque in miuut1.s iecundis fi ternpus<br />

G in .minucis -fecundis habeatur. Invenlatur numerus abfo-<br />

lwus N qui congruit fitque L,<br />

]Log&hmus numeri NT g . & ,veIocitas cadcndo acquifita crit<br />

-<br />

w- I ZPF<br />

NTI H[ ~ alcitudo autem defcripta erit -c- .X,386294~6r t I? +<br />

+,60~170186LF. Si Fluidum kc: srgfundum fit, negli.gi pot&<br />

terminus 4jbOsI7OI86L F; & erit -G--+- X,38629+361.1 p altitudo<br />

&fcripta quamproxime. Patem hzc per Eibri fecundi Prdpo-<br />

Grionem nonam & ejus Corollaria, czx Hypothefi quad Glo.<br />

bus nullam aliam patiatur refifientiam nifi qux oritur ab inertia<br />

materi Si verb aliam infuper refifientiam patiatur, d&enfus<br />

erit tardier, & ex retardatione innotefcet quantitas hujus re-<br />

43len tiaz.<br />

Ut corporis in Fluid0 cadentis velocitas & defcenfus facilius ina<br />

notefcant compo’lii Tabulam fequentem, cujus columna prima<br />

denotat tempora defcenfus, kcunda exhibet velocitates cadendo<br />

acquifitas exifien te velocita te maxima I oooooooo~ tertia exhibet<br />

f’atia temporibus illis cadendo defcripta, exifiente 2 F fpatio quod<br />

corpus tempore G cum velocitate maxima dekribit, & quarta ex-<br />

Iribet fpatia iifdem terporibus cumz ;Iocitate maxima defcripta,<br />

Humeri in quarta cohmna Tunt p & fubducendo numerum<br />

g,3862944 -4,do~1702 L(, inveniuntur numeri in tertia cohmna, &<br />

multiplicandi lint hi numeri per Cpatium F ut habeantur lrpatia<br />

cadendo dekripta. Qu,inta his i&per adje&a efi columna, qua<br />

qcontinet fpatia defcripta iifdem tempo&us a corpore, vi ponder&<br />

Ski ,wnparativivi BJ in vacua cadcnte.<br />


Tempuru<br />

P<br />

Spat&z caden-<br />

~$6 defir+ta<br />

in ,fltLidL?<br />

Spatia mutt7<br />

muximo de-<br />

Jcripta.<br />

o,oor G<br />

o,oi @<br />

O,I G<br />

0,2 G<br />

033 G<br />

&4 G<br />

035 G<br />

0,6C<br />

097 G<br />

0,8 G<br />

O,P G<br />

IG<br />

ZG<br />

3G<br />

;G”<br />

66<br />

7G<br />

8G<br />

9G<br />

1OG<br />

99993%<br />

399 967<br />

9966799<br />

vJ737r32<br />

2913I261<br />

3799489(-j<br />

46211716<br />

f3704PY7<br />

6~36778<br />

6G403;677<br />

7x629787<br />

Vww6<br />

9Qov@<br />

995OF47f<br />

77932930<br />

99390920 1<br />

7999w7 I<br />

99999834<br />

99999980<br />

99999997<br />

99399993~<br />

o,ooooo I F<br />

O,OOOI F<br />

wo99834 F<br />

0,039736f F<br />

0~088G81 j F<br />

O,I5 59070F<br />

0,240~ 290 F<br />

0,3~02706 F<br />

~4 54 ~405 F<br />

0,58~5071 F<br />

037 196609 F<br />

~86~ 5617 F<br />

2,6jooo5 I F<br />

4,6186570&<br />

6,6143 765 F<br />

8,613 7~64 F’<br />

o,6wvgF<br />

226137073 F<br />

4,6137WPF<br />

G,6r37Q57F<br />

8,6137056F<br />

0,002 F<br />

0,02 F<br />

OJ’?I?<br />

~4 F<br />

o,ci F<br />

0,~: F<br />

T,OF<br />

WF<br />

1,4F<br />

I&F<br />

I,8F<br />

2F<br />

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6F<br />

8F<br />

IUF<br />

12P<br />

t4F<br />

16F<br />

t8F<br />

co F<br />

0,00000E If:<br />

0,ooor i;<br />

O,OI F<br />

w4 F<br />

cl,09 It7<br />

0,IbF<br />

0,25.F<br />

O,~G F<br />

0549 Its<br />

0,64 F<br />

O,&L F<br />

IF<br />

4F<br />

9F<br />

IGF<br />

2f.F<br />

36;F7<br />

49E<br />

6@<br />

3,r F-<br />

too E<br />

TJt refifientias-Fluidorum invefiigarem per Exper+nenra, paravi.,<br />

aas ligneum q.uadratum, lon@tudine &- latitudine interna d&o.=<br />

rum novem pedis LolzdinelzJs, profunditate pedum novem cum,<br />

&miife, idemque imyles4 aqua pluviali; Sr globis. ex cera & plum-.<br />

bo inclufo forma& notavi sempora defcenfus globorum, exifiente<br />

defcenfis altitudine 11~. d@torum .. p&s., Pes hlidus cut>lcus;..<br />

Jh&.ze~$‘s continet 76 libras.Roman+ ac@~ pluviahs, & pedrs hu.+<br />

,jgs digitus iblidus continet $2 un$as librze hujus”feu gra&, 2.~39 ;,<br />

ae g~~bus. aqyeus..diametp : diga wius * dehiptxxj, concinec ,gya.<br />

qw%Z


320<br />

‘pI-l[l[EcIxxx?HI& NA.‘TURAk%S<br />

DE h43ru 132,645 in Media aeris, vel grana 132,8 in Vacu?; 6~ globus qui-<br />

ConPow”a* jibet alius eft Ut excerus ponderis ejus in vxuo iupra pondus ejus<br />

in aqua.<br />

~~~~~~~ I. Globus, cujus pondus crat I 56% granorum in acre 8~<br />

77 grallorulll ill aqua, alticudinem totam dlglrorum I 12 tempore<br />

minucorum quatuor kcundorum dekripfit. Et experiment0 repetito$<br />

globus itcrum cecidit eodem rempore minutorum quatuor k-<br />

cundorum.<br />

Pondusglobi in vacua eA 156%grdl~, & excefius hujus .pondeT<br />

ris rljpr:! pondus globi in aqua efi 79f$graa. Unde prodIt* glob1<br />

diameter ~1~84224 partium digiti. Efi aURn Ut eXCeffUS lk ad<br />

pondus globi in VXLIO, ita denfitas aqua ad denfitatem globi,<br />

8; ita parces o&o tertiaz diamecri. globi (viz. 2~24197 dig.> ad.@a:<br />

tium 2 F, qudd proinde erit 4,4256 dig. Globus tempore mxnlltl<br />

unius fecundi, toto ho pondere granorum 156f$, cadendo in vacue<br />

defcribet digitos 133: ; & pondere granorum 77, eodem tem-<br />

,pore, abfque refiitentia cadendo in aqua dekribet digitos 95,219;<br />

& tempore G, quod fit ad minurum unum fecundurn in fubduplicara<br />

ratione fpatii Fku 2,2128 dig. ad 95,219 dig, dekribet 2,2128 dig.<br />

82 velocitarem maximam H acquiret quacum potefi in aqua dekendere.<br />

Efi igitur tempus G O”,I 5244, Et hoc tempore c,<br />

.cum velocirate illa maxima H, globus defcribet fpatium z F digitorum<br />

4,42$6 j ideoque tempore minutorum quatuor fecundo-<br />

.rum defcribet rpatium digitorum x I&I 245. Subducatur fpatium<br />

1~3862944 F ku 3,0676 d.&. & manebit fpatium x13,ordp digito-<br />

Turn quod globus cadendo in aqua, in vale ampliflimo, tempore<br />

minutorum quatuor fecundorum defcribet. Hoc Cpatium, ob an-<br />

,gufiiam vafis lignei pradifii, minui debet in ratione qua: componitur<br />

ex fubduplicara ratione orificii vafis ad exceffum orificii hw<br />

jus fupra femicirculum maximum globi & ex fimplici ratione ori-<br />

&ii ejufdem ad exceffum ejus fipra circulum maximum. globi, id<br />

.efi, ‘in ratione I ad o,ppr4- C&o fa&o, habebitur fpatium ‘E 1z,o8<br />

.digitorum, quod Globus cadendo in aqua in hoc vak ligneo,,tempore<br />

miriatorum quatuor kcundorum per Theoriam defcrlbere<br />

debuit quamproxime. Defcripfit vero digitos I 12 per Experi-<br />

:,.,‘.>ia‘,<br />

..mentum. ‘.<br />

Exferi’%, ‘Tfek Glrjbi’%~uAes, quorum pondera feorfim erant<br />

‘76$ gtyanorum in aere & 5$ granorum in aqua, iilcceffive demitteb%niuti?‘&<br />

untifqliii?que cecidit in aqua tempore minutorum kcund~rum<br />

qtiindecima cafi fio’kkfckibens altitudinem digitorum I 12,<br />

OryBy


omlkcum inetlndo prddeunc pondus globi in vacub ?(;,-I;gwrc~. 1, I II B Il<br />

exceffis hujus ponderis fipra pondus in’ aqua 714: gran, diameter SEC~NII(‘~~<br />

globi 0,8 1296 d&-, ot30 rercia: partes hujus diamerri 2,x67&1 a’&-$<br />

fpaciutn 2 Hi 2,s~ 17 dzi, fpatium quad globus ponderc r& gran,<br />

rempore 1’: abfque refifkntia cadendo dekribac ~2,303 dg, &:.<br />

rempus G o",p10~~* Globw igitur, vclocitace maxima quawrra<br />

pot& in aqua vi ponderis 5f;g~nz~ defccndere, tcmptlre o”,?~ 1 o 76,<br />

defiribec Cpatium 2,221 7 dig. 15( tcrnpore I $’ @atium I I 5,678 d


322 l?HILOSOPHIX NATURALIS<br />

frigus rcdrrcitur. Antequam caderent, immergebantw penitus in<br />

aquam ; ne pondere partis alicujus ex aqua extantis defcenfus eorum<br />

f\lb initio acceleraretur. Et ubi penitus immerfi quiefcebant,<br />

demittebantur quam cautiilime, ne impuKum sliquem a manu demittente<br />

acciperent. Ceciderunt autem fuccefive temporibus<br />

oi~illationum 47f, 48$, 50 & 51, dekribentes altitudinem pedum<br />

quindecim & diglrorur?l duorutn. Sed tempck jam paulo frigidior<br />

erat quam cum globi ponderabantur, ideoque iteravi experimentum<br />

alio die, & globi ceciderunt temporibus oklilationum<br />

4.9, 49f, 50 & 53, ac tertio temporibus ofcillationum 4,918, 503 gr<br />

& 53. EC experiment0 fzpius capto, Glob1 ceciderunt maxima<br />

ex partc temporibus ofcillationum 4.~$ & 50. Ubi tardius cecideres<br />

fufpicor cofdem recardatos fuiflk impingendo in latera<br />

VdfiS.<br />

Jam computum per Theoriam ineundo, prodcunt pondus globi<br />

in vacua 139-F granorum. Exce,ifirs. hujus yollderis fupra. pondus<br />

globi in aqua J 32$f glaT2. Diameter globi o,p9868 djg. O&o tertix<br />

partes diametri 2,6631$ u’@. Spatium 2 F 2,8066 dig. Spatium<br />

quod globus pondere 7; granorum, temporc minuti unius fkcundi<br />

abfquc refiitentia cadendo defcribit 9,88164 A&. Et rempus<br />

G d/,376843. Globus igitur, velocitate maxima quacum poteIt in<br />

aqua vi ponderis 7: granorum dekendere, tetnpore 0”,3@43 defkribit<br />

fpatium ~,a066 digitorum, & tempore f fjjatium 7,++766 digitorum,<br />

& tempore 2 5” feu okillationum 50 fpatium J 86,Ip r 5 I&&.<br />

Stibducatur fpatium 1,386~94 F, fku 1,9+54 ~$2. & mane&r fpariurn<br />

~8.+,2461 dig,. quod globus eodem tempore in vafk latifimo<br />

dekribet. Qb angufiiam vafis no&-i, minuatur hoc fpatiurnin ratione<br />

q,u3: componitur ex fibdaplicata ratione orificii vaiis ad<br />

exceffqm hujus or&ii fipra femicirculum maximum globi,. Lk GmpIici<br />

ratione ejufdcm orificii ad exceirum ejus iupra .circulum maximuti<br />

glObi j & habebitur fpatium 181,86 digitorum, quad glow<br />

bus in hoc vak tempore ofcillationum 50 defcribece debui~t pel:<br />

Theoriam quamproxime. -Defcripfic vero . fpatium I 82 j digitorum<br />

ternpore o[cilcillationum 49% vel To per Experimenturn;.. .<br />

.Ex~er~~ 5.’ Globi quatuor pondere I ~&gralz. in aere & 2~Qw2,<br />

$1 Bqua., kpe derni$j‘ cadebant ternpore ofcillationum 282, 29,<br />

29+ st 30, & htinnanquam: 31, 32 & 33, ‘dekribentes altitudinem<br />

pedqm:quindecim & digitorum duorum. .<br />

*<br />

Per Theorlam caq’erea debuerunt~ ‘tempord of&lktionum .igi<br />

quamproxime.<br />

Exper .


Bx/m-. 6, GlObi quinque pondere 2 X2$ g&2. in acre Csc 79: i” tr6 p. rt.<br />

aqua, fkrzpe clemifli, cadebant tcnlpore ofcil]atio~~~l,m 1f3 ,I!:, 16,~~~"~~~~~~<br />

17 & 18, defcrihnws altitudiilwl p edurn quindecltn 8~ dlgltorum<br />

d Uorum.<br />

Per ‘I?hec?riarn eadere det~~erur~t tcrilpore okillatio!lum I f<br />

~Uamproxinze.<br />

o”xper. 7. Globi quatuor porldere Z:j3$ gran. in,aere Jk 35&ghuz.<br />

in aqua, fipe demifli, cadebant rempore ofcillatlorlum 2$, 36,<br />

302, 31, 3 2 & 33, defiribentes alrit%dinem pcdum quindecim &<br />

,digiti unius cum femSe.<br />

Per Thcoriam cadere debuerrxnt tempore ofcillationum ,z8<br />

quamproxime.<br />

Caufam invefiigando cur globoruti, ejufdem ponfef-is tk magnitudinis,<br />

aliqui citius alii tardius caderenr, in hanc incldl 5 quad globi,<br />

ubi primurn demictebantur .& eadere incipiebant, ofcillarenc circUm<br />

centra, Iatere Uo quad forte gravius effet, primurn defceadente,,<br />

8~ moturn ofcillatorium gelxerante. Nam p,er o_fcillat@es<br />

Gas, globtis tiajoretn motuni communicat aqutr, qjuam il fine o&Alationibus<br />

defqendcret j & communicando, amitcic partem mow<br />

pgoprii quo defixndere de&ret: & pro majore vcl miriore oki!-<br />

latione, magis vel minus retardatur. QL&h-iaFfi globs recedlt<br />

femper a latere fuo quod per ofcillationem defchdlt, & receden-<br />

CICS appropinquat lateribus vafis’ & _ in latera- ~JOII~~U~~~KUII Impingitur.<br />

.Ec .hax ofiillatio in glob’ig @Aviorib’ws fkti.or efi, &C in<br />

majoribus a‘quam tiagis agit;it. ‘Q&a+optef, ut ofcillatio globorum<br />

minor redderetnr, globes novas ex c&a & phtibo confhxij<br />

infigendo pltlmbum in latus aliquod @cjWprope Cuij@i~%m ejtis 5<br />

2% globum ita demifi, ut latus gravvi-us, quoad fi+i potuit, effet infimum-ab<br />

initio defcenfus. Sic ofcillationeti fzi&k ftinr niulto niinores<br />

quam prius, & globi tempdhljus minus. in&qualibus cecide-+<br />

runt, us in experimentis fequentibus.<br />

Bxper. 8. Globi quatuor pond’&% gkanortiti: T 39.S aere SE Gf in<br />

z-qua, fz@e demifi, ceciderunt temfitiribuk ofti~lla’tiorhm non phrkumz<br />

quam 52, non. pauclorum quani- 509 Qs mtiAinia ex parrc<br />

tempore ofcillationum 5 1’ &kiter:, defcribtntes’ alticudinem digL<br />

torum 182.<br />

Per Thebriati cadere debuekunt’ tem@rt -ofcillationum fz<br />

drci ter.<br />

-EX~er. pb ~&lol5i -quhttibr pbndCre fyzinoliuln 273$ 'in a&C, &<br />

a&2$ lfi. siqUbi3j 'f$Gx3; d'&fiiEi ceck%fuht temporhs &illati&um<br />

1c 2<br />

IlOll


, .<br />

j-)E ivlwru 11011 pauciorum quam 12, non plurium quam 13) defcribentes ats<br />

cop LB o II u M t$udin,em cligitorum 182.<br />

per, Theorianl vero hi globi cadere debuerunt tempore orcilIa.<br />

tionuln I 1; quamproxinlc*<br />

Expeu: 10. Globi quatuor pondere granorum 384 in acre &<br />

1.19: iI1 aqua, jkpe demifli, cadebanc temporibus &illationum<br />

I7i, I&, I8< & 19, defcribentqs altitudinem digitorum I 8 1;; EC<br />

ubi cccidcrunt tempore ofcillatlonum 19, 1lOnnUnqUam au&vi im.‘<br />

pulfum corum in latera vafis antequam ad fwdum pervenerunt,.<br />

’ Per Theoriam vero cadcre debuerunt tenlpore okilJationu~~I<br />

1.5; quamproxime..<br />

Exper. II. Globi tres zqual’cs, pondere granorum 48 in acre<br />

h 3f;l in aqua, &pe demiir, cfciderune temporibus okillationum<br />

,+3+, 4.4? 442, 45 & 46 &- maxlma ex parte 4+> 8~ 45,. dekribentes.<br />

;dltitudincm digitorum I 82; quamproxlme.<br />

Per Theoriam cadcre, de.buerunt tempore okillationum 46$\,<br />

circi ter,<br />

Eipev. 12, Globi tres zquales, pond&e .granorum ~4.r in, acre<br />

e 4$, in ‘aqua, aliquoties demifi, ceciderunt:remporiGw ofcillatioy<br />

num 61~.,62,, 63,64 & ,65, defcribentes altitudinem digitorum 18%~<br />

Et. per Theoriam cadere.: ~eherwt tempare oCcilla,tionum<br />

64; quamproxime.<br />

Per hxc Experiaz?enta:manjf~ltum eR quad, ubi-g’fbbi karde ce&<br />

dcrbnt, UC. in.. experimentis fecund& quartis, quin tis, o&w&, utir<br />

decimis-. ac” duodecimis , .tcmpora cadendi re&k exhibenttir per<br />

Theoriam: at, ubi globi velocius- cecidecunt, ut, in expe.rimentis<br />

‘Textis, nonis. ac, decimis, re&fiesGa p,aul,o major extitic ,quam in<br />

,&plica~a..r@oue ylocit+is.. Nam g1,ob.i iqter cadandum ioCcilJant<br />

al,iquantglum $1 & hzc. ofciljat,io in g!,obis levioribus 6~: tardius, ca*<br />

den&bus,, ob motus., languorem cite ceffat;. in ,gravioribus autem &<br />

majoribus, ob mows fortitudinem diuti,us,durat, & non nifi p&<br />

plures :ofcilJationes ab aqua am biente cohibSeri pot& ,Qinetiam<br />

globi, quo velociores. funt, eo m,inus premuntur a fl:uido ,a4 :pop<br />

i)icas fqas, paws,.; & fi veJocitas.perpetuo augeatur, C atiwm vacuu,m<br />

tandem a tergo.r$inquent, ,nifi compreiEo flui d” i fimul au?<br />

geatur; Debet autem cbmprefio fluidi (per Prop. xxxx 4 & ,XXXIII[)<br />

augeri. .i~,. duplicata racione velocitatis, ur ,refiikntia,fic ,in eadem<br />

duplidka’ ratione. Qoniam hoc non fit, lobi velocioxw pauto<br />

minus(..premuntur,a tergo, & dcfe+ pr.c ri; ionis ,~L$us, r,&kneia<br />

*<br />

eoah .6t ‘p~do m;ljjx Lbflap, a?; &q#wn<br />

*<br />

,r;ldons: vc$aci,tatis,<br />

: &a~


C~erum. tempera obfervata.. corrigi debent. IISLUI~ globi mcr-<br />

(curiales (per Tlieoriam Gal&i) minutis quatuor ficuulldis dekribcrlc. :’<br />

pecks L~ndi~~nft.~ 2 $7 , & pedes 220 nlinutis tantunl. 3” 42”. %ahula<br />

.lignea utique, detratio peffulo, tardius devoIvczbatur quam par.<br />

erat,. & tarda fua devoluticGw impedlebat defcenfilm globorum<br />

Cub initio. T?Jam glo.bi incumbebant Tabula: prope medium .$sl, .<br />

& .paulo .qu.Ldem pcopiores erant-axi ejus quam. pefTii10. Et .liinc<br />

gempora cadendi prorogata fuerunt minutis tertiis o&odecim cir-.<br />

titer, SP jam corrigi debent detrahendo illa minu.ta, prxfkrtim iI1 :<br />

globis maj.oribus qul, Tabular devolventi paula diutius incumbe<<br />

banr propter: magnitudinem. diametrorum. C&O fa&o,, tc;npora<br />

quibUs globi Gx majores cecidere, evadens ~8’: ~.a’!‘, J” 4~~:‘~ 7”4$J’S ,,~<br />

f 57y> $yd T id?, .& 71/ +a!!.<br />

QJbjd -


326 PH~JX=ISCHX-II& NATURALus<br />

I.) c ;r lo T u (-&-,borunl igirur aere plenorum quintus, diametro digitorum<br />

C 0 n 110 !: u bl quinque pondere granorum Lb83 confiruQus, cecidit tempore<br />

8” IZ”‘, deccribendo alritudinem pedum 220. Fondus aqux huic<br />

globe xqualis, eit I 6600 granorum j Lk pondus aeris eider aqualis<br />

efi L$$PgrafZb f&l 191% grnlz j ideoque pondus globi in vacua e6<br />

502 i5 gran j & hoc pondus eft ad pondus aeris glob0 zqualis, ut<br />

qoz15 ad lph, & ita i‘unt 2 F ad o&o eertias partes diamerri globi,<br />

id efi, ad 13f digitos. Unde 2 F prodeunt z 8ped. 1 I dig. 610..<br />

bus cadendo in vacua, toto ho pondere 5021% grarlorum, ternpore<br />

minuti unius kcundi defcribit digitos 1p3f ut Cupra, & pondere<br />

483 grala. defcribit digitos 185,pog, & eodem pondere 483 gran.<br />

etiam in vacua defcribit fpatium F feeu 14ped’. 5; &k* tempbre<br />

57”’ 58’,“, & velocitatem maximam acquirit quacum pofit in aere<br />

defcendere. Hat velocirate globus, tempore 8” 12”‘, defcribet fpa-<br />

Cum pedum 245 & digitorum 5:, Aufer 1~3863 F feu 20 ped,<br />

o; dig. & manebunt z2yped. 5 dig. Hoc’ fpatium igitur glob+<br />

tempore 8’! r z”‘, cadendo dekibere debuit per Tkeoriam. Dekripfit<br />

vero fpatium 220 pedum per Experimentum. Differ&a<br />

infen fi bilis efi.<br />

Similibus computis ad reliquos etiam giobos acre plenos appli..<br />

catis, confeci Tabulam fequentem.<br />

Globorum<br />

ponderd<br />

Dia..<br />

naetri<br />

I<br />

Tem~ora cudidi<br />

ab dl- Spdtia defcribentitudine<br />

pe- d&per Tiieoriam~<br />

Exceffus<br />

jauw 220.<br />

5 Iogrim 3. 8” I 2”’ 226 pea. f 1 dic$. 6ped. I r a?$.<br />

642 532 7 42 230 9. 10 9<br />

599 5>1 7 42 227 IO : 10<br />

515 5<br />

224<br />

5<br />

483 64I, 15225 1 7 z 42 fZ ,230 225 ,’ ; I’0 5 ,. s<br />

-<br />

Globorum igitur tam in Aerc quam in Aqua. motorurn refid’<br />

fientia prope omnis per Theoriam nofiram. re&e exhibetw, tic<br />

denfitati Auidqrum, paribus globorum, velocitatibus ac magnitudii<br />

IGbas, proport$onalis<br />

efk<br />

:<br />

In


P,R,!ZCIPl[A MA.~HEMA~rca.. 3.q<br />

112 S&&o quod %z&ioni fextz fubjunfium efE, oflendimw per Lrsrn<br />

experirne:nta penduIorum quad globorum n-lqualium & zquivelo- SECuNQUS~<br />

k-tm in Acre, Aqua, & Argento viva nlotorum refifientiz:’ funt ut<br />

fluidorruw denfirates. ldem hit oltendimus magis accurate per<br />

experime:n.ta corporum cadentium in Aere Sr Aq~m. biarn pendula<br />

fingulis csfcdhtionibus motum cient in fluid0 motui pen&Ii re-<br />

&uncG Gmper contrarium, & refifientia ab hoc motu oriunda, uc<br />

2%~ refifiexltin fili quo pendulum fuf’endebatur, totam Pcnduli refifientialm<br />

majorcm reddiderunt quam refifiencia quz per cxperirllenta<br />

corporum cadentimn prodiit. Etenitn per experimenra<br />

pclddorurn in Scliolio ill0 expofita , globus ejufdem denfitatis<br />

d=um AL~UZL, dekribendo longitudincm fkmidiametri CUX in Aereg<br />

amitrere deberet mows fui parrem &. At per Theoriam in hat<br />

Optima SeBione expofitam EC experimencis cadentium confirrna-<br />

~atn, globus idem defcribend:o longitudinem tandem, amictere debcrct<br />

n2~otus fili partem tantum +&, p&to quad denfitas Aqw fit<br />

ad denfitacem Aeris ut 860 ad 1. RcGfientix igitur per experiancnta<br />

pendulorum majores prodicre (ob cauhs jam dekriptas)<br />

qwarn per experimenta globorum cadcotium, idque in rariom 4 ad<br />

s- circirer, Attamen cum pendulorum in Acre, Aqua> & Argcnta<br />

viva 0Giliantium refi~entize a caufis fimilibus Gmiliter augenntur,<br />

proportio r-efifientiarum in his Mediis, tam per experimenta pendulorunl,<br />

quay per experimenta corporum cadentium, fitis reAc<br />

~,&ibebitur. Et inde concludi potefi quad corporun,li in fluidis.<br />

~~ibufcunque fluiditlimis motorum refifientiz, cxterls paribus,<br />

gi>nt ut dknfitatris fluidorum.<br />

His. ira fiabilitzis, dicerc jam licet quamnam mQtu.9 fui partem,<br />

@obus, quilibet, in fluid0 quocunque projet%tYs, &ata ternpore amitlet<br />

quamproxime. Sic D diameter globi, 8~ V vekitas cjus fi~b<br />

$tio .L~~O~TUS~ &C T ,tempus quo globus velocitate V in vac.u.0 de.-<br />

firibec Qatium qu.od fit ad @cztium $D. UC denj.itas gIo,bi. ad. dcn&<br />

tatem Auidi: & globus in flwido illo proje&us, tempo,re quovis<br />

tV<br />

TV<br />

alio p, nmittet velocitatis fix partem -<br />

T +t’<br />

manen tc par te T-t-a’<br />

& &&&bet fpatium quod fit ad Cpatium uniformi velocitatc V eo-<br />

T+z<br />

dem rempore defiriptum in vacua, ut logarithmus numeri T-<br />

~ultiplicatus per numerum 2,3035S5~93 efi ad numerum ,$, Per<br />

Corof a


PROPOSIT1[0 XLI. THEOREM/l ,9;_‘xxH.<br />

Si jaceant particuk 12~ &, 6, d, e in linea re&t, pot& quidcm<br />

preflio dire&e propagari ab R ad e; at<br />

particula e urgebit particulas oblique poll<br />

tasf & g oblique, & particulx illxJ &g<br />

non fuflx~ebunt prefionem illatam, niG<br />

fulciantur a particulis ulcerioribus b Sr 12;<br />

quacenus autem fulciuntur, premunt particulas<br />

fulcientes; & ha: non fufiinebunt<br />

preflionem nifi fulciantur ab ulterioribus<br />

G & m eafque premant3 & fit deinceps in infinitum. Prefio igicur,<br />

quam primum propagatur ad particulas qw non in dire&urn<br />

jacent, divaricare incipiet & oblique propagabitur in infinitum 5<br />

& pofiquam incipit oblique propagari, ii inciderit in particulas<br />

ulteriores, qu3e non in dire&urn jacent, iterum divaricabit j id-<br />

‘que toties, quoties in particulas non accurate in dire&urn jacentes<br />

inciderir. SE. 2).<br />

Carol. Si preOionis, a dato pun&o per.Fluidum propagate, pars<br />

&qua obfiaculo intercipiatur j pars reliqua, quz non intercipitur,<br />

di.varicabit in fpatia pone obfiaculum. Id q.uod fit etiam demonitrari<br />

potefi. A pun&o A propagetur preflio quaquavercum,,<br />

idque ii fieri potefi Gxundum lineas reQas, & obfiaculo<br />

NBCK perforato in BC 9 intercipiatur ea omnis, .prater partern<br />

Csniformem AT $& quaz per foramen circulare B C tranfit.<br />

Planis tranfverfis dt, fg, Ilj; diitinauatur conus ATgin fruita;<br />

&z interea dum conus ABC’, pr;fi;nem propaganda, urget fru-<br />

.itum


j’jo PMPLoS~o~I?MI& NA<br />

DE MOTLJ iturn conicum ulterius degf in f<strong>Up</strong>erfiCie de, & ‘hoc fkdh.Inr<br />

6: 0 RI’ 0 I< u &I. w-get fruiturn proximum Jgih in hperficie fg, & fruiturn illud<br />

urgec frufiwm tertium, & fit deinceps- in infinitum; manifehm<br />

efi (per motus Legem tertiam) quad frufium primutn defy, re+.<br />

a&one fruiti kcundi Jg hi, tantum urgebitur & premetur in Cue<br />

perficie fg, quantum urget & premit frufium illud fecundurn,.<br />

Frufium igitur degj inter conum Ade Sr frufium fh ig corn-..<br />

primitur utrinque, & proptcrea (per Corol. 6. Prop. xix.) Fguram<br />

ham krvare nequit, nifi vi eadem comprimacur undrque,.<br />

Eodem igitur impetw quo premitur in fi~perfikiebus CA?, fg, eona;.<br />

Bitur cedere ad latera d$ 66 5 ibique (cum rigidum non, fits. fed T<br />

omnimodo Fluidurn) excurret- ac dilatabitur, nifi Fluidum ambjens<br />

adfit, quo conatus 3X-e cohibeatur. Proinde conatu excurrendi,<br />

premet, tam Fiuidum amhiens-ad latera df, eg quam fru’fium:<br />

f9 hi eodem impeN; & propterea plefllio non minus propagabixzlr<br />

a lateribus df; e in fpatia NO,. KE hint inde, quart prop<br />

pagatur a fiperfick verfus T & a,E,2>;<br />

P EL. a


~‘KOPOSITIO XLII. TWEOREMA XXXIir, SECcr’inr’r-<br />

Gas. 1, Propagetur motus a pun&o A per foramen BC, pergatque<br />

(fi fieri poteft) in fpatio conic0 SCR’P, fiecundum lineas<br />

re&as divergentes a pun&o C. Et ponamus prima quad<br />

mows iite fit undarum in fuperficie fiagnantis aqwe, Siwquc<br />

de-,,fk, h z’, k I, &G. undarum fingwlarum partes alcilrimz> vallibus<br />

tocidem intermediis ab inviqem diftin&z. Igitur quoniam<br />

aqua in undarum jugis altior efi quam in Fluidi partibus immotis<br />

LIC, NO, defluec eadem de jugorum ternhis e, g, i, G, SK.<br />

d, f, h, k, Src. hint in,de, verfus KL & NO : Sr quoniam in undarum<br />

vallibus depreffior efi quam in Fluidi partibus immotis<br />

KL, NO; ckfluet eadem de partibus illis immotis in undarum<br />

valles. D&tuxu priore undarum juga, pofteriore valles hint<br />

inde dilatantur & propagantur ver@ KL & NO. EC quoniam<br />

ritlotus undarum ab A verfis Tg fit per continuum defluxum<br />

jugorum in vafles proximos, adeoque celerior non eft<br />

quam pro celeritate defkenfus ; & defcenfus aqua, hint inde, ver-.<br />

fus KL & NT0 eadem veloeitate. peragi debet j propagabitur<br />

dilatatio unda-rum, hint inde, verfus KL & NO, eadem velocitate<br />

qua undue ipf& ab A verfus PR reQa progrediuntur.<br />

Proindeque fpatium totum hint inde, verfiis KL & NO, ab<br />

undis dilatatis rfgr, shis, t k If 3 V mfl U , kc. occupabitur.<br />

a E. 2). M~EC ita fe habere quilibet in aqua fiagnante expe<br />

riri poteft.<br />

Ctis. 2, ltionamus jam quod ‘de, fg, /j i, k I, m n defignent pdfus<br />

a pun&o A, per Medium


w<br />

Pf-lIL.O~S0BWI.A NATWRAL1[S<br />

eoquc pa&o rarius femper evadens e regionc intervallorum ac<br />

denfius e regione, pulfiium, particigabit eorundem motum,, at<br />

q~011ia1la: pulfium progrefivus ltZnotuS orltur a perpetua relaxa.<br />

tione partium denfiorum verfus antecedentia intervalla rariora,,;<br />

a pulfi~s eadem fere celeritate fijTe in Medii partes quiefiejltes<br />

A_‘L, .,X8 hint inde relaxare debent; pulls illi eadem fere celce<br />

ritate kk dilatabunt undique ira @aria immota kcb;, NO, qua<br />

propagantur dire&e a centro A’; adeoque fpatium totum x’L0~<br />

occupabunt. $E. !D Hoc experimur inSonis, qui vel monte<br />

interpofito audiuntur, vel in cubiculum per fenefiram admifi. fefk<br />

in omnes cubiculi partcs diiatant, inque angulis omnibus audiuni<br />

tur, non eam reflexi a parietibus oppohtis, quam a fen&a dire&e.<br />

propagati, quantum ex fenh judicare licct.<br />

Cm,- 3;- POnamuk+ &nicpe cpocl : morw cujufdunque genetis<br />

propagetur ab .A. per foramen- B 6: & quoniam propagatio iRa<br />

aon fit,: nifi quatenus partes,Medii centro A ‘propiores urgent<br />

commoventque partes -ulteriores j & ‘partes qw urgentur A uid$<br />

fbm, idcocpe recedunt quaquaverfim in regiones ubi n-Gnus ‘premun<br />

twr :


?IWKX’IA R%ATHEA,/i.ATI@h”i;. j 3.3, ‘<br />

mutltur: rescdcnt ezdem verbs Medii partes omnes~ quiefcclltcs, L I II 1: Ii<br />

tam laterales KL Gr NO, quam an teriorcs “6 g, eoquc pa&o s :‘cI’~:~? IC i<br />

mOrus omnls, quam primum per foramen BC traniiit, dilatari incipiet<br />

& ablrlde , tanquam a principio & centTo> in partcs oirmcs<br />

diretie propagari. ,G& El D.<br />

pROPoSITPo XLILI. THEOREMA X<br />

C&S. I: Nam partes corporis trcmuli vicibus akernis eundo &<br />

redeundo, itu fuo urgebunt & propellent parces Medii fibi proximas,<br />

& urgendo compriment eafdem SC condenfabunt j dein reditu<br />

fuo fiuent partes comprefljs rcccdere Qi Cek expandere, Hgitur<br />

partes h4edii corpori tremulo pro::imri ibunt 8; redibunt .per<br />

vices,. ad infiar partium corporis iJiius tremuli: & qua ratione<br />

partes.corporis hujus agitabant hfce hlcdii partes) 11~ fimilibus I<br />

tremoribus agitate agitabunt partes fibi, proximas, ezque fimiliter.<br />

agitatz agitabunt ulteriores 3 k Gc deinceps in infinitum. Et,<br />

quemadmodum Medii partes pritnz eundo condenfantur & re-<br />

&undo relaxantur, fit partes, reliqult quoties eunt condenfabun-~<br />

tur, & quoties redeunt fek expandent. Et pr.opterea non omnes I<br />

ibunt & fimul redibust (fit enim determinatas ab invicem dieantias<br />

krvando, non rarefierent &z condenhentur per vices) fed ac-;<br />

cedendo ad invicem ubi condenijntur, S: recedendo ubi rarefiunt,<br />

aliquaz:earum ibunt dum ah redeunt;..idque vicibus .alternis in<br />

infinitum. Partes autem euntes Sr eundo condenhtz, ob motum<br />

hum progrefivum quo feriunt obfiacula, funt pulhs ; 8~ p.ropeerea<br />

pulf’us fucceiiivi a corppre omni tremulo in dire&urn propagabuntur<br />

j idque aqualibus circiter ab invicem difian,tiis, ob rcqualia<br />

temporis intervalla , quibus corpus tremoribus his hgulis<br />

;fmgulos pulfiis excitat. Et quanquam corporis tremuli partes.eant-&<br />

redeant kcundum plagam aliquam certam & determinatam,<br />

tamen pulrUs inde per Medium propagaci fefe dilatabunt-’<br />

ad latera, per PropoGtionem prxcedentem j & a corpore illo tre-<br />

~~10 tanquam centro communi 3 ficundum fuperficies properno-.<br />

dum fphaericas. & -concentricas., undique propagabuntur, Cujus:,<br />

rei


_ .<br />

UE Moru rei exemplum aIiquo$ habemus in Undis, quz fi di$to tremu~a<br />

E i) 11 P o R u M excitcntur9 non foIum pergen t hint inde fkcundum plagam motus<br />

digiti, red, it1 modum circulorum concentricorym, dlgicum fhtim<br />

ciqent S: undique propagabuwr. Nam gravltas Undarum Cupplet<br />

iocum vis k!IaTticz<br />

cds,t. Qod G h,ledium non fit Ha&urn : quoniam ejus partes a<br />

corporis trcmuli partibus vibratis prefh condenhi IlC'~,Llt?Unt, pro.<br />

pagabitllr motus in infianti ad parres ubi Medium facillimc cedit,<br />

Iloc cfi, ad partes quas corpus tremulum alioqui vacuas a<br />

tergo relinqueret. ldcm efi cafus cum caiu corporis in Me&o<br />

quocunque projek. Medium cedendo proje&ilibus, norm reaedir<br />

in infinitum 5 fed in circulum eundo, pergit ad fpatia quri:<br />

corpus relinquit a terga. Igitur quoties corpus tremulum pergit<br />

in parrem quamcunque, Medium cedendo perget per circu-<br />

]um a,d parces quas corpus relinquit j Sr quoties corpus regreditur<br />

ad hum priorem, Medium inde repelletur & ad loeum fuum<br />

prioreni redibir. Et quamvis corpus trcmulum non fit firmum,<br />

f’ed modis om.nibus flex&, ii tamen magnitudine datum maneat,<br />

quoniam tremorihs fuis nequit Medium ubivis urgere, quill alibi<br />

,eidem fimul cedar j efficiet ut Medium 3 tecedendo a part&us<br />

ubi premirur, pergat femper in orbem ad partes qu;r: eidem cc..<br />

.dunt, g E. 23.<br />

Co&. Hallucinantur igitur qui credunt a.gitationem pa;r.bium<br />

2F’Iammz a,d prefionem, per Medium ambiens, fecund;um~ lineas,<br />

.rc&as~ propagandam conducere. Debebit ejufmodL preiro n.on’<br />

,,ab agitatione fola pastium Flammaz, fed a totius dilataciane d!e&<br />

4wi.<br />

Tnol?osrTIo “XLIV. THEOREMA xxxv.


aritur ab atrritu canalis, hit non confidero. Kkfignent igitur A?~!32 L, I II IT K<br />

CSZ, lT.Xdiocrem altirudineni aqua: in crure Lltroque; & ubi aqU;L scc”KJ’ws~<br />

i-n C~LU-c 1c.L aficndit ad altirudinem E F, dei’ccnderit aqua in<br />

crure MN ad alcitudinem GH Sit autem T corpus pendulum,<br />

?T fliIum, Y pum9xm fufpcniionis~ SP ,qR Cyclois qiiam Pcndul~m<br />

c&$x-ibat, ‘P ejus pun&urn inhum, T g arcus altitudhi<br />

AE xqualis. Vi+ qua motus aqux alternis vicibus acceleratur<br />

& retardatur, .efi cxcefis ponderis aqux in alterutro crux fupr!<br />

pondus in altero, ideoquc, ubi aqua in crure KL akcndit ad IL fi’,<br />

& in crnre alter0 defcendit ad (22’3, vis illa CR pondus duplicat.um.<br />

aqu.az EA?B F, & propterca efi ad pondus. aqtm totius ut<br />

A E feu T $$+ ad VT I’eu TR. ‘Vis etiam, qua pondus !P in<br />

31mzn;, quovis, ~acceleratur & retardatur in Cycloide, (pm Coral.<br />

Prop. L I(,) efi ad ejus pandus totum, UC ejus difiantia “1” 2 a loco<br />

infima I>, ad Cycloidis -1ongitudincm T R. C&are aqua & pcnduli,<br />

azqualia fpitia AE, 2 & defcribentium, vires motrices func<br />

u.lt pondera movenda 5 idc,oque, ii aqua & pendulum in principjo<br />

quiefcunt # vires ilk .movebunt eadem xqualircr tempori-<br />

‘bus xgualibus, efficientque uf: muCu reciproco hul cant & rcdeanr.<br />

g& Ei CD.<br />

CQ~O&, I. Igitur aqua afcendentis & defcenden~is, five motus intenfior<br />

fit five rdmiffior, vices omnes filnt libchron3.z.<br />

CO&. 2, Si longitude aqua totius in canali fit pcdum Tarz$mj&P2<br />

6; : aqua ternpore minuti unius lrecundi dekcndcc, & remv<br />

pore minuti alterius fcccundi akendet; &.fic deinccps vicibus al..<br />

ternis in infinitu~m. Nam pendulum pedum 3 i”U lengitudiais,<br />

telngore rninauti unius fecundi ofcillatur.<br />

Curok.


4 ,<br />

UC r\1orw cof%l $ Au&a alltern vel diminuta longitudinc aqwzy augc.,<br />

Co ‘I” n LJ Iby tur vel diminuitur tcmpus reciprocatiollis in longhldillis ratione<br />

d‘ubduplicata.<br />

PROPQS%TIQ XIX THEOREMA XXXVI.<br />

,<br />

r~~d&+~~~~~ ;veh~t~ eJ in Jitibduplicuta rutione latitudinum<br />

c;ollfcquitur ex confiru85one Propofitionis fequentis.<br />

‘P~IJX’~SITIQ XLVI. P.ROBLEMA Xw<br />

.kzlenit+e velocitgtew<br />

Undawm<br />

‘GoonHhatur Pendulum cujus longirudo, inter pun&Lam fu&e~~<br />

fionis SL centrum ofcilhtionis, zquetur latitudini Undarum : SC quo<br />

tcmyore pendulum illud ofcillationes hgulas peragit, eodem Un-<br />

& progredicndo Iatitudinem ham propemodum conficient.<br />

Undarum Iaritudhem voco menhram tranfverfh, quae vel vallibus<br />

his, vcl fummis culminibus interjacet. Defignet ABC’P)EF<br />

fiiperficiem aqua -Itagn;lntis , undis firccefflvis afcendentem ac defy<br />

ccndentem j htque A’, C, E, &c. undarum culmina, & B,D, F, &c,<br />

,valles intermedii. Et quoniam motus w~darum Iit per aquk I&-<br />

cefflvum afienhm & defcenfum, fit uli: ejus partes A,C, E, &c.<br />

quz nunc altifimx funt, mox Gant infimz j & vis. motrix, ‘qua<br />

partes altifimze defcendunr & infimx afcendunt, eft pondus aqua:<br />

clevatll: j alternus ilk afcenhs & defienfils analogus erit rnottii reciproco<br />

aqux in canali , eafdemque temporis Jeges obfervabit: &<br />

proprerea (per Prop. XLIV) ii difiantiaz inter undarum ‘loca altif-<br />

$ma A, CJ E *& i&ma B,‘i!I,F zquentur dupke penduli longitudini<br />

; parrcs altiflimx A, C, E;tempore’ okillationis unius evadent<br />

infimz, & tempore ofcillationis alterius denuo afcendenr. Jgitur<br />

inter tranfirum Undarum fingularum tempus erit ofcillationum<br />

duarum j hoc efi, Wnda defcribet latitudinem fuam, quo tempore<br />

pendulum illud bis ofcillatur ; fkd eodem tempore pendulum, cujus<br />

longirudo quadrupla efi, adeoque xcpt undarum laticudinemJ<br />

rjfcillabitur $kmel. &.E, .I.<br />

Carols I. Igitur, Undz, quz pedes !Par@$es 3 A8 law iunt,<br />

‘km~ore minuti unius fecundi progrediendo latitudincm ham con-<br />

‘ficiew 5 adeoque tempore minuti unius priki .percwrrent ,pedes<br />

J $3 f-, & hors fjpatio pedes z LOW quamproxime.<br />

Coral. 2.


PRIN CIPIA MATHEMATICA. 3 j7<br />

Cored. 2. Et undarum majorum vel minorum Ye- L in 1:~<br />

locitas augebitur vel diminuerur in fubduplicaca ’ cc”‘i ““*<br />

ratione Iatitudinis.<br />

Ekec ita k habent ex Hypothefi quad partcs<br />

aquas r&a afcendunt vcl r&a defcendunt; i‘cd<br />

afcenfh & dekenfus ille verius KC per circulum,<br />

-<br />

ideoque tcmpus hat Propofitione non ilili qu,!iliproxime<br />

definitum efk a&no.<br />

PR 0 P. XLW. THE 0 R. XXXVII-<br />

Pu@4.r per Flbtidum propugutis ) Jingh liluidi<br />

partic&, wotu reciproco hwu$no euntes d?<br />

redemces, accelerantur Jemper C$ retnrdnntcw<br />

pro legc ofiillantis Pendtili.<br />

Dcfignent A 13, B C, CD,<br />

kc. pulfuum fucceffivorum<br />

azquales difiantias j AI3 C<br />

plagam motus pulfuum ab<br />

A verlus B propagati j E,<br />

P, G punCt-a tria Phyfica Me-.<br />

dii quiefcentis, in re&a AC<br />

ad zquales ab invicem difiantias<br />

f’ita ; E e, Ff; Gg,<br />

fpatia aqualia perbrevia per<br />

quz pun&a illa motu reciproco fingulis vibrationibus<br />

eunt & redeunt j E) p, y loca quzvis intermedia<br />

eorundem pun&,orum ; & E F3 FG lineolas<br />

Phyficas feeu Medii partes lineares pun&s illis interje&as,<br />

& fucceflive tranflatas 111 loca eq3, p 31 &<br />

ef, fg. Re&z E e aqualis ducatur reLIta F S.<br />

Bikcetur eadem in 0, centroque 0 & intervallo<br />

0 P decribarur circulus S.lT’P. Per hujus circumferentiam<br />

totam cum partibus Cwis exponatur<br />

tempus totum vibrationis unius cum ipfius partibus<br />

proportionalibus ; fit W complete tempore<br />

quovis “p H vel T lfS15 3 G demittatur ad T S<br />

perpcndiculum I-IL vel S.4 & capiatur E B aqualis<br />

T L vel T Z, punRurnX~hyficum E reperiatur<br />

,’ in


&cc]erationis ac rctardationis gradibus v~brat~ones<br />

fiJlgu]as peraget cum okillante Penduls. Vrobandum<br />

cfi quad fingula Mcdii pun8a PhyIica<br />

tali rnrm agicari debeant. Fingamus igitur hledium<br />

taIi motu a caufa quacunque cieri, 6s. videamus<br />

quid inde fequacur.<br />

In circumfcrcllci.2 ‘P HSb capiantur 32quales nrcus<br />

12% IK wl hi, ;k, earn Itahenres ratiorrem<br />

ad circumkrcntiam totam quam l~abent xqualcs<br />

reck E.$‘, FG ad pulhum intcrvallum toturn<br />

A!3 c’. Et dcmifis perpcndiculis Ilk, .?i;N vcl<br />

in, kn j quoniam pun&a E, F, G motibus Gmilibus<br />

Eiccefive agitantur, & vibrationes Puss integras<br />

ex itu & reditu conzpofitas inserea peragunr clum<br />

pulh transferfur a B ad C;<br />

ii “P P-p vel “Y HSb fit ternpus<br />

ab initio motus pun&h<br />

E, erit P 1 vel ‘P H Si sempus<br />

ab initio niotus pun&i<br />

& & TK vcl T HSR ternpus<br />

ab initio morus pun&i<br />

G ; & prapterea E e, Fp 9<br />

G y ~erunt ipfis Y’ L, 13 M,<br />

TN in itu pun&orum, vcl<br />

P<br />

ipfis I”!, Tkz, Tn in pun&orum rcditu, XTpJa-<br />

Its refpetiive. Unde ty feu EG+Gy-EE<br />

in iru pun&orum zqualis erit E G - LA?, in IXditu<br />

autem Equalis E G +h. Sed ey latitude CR<br />

62.1 expanfio partis Medii E G in loco ey; 8~<br />

propterea expanfio parris illius in itu, cfi ad ejus<br />

expalllionem mediocrem 9 UC‘ EG-LN ad EC>;<br />

ia ,reditu autem ut E G -/-Zn feu E G +.L AT ad<br />

EG. C&we cum fit LN ad 1C.H ut,l&? ad<br />

radium 0 P3 & KH acl E G ut circumkrcntia<br />

THShT ad B C’, id efi (ci ponatur V pro ra-<br />

530 circuli circumfercWiam hnbentis 3.2qualcm h<br />

tervallo pUlfUU~~ EC) Lit OP ad Vj Sr CX LtZ-<br />

quo L N ad E G, ut .liW ad<br />

pais EG pa n 19 -he Phyki F


I<br />

-qzi<br />

ad 6. Et eodem argumento vires cIafiic;r punfiorum<br />

hyficorwm E & G in itu, fiint: ut<br />

v-;rlL 8r v -;\ iv<br />

I+ Sr virium differentia ad hledii vim e]aflicanl mediocreIn><br />

3s limites vibrationum) fupponamus HI, tk KN indefinite<br />

illores eire quancitate V. Quare cum quantitas V dew, di@entia<br />

virium efi Ut NL - KN’, hoc efi ( ob proportionales<br />

‘L -.KN ad HX, & 0 M ad 0.1 vel 0 P, datafque HK &<br />

!P) ut OM; id efi, ii Ff bifecetur in a, UC R C+ Et eodehl<br />

gumenco differcntia virium elafiicarum punaorum Phyficorum<br />

k y, in reditu Iincola: Phyficz cy elt ut tiq. Sed dlffercntia<br />

2 (id efi, exceffus vis elafiica pun&i E fupra vim elafiicam puni<br />

7,) efi vis qua interjeQa Medii Iineola Phyfica E y acceleratur 5<br />

prapterea vis acceleratrix lineok Phyficz E yy efi ut ipiius ditntia<br />

a media vibrationis loco a. Proindc tempus (per Prop.<br />

;XVIII, Lib. I.) retie exponitur per at-cum T I; & Medii pars<br />

learis E y lege prazkripta moverur, id efi, lcge ofcillantis Yen-<br />

Iii : efique par ratio partium omnium liflcarium ex quibus Meurn<br />

totum componitur. Ji$lvD.<br />

Cared. Hint paret quod numerus pulfuum propagatorum idetx~<br />

cum numero vibrationurn corporis tremull, ixque mulriplic;lr<br />

in carurn progreiru, Nam lineola Pbyfica E y, quamprimum<br />

locum fiwm primurn red&it, quiefcet j neque deinceps move-<br />

:ut nifi Tel ab impetu corporis tremuli, vel ab impetu pulhuut~~<br />

i a corpore tremuI0 propagancur, motu nova cieatur. Quic-<br />

:t igitur quamprimum pulfIls a corpore tremulo propagari<br />

Gnunt,<br />

xx2 . PK0P0-


1>f41J;j:rti2 in; g;l~ido H6$co propagutorum *elocitates, J&t in ratiovjz<br />

compo(ita ex Jubd[dplicstcz ratione ;th Ela/ih dzveze &I+<br />

J&hplicar~ rutione denJitatir iwuer/e 5 k modo Fhtidi vis<br />

E;/aj$ca Qldfdem condmjkioni proportlomh ele ~tipponutzar.<br />

c;z/. I. Si hlcdia fint homogenea, tk puli’uum diltaneiz in his<br />

h;%ediis zqerencur inter fc, fed mows in uno Media intenfior fit:<br />

conrraEtiones & dilatationes partiurn analogarum erunt ut iidem<br />

IPYOtUS. Accurata quidem non elt h~c proportio. Serum tamen<br />

niii contra&iones & dilacationes lint valde inrenfz, non errabit<br />

knfibiliter , ideoque pro Phyfice accurata haberi potek SLUYC<br />

autcm vires EIaRicx matrices ut concra&iones & dilatationes; &<br />

velocitates partium azqualium fimuI gcnitaz fimt L1t vires, Ideoque<br />

zquales & correfpondentes pulfuum correi‘pondentium partes,<br />

itus & reditus iilos per fparia contra&ionibus St dilatationibus<br />

proportionalia , cum velocitatibus quaz funt ut Cpatia, fimul peragent<br />

: 8~ propterea pulfus, qui rem pore itus &C reditus unius latitudinem<br />

i‘uam progredicndo conficiunt, & in loca pulfuum proxime<br />

pr,rcedentium femper fkcedunt, ob ;Rqualitatem difiantiarum,<br />

aquali CLI~I velocitate in Medio utroque progredientur.<br />

C’aJ 2. Sin pulfimm diitantiaz ku longitudines fint majores in<br />

uno Medio quam in altero; ponamus quod partes correfpondentes<br />

fpatia latitudinibus pulfuum proportionalia fingulis vicibus<br />

eundo & rcdeundo defcribant : & zqwales erunt earum contra-<br />

Lkiones & dilatationes. Ideoque fi Media fint homogenea, aqua-<br />

Its erunt etiam vires illa: Elafiic;x: matrices quibus reciproco motu<br />

agitancur. Materia autem his viribus movenda, eft ut pulfium<br />

latitude j & in eadem ratione elE fpatium per q~od fingulis vicibus<br />

eundo & redeundo moveri debenc. EBque tempus itus &<br />

reditus unius in rationc compofita ex racione firbduplicata mate-.<br />

fix & ratione iubduplicata fpatii, atque adeo ut fpatium. Pulfus<br />

autcm temporibus itus & reditus unius eundo latitudines fuss<br />

oonficiunt, hoc efi, fpatia temporibus proportionalia pcrcurrunt;<br />

& proptcrea fiunt zquiveloces.<br />

CL@ 3, In Mcdiis igitur denfitate & vi Elafiica paribus, puIfUs<br />

omnes iirnt zcquiveloces. Qod fi Medii vel denfitas vel vis Elaitica<br />

intendatur, quoniam vis matrix in ratione vis ElaAiw, &<br />

matcrin movenda in rationc dcnfitatis augctur 3 tempus quo motUs


PROPOSYI’rO XLIX. PROBLIZMA XI.<br />

~a& Me& dtw@ate & vi ElaJica, invenirl? ruclocitnfrm pd-<br />

s Uldrn.<br />

Fingamus Medium ab incumbentc pondere, pro nlorc ACris<br />

nofiri comprimi 5 fitque A alricudo Mcdii homogenci, c11.j~ ~OII -<br />

dus adzquet pondus iacumbens, & cujus denIit;ls cadcnl lit cum<br />

denfitate Medii comprefi, in quo pul~uus propaganrur. Chnflitui<br />

autem intelligacur PenduIum, cujus loljgitudo inccr ~~un~kum<br />

Eufpenfionis & ccntrurn ofcillarionis fit A : & quo tcmporc Pendulum<br />

illud ofcillationcm integram cx icu & rcditu compoiit:lm<br />

peragit, eodem puMi~ eundo conficiet fpacium circunz~~rcnti;~<br />

circuli radio A defcripti ~qualc.<br />

Nam itantibus qua in Propofitiolle xLvxl con~ru~92 hJt3<br />

fi linea qwzvis Phyfica .E I;; fingulis vibrationibus dcf~ribcx~do<br />

fpatium ‘PS, urgeatur in extremis itus & reditus cujui$uc loch<br />

T & 8, a vi. Elafiica qu32 ipfius ponderi xquetur; pcragct h:w<br />

vibrationes fingulas quo ternpore eadem in Cycloidc, cujus pcrimeter<br />

tora longitudini 233 gqualis efi, ofcillnri pofl’ct : id adco<br />

quia vires aquales zqualia corpufcula per zqualia 43atia fimnl impt2lleXlt.<br />

C&are cum ofcihtionum tempora fint in iirbdupliwt:~<br />

ratione longitudinis Pendulorum, & longicudo Penduli :c~~uccur<br />

dimidio arcui Cycloidis totius; foret tcmpus vibrationis wius ;KI<br />

tempus ofcilltitionis Penduli cujus longitudo eil A, iu itibduplicata<br />

ratIone longitudinis t 5? S iEu P 0 ad lungitudinem A, Scd<br />

vis Elafiica qua lincola Phylica E G, in locis iiS cxtrcmis I”, J<br />

exifiens, urgetur , erat (in demonfirationc Propofitionis ~1.~1 I><br />

ad ejus vim toram Elafiicam ut Hi5 -Kiv ad v , hoc ell:<br />

(cum pun&urn X jam incidat jn T) ut HA’ ad V : & vis illa<br />

tota, hoc eit: pondus incumbcns, quo lincola IL 0 Cc~rnprir~itur~<br />

efi ad pondus 1incoIa: LX pondcris incumbcntis nlticudo A ad lilacoh<br />

longitudincm E G; adeoque cx zquo, vis qua lincoh h” C in<br />

locis his ‘FJ St S urgecur , cfc ad lincolx ilkus po~~dus ut 1$1%X. A.<br />

ad V %I2 G, five ut TO x fl, ad V If3 mm l2.K crac ad b’G ut<br />

P 0


I?I-I’I[LC3SOI’E-II& NATURAL-as<br />

nE ,IF,~~ u 7’0 ad V. Q.nrc cum tempera, quibus qualia corpora per<br />

4:oRI’*1:L!~1. ryilual~a fpatia impelluntur, fint reciproce in fubduplicata raeionc<br />

viriun3, erit ternpus vibracionis unius urgente vi illa Elafiica, ad<br />

tempus vibrationis urgente vi ponderis, in fhbduplicata ratione<br />

V V ad fpQ x A, atque adeo ad tetnpus okillationis Penduli cujus<br />

longitude et% A, in hbduplicatn ratione V V ad fp 0 x A, &<br />

[ubdupllcata rationc T 0 ad A conjun&im; id et?, in ratione intcgra<br />

V ad A. Sed tempore vibrationis unius ex itu & reditu compofitx,<br />

pulfus progrediendo conficit latitudinem ham B C. Ergo<br />

rempus quo pub percurrit iparium BC, efi ad ternpus ofcillatL<br />

onis unlus ex itu & reditu compofitz, ut V ad A, id CR, ut BC<br />

ad circumferentiam circuli cujus radius efi A. Ternpus autem,<br />

quo puifus percurret fpatium BC, efi ad tempuo quo percurret<br />

longitudinem huic circumferentiz zqualemr in eadem ratione;<br />

idesque rempore talis ofciIlarionis pulfus percurret longitudinem<br />

111uicircumferentk xqualem. ,$&E. 22.<br />

Cord. I. Velocitas Pulfuum ea eQ quam acquirunt Gravia,zqualiter<br />

accelerate motu cadendo, & caCu ho dekribendo dimidium<br />

alticudinis A. Nam temporc cafus hujus, cum velocitate cadendo<br />

acquifita, pulfis percurret fpatium quoci. erit aquale toti altitudini<br />

A, adeoque tempore okillationis unlus ex itu & reditu com-<br />

~ofiw, percurrct fpatium ayale circumferentia circuli radio A<br />

defcripri: efi enim tempus cabs ad tcmpus ofiillationis ut radius<br />

clrculi ad ejufdem circumferentiam,<br />

Cwol. 2. Unde cum altitudo illa A fit ut Fluidi vis ElaRica diretie<br />

& de&as ejufdem inverk; velocitas yulfuum erit in ratione<br />

compofita ex fubduplicata ratione denfitatis inverk & f’ubdupli-<br />

.cata ratione vis Elafiicz dire&e,<br />

Corporis, cujus tremore Pulfus excitantur, inveniatur numerus<br />

Vibrationurn data ternpore. Per numerum illurn dividatur fjparium<br />

quad pulfus eodem tempore Percurrere pofk, & pars inventa<br />

erir pulfus unius latitudo. &E. 1.<br />

Spe&ant Fropofitiones noviff~mx ad motum Lucis & Sonorum,,<br />

kux enirn cum proyagctur kcundum lineas re&as, tin &Zone ibla<br />

(Per


343<br />

(per Prop. XL!, & XLII,) .confiltere nequit. Sonivero propterc;:a r,ll~Vl~<br />

qtJOd 3 corporibus tremuh oriantul -, nihil allud itlot quam aerl~ SI,~~~KI) ~JS,<br />

pulius propagati, per Prop. xI,lr 1. Confirmatur id ex tremoribus<br />

quos excirant in corpori bus obje&is, fi modo vehementes fint 6(<br />

gl+as7c~, ~LLIJCS fint foni Tympanorum. Nam tremores ccleriorcs<br />

& breviores dlfhilius excitantur. Scd & Cones quoI‘vis, in chordas<br />

corporib~~s fonoris unifonas impn&os, CXCitWC trcmores IlotiG<br />

fim~lm efi, Confirmatur etiam ex velocitatc fonorum. Nan1 cllln<br />

pondera fpecifica Aqu”: pluvialis & Arger:ti vivi lint ad inviccm<br />

ut 1 ad 13: circiter, & ubi Mercurius in .&woriaelro alcitudilwn<br />

attingit digitoru,m Anglkcorum 30, pondus fpecificum Aeris fir<br />

aqutl; pluvialis fint ad invicem ut I ad 870 circitcr : crunc l)ondera<br />

Qecifica aeris,& argenti vivi ut 1 aa 11890. Yroillde cum<br />

altitudo argenti vivi fit 30 digitorum, altitude aeris unifi>rmIs,<br />

cujus pondus aerem nofirum ihbjeAum comprimcre polkt, crie<br />

3 56700 digitorum, feu pedum ffnglisortim 2972 5. hflque IIXC<br />

altitude illa ipfa quam in confiruhone hperioris Problemn.tis nominavimus<br />

A. Circuli radio 29725 pedum dofcripti circumfcrcntia<br />

efi pedum 186768. Et cum Pendulum digitos 3@ longumg<br />

okillatio~nem ex itu & reditu compofitam, tempore minutc)rum<br />

duorum fecundorum, uti notum efi, abfolvat; Pendulum pcdes<br />

29~725~ feU digitos 356700 lOngUn1 , ofcillationcm coniimilem tcmpore<br />

minutorum fewrldorum 130: abfolvere debebit. Eo igitur<br />

tempore ibnus progredkndo conficict pedes I 86768, adeoque<br />

ternpore minuti unius kundi pedes 979,<br />

Csterum in hoc compute nulla habetur ratio craffitudinis fijIi--<br />

darum particuIarwm aeris, per quam fonus utique propni;:ltur ill<br />

infianti. (3um pondus aeris fit ad pondus aqua ut E ad 870, :k<br />

files fint fere duplo denfiores quam aqua j ii particulx acris PC.,-<br />

nantur effe ejufdem circiter denfiraris cum p;tr*ticulis vcl aqux<br />

vel falium, & raritas aeris oriatur ab intervallis particL~l;~rulll :<br />

diameter particulz aeris erit ad intervallum inter centra llarticularu,m,<br />

uo I ad 3 vel xo circicer: & ad intervalIum inter plrn--<br />

ticulas ut I ad 8 vel 3” Froinde ad pedcs 97y qu0.s foritls mlpore<br />

minuti unius kcundi juxta caIcuIum iLlperiorcnl corlficict 9<br />

addere lket pedes y feu ICY circkcr, ob craflirudincrn p:lrticularum<br />

aeris : 8r iic ionus temporc mirluti unius ricL]ndi c[,rlficict<br />

pedes 1088 circiter.<br />

His adde quad vapores in aere latentes, cum cnt alter;us clateris<br />

& akerius toni, vix aut ne vix quidem pal’ti~ip;l~lt lllo~llm<br />

aeris veri quo foni propagantur. J-b tlutem quickcntibus, mo-<br />

bl!S


Sit A FL Cylindrus uni-<br />

formiter circa axep S in orbem<br />

a&us, Sr circulis concentricis<br />

B G M, (I HA?,<br />

523 IQ, .,EKT, &c. diftingua<br />

tur, Fluidum in O&es cy-<br />

lindrkos innumeros concentricos<br />

folidos ejufdem craffL<br />

tudinis. Et quoniam homogeneurn<br />

efi Fluidum 5 im-<br />

grefliones contiguorum Qrbium<br />

in fe mutuo fkSt.lk 3<br />

erunr (per Hy@thefin) ut<br />

eorum tranflationes ab invicem & fiperficies contiguaz in quibus<br />

impxeffbnes fiunt, Sijmprdio in Orbem aliquem major efi vef.<br />

YY<br />

nninor


346 I.‘HIL~SOPHIA Na,TURALLf<br />

11 f; MOTU minor e’x parte concava qUam ex parte convexa 5 prLxmkbit h-<br />

‘OR“OR”” preilio fortior, R mown Orbis vel accekrabit vel retardabit,<br />

prout in enndem regionem cum ipfius mote vel in contrariam dirigitur,<br />

Proinde IX Orbis ur,ufquiTquc in motu fuo uniformiter<br />

pcrfevercc,,debent impreiliorles ex parte utraque fibi invrcem aquari,<br />

& fierl in regiones cotmnrixh Unde cum imprefioncs iir~lt Ut<br />

conr~gu:~ filperficics & harunl tranilationes ab invlcem, erunt tranflationes<br />

inverk ur ltiperficies, hoc efi, inverfe ut dilperkierum dilh~ti;l:<br />

ab axe. IF’~llt autcm dkY”erentiaz motuum angularium circa<br />

axem UC !IX tranflationes applicatz ad d&an&s, five ut tranilariones<br />

direLk:te or diRanti;z inverk; hoc efi (conjun&is rationibus)<br />

ut quadrata dif’tantiarum inverfk. C&are ii ad infinit;x: reQae<br />

S A 13 C 23 E g parres fingulas<br />

erigarltur perpendicula<br />

Aa, E’b, Cc, Bd, Ee, kc.<br />

ipkrum ,$‘A, SB, J’C, SD,<br />

J’E, &c, q”;ldratis reciproce<br />

proportionalia, & per rer- 15<br />

minos pcrpendicularium du- i<br />

ci intelhgatur linea curva :<br />

Hyperbolica; erunt fiirnmaz i<br />

difikrentiarum, hoc efi, mo- :,<br />

tus tori artgulares, ut re- S<br />

fpondentes i~tl~m~ Jillearum ’<br />

An, Bb, Cc, CDd, Ee: id<br />

.-..&... ,..,*r**<br />

efi, fi ad conitituendum Medium<br />

uniformiter fluidurn, Orbium numerus augeatur & latitudo<br />

minuatur in infinitum, ut area: Myperbolicae his fummis analog=<br />

~.A&.$& Bb,$& Cc&DdL& Ee$& &c. Et tempera motibus angularibus<br />

reciproce proportionalla, erunt etiam his .areis reciproce<br />

proportionalia. Efi igitur tempus periodicum particul;t: cujufvis<br />

fD reciproce ut area 2) dR, hoc efi, (per notas Curvarum quadraturas)<br />

dire&e ut difiantia SD. ,$!& 23. ?I*<br />

Cwok. I. Hint motus angulares parcicularum fluidi fknt reciproce<br />

ut ipfirum difiantiz ab a,xe cyIindri> & velocitares abfoluta2:<br />

iirnt aquales.<br />

Coral. 2. Si Auidum in vak cylindrico loragitudinis infinite contineatur<br />

), & xylindrum alium interiorem contineat, revalvarur<br />

riutem cylindruk utergue circa axem communem, fintque ~evolutionuw


Eionum tempera ue igforum femidiametri, 9r perfeveret fluidi pars L.1arz.n<br />

ul3aquzque in mocu Co : erunt partium iingu,larum cempora pcri- s cC” N” “”<br />

odica ut ipfar’arum difianck ab axe cyIirtdrorum.<br />

C”oroZ. 3, Si cylindro & fluid0 a,d hunt modum motis addatur<br />

vel auferatur communis quilibec motils anguIasis 3 quoniam hoc<br />

nova motu non mucatur attritus ml~tuus parcium fluidi, non mu- -<br />

tabulltur rnotus partium inter Ce. Nam franflariones parciurn a!3<br />

invicem pendenc ab attritu. Pars quzliber in eo perieverabit<br />

rnotu, qui, attritu utrinque in conrrarias partes fatio, non magi5<br />

acceleratur quam retardatur.<br />

CbroZ. 4, Unde G toti cy1indrorum.k fluidi Syfiemati auferatur<br />

motus omnis angularis cylindri exterIoris, habebitur motus fluidi<br />

in cy lindro quiefcente.<br />

Coral. f. Egitur ii fluid0 & cylindro exteriore quiekentibus, revolvacur<br />

cylindrus interior uniformicer ; communicabicur motns<br />

circularis .fluido , & paulatim per totum fluidum propagabirur 6<br />

net prius definct augeri quam fluidi partes fingulaz motum Corollario<br />

quart0 definicum acquirant.<br />

CoroZ. 6. Er quorriam fluidum conatur motum fuum adhuc latius<br />

propagare , hujus imperu circumagetur eriam cylindrus exterior<br />

nifi violenter detentus ; sz accelerabitur ejus motus quoad ufque<br />

tempera periodica cylindri utriufque zquentur inrer k. C&od G<br />

cylindrus exterior violenter detinearur, conabitur is motum Auidi<br />

retardare; & nifi cylindrws interior vi &qua extrinfecus imprefi<br />

motum illum conkrvet, efficiet ut idem paulatim cefit,<br />

ae omnia in Aqua profunda fiagnante experiri licet.<br />

PROPOSI~IO LII. THEOREMA XL.<br />

C&s. X. Sit A FL Sphzra uniformitcr circa axem S in orbem,<br />

a($;r, & circulis concentricis BG’M, G E-fd\d, PIQ, E di:T, &c,<br />

-n 2 diltin-


348<br />

biflinnuatur h;]uidum in Orbes ifxiumeros COlmntriCOS ejufde&<br />

DE i+tlOTU<br />

C:ORI~OSUM cmfli[Zdinis. Fillge autenl Or*he~ !IlOS efie folidos 5 & quonjam<br />

I~~moge~~eun~ efi E;luidum3 imprefllony contiguorum ~rbium in<br />

ik mutuo fa&x, erunt (per Hypotl+II) UC eorclm tranilationes<br />

ab invjc-m & iilperficies COlltJgU3”, lfl qUibUs impdhncs fiunt.<br />

Sj jmprefio in Orbem aliquem major eit.vel m$lor ex par&Z con-<br />

~a172 cpi21 ex parte ccmma; pr337alebit nnpefllo f0rti0r, 8-z vcl+<br />

citatem orbis vel accelerabit vel retardabit, prout in eandem rcgionen<br />

cum ipfiu(; n~ocu vel iI1 conerariam dirigitur. Proinde ut<br />

Chbis unufquiiijue in nnotu Co perfeveret unifkniter, debebunt<br />

Jr~jprefiQnes ex parce u traquc fibI invlcem squari, 6r: fieri in re-<br />

@ones conrrarias. Unde cum impr&iones iint .ut contiguz finyerficies<br />

8; harum tranflationes ab invicem ; erunt tramflationea<br />

iIlver[e ut fuperhcies, hoc eit, inverfe ut quadrata difiantiarum muperficierum<br />

ci centro. Sbanr autem dlfferentix motuum angularium<br />

circa axem ut b3: tranflationes applicntz ad diftantias, five uc:<br />

cranflationes dire&e & difiaxltk inverfe j hoc efi (conjunCtis ra;<br />

tionibus ‘, LIE cubi difiantiarum inverk Qgare ii ad re6ke in&<br />

nita: JAB C‘D E 2, partes fingulas erigantur perpendicula A&,<br />

Bb, CC, Dd, Ee, &c, ipkum S.4 J’& 4% SD. SE, kc;<br />

cubis reciproce proportionalia , erunt fumm~ difkrentiarum, hoc<br />

efi, mows rori angulares, ut refpondentes fumrnz Iinearum ~a,<br />

Sb, Cc, IDd, E e: id efi (ii ad confiituendum Medium uniformi;<br />

ter fluidurn, numerus Orbium au&eatur F latitude minuatur in infinitum)<br />

ut are;l: Hyperbolicz Ials fumrnls al?alogx nag9 B b R,<br />

Cc& Zld,@ Ee&&c. Et tempora p!rlodica motibus angularibus<br />

reciproce proportionaliaj erunt etra? his areis reciproce<br />

proportionalia. Kill: igitur tempw periodlcum Orbis cltjufvis<br />

D 10 ‘reciprocc ‘ut area 9 d& hoc efi, (per notas Ourvarum<br />

quadraturas) dire& ut quadratum difiantis 5’23.. ,Id quad vohi<br />

yrimo demonfirare,<br />

Cns. 2. A centro Spharae ducantur infinitz re&3c: quqm pIuri*<br />

MX, quaz cum axe dates contineant atlgulos, xqualibus differenriis<br />

& mutuo fuperantes j. & his reL?is,cn32 axem, revolupis co,n&pe<br />

Orbe$ in annulos innumeros feCar1; & aWU.hs .unufqujfque, habebit<br />

annulos quatuor fibi contiguos, unum interiorem> aIterum +x#<br />

geriorem SC duos laterales. Attritu interioris & extcrjorjs flbn<br />

potefi annulus unufquifilue, nifi in motu ,juxta Iegem cafus primi<br />

&20, zzecjualirer & in parces contrarias’ urgeri. i Pa&t hoc ex ,dkmonfiracisne<br />

SINUS pri,mi. Et propterea annuIorLzm feries qu%libet.’


pp~~cmA MATHEMATIcA. 349<br />

a Glob0 in infinitUtl1 relta pfX,f$llS, movebitur pro lege cafius pri- LIUE!ir<br />

At SECUXUWZ,<br />

mi, niG quatenus impcditur ab attritu annulorum ad latera.<br />

ill rnotu hat lege fdl-0, atcritus ~?lilUloralm ad latera nullus efi;<br />

Ileque adeo ~noIum~ quo mit7US 11x lege fiat, in7pedieL si annuli,<br />

qui a centro xqualiccr diftant, vcl oitius rcvoIverentiir vi‘1<br />

tardius juxta poloc 3 quam JllxCa t~quatorcnl ; t3rdiores accelerarentw,<br />

s-(- vclociores retardarcntur ab cattritu muruo, & fit verge-<br />

- rem fernper tempera periodica ad aqualirarcm, pro lege cabs<br />

primi. Non impedit igitur hit attritus quo minus motus fiat k-<br />

cundum legem cabs primi, & propterea lex illa obtincbit: hoc<br />

d%, anntdorum iinguIoru~?l D3l~pcX~ periodica crunt ut qundrdra<br />

difiantiarum ipibrutn 2 centro Globi. Qod volui fecundo denl&ff<br />

rare.<br />

C’CZS. 3. Dividatur jam annulu~ unuiquifque h%onibus trad.<br />

verdis in particulas innumeras conitituentes f+ubfiantiam abioluge<br />

& uniformieer Auidam; Sr quoniam ha: Cetiiones non Cpe&ant ad<br />

legem mow6 circularis, fed ad conO+itutionem FJuidi iblummodo<br />

conducunt, peri‘everabit motus circularis ut prius, His kfiionibus<br />

annuli omnes quam millimi a&eritatem 632 vim attritus mutui aw<br />

non mutabunt aut mutabunt zqualiter. Et manente caui5rw-n<br />

proportiane manebic efi2&~rum proportio, hoc efi, proportio rnotlnum<br />

S= periodicorum temporum. L&,E.2).. Czterum cum mows<br />

circular&, & abinde orta vis centrifuga, major fit ad Ecfipkam<br />

quam ad Poles j debebit caufa aliqua adeire qua particulx iingula:<br />

in circ,ulis fuis retineantur J ne maceria quaz adEclipticam eft, recedat<br />

timper A centro & per exteriora Vorricis mig$et ad Poles, indcque<br />

per axem ad Eclipticam circulatione perpetua revertarur.<br />

708. I. Hint motus angulares partium fluidi circa axem globi,<br />

fht reciproce ut quadram diftantiarum ,i centro globi, 8~ velocieates<br />

abi’olutz reciproce ut eadem quadrata applicata ad difiantias<br />

ab axe. ,’<br />

.C’QY$. 2. Si globus in fluid0 qgiefcente fimilari et infinico circa<br />

axgn pofitione datum uniformi cum motu yevolvatur, cWrlmunil<br />

c+irur, motus flwfdo in morem Vorticis, & motus ifitc p~~ulacim<br />

propagabitur in infinitum ; neque prius ceffabit in firlguhs fluidi<br />

partibus accelerari, quam tempora period+ hgularum partium<br />

fint ut qpa&ata di&m$arum ‘5 cemro &hl.<br />

CO&, ZJ~:’ Qy++n Vorticis partes il+kores ob majorem ham<br />

velpcicatenn. atterunt CTS; urgent exteriorcs, motumq~ie ipllis ea a&icme


DE ?dDTIl one perpetuo communicant, & exteriores ilfi eandem motus quanc<br />

0 R I’ 0 R u >I. titatem in alias adhuc exteriores fimul transferunt, caque a&one<br />

fkrvant quantitatern motus i”ui plane invariatam; patet quad motus<br />

perpetuo transfercur 3 centro ad circumferentiam V orticis, 8~<br />

per infinitatem circumfcrentk al+rbetur. Materia inter I+hzricas<br />

duas quafvis i‘uperficies Vorrlci concentrlcas nunquam accekrabltur,<br />

eo quod motum omnem h mate& interiore acceptum<br />

transferc femper in exteriorem.<br />

c’o&. 4, Proinde ad conkrvationem orticis confianter in eodem<br />

movendi fiatu, requiritur principium aliqu@ a&ivum, $ quo<br />

glohus eandem fern per quantitatem motus fcciplat, quam imprimit<br />

in maceriam Vorticis. Abfque tali princtplo neceffe efi LIC globus<br />

&,Vorricis partes interiorr-s, propagantes kmper motum fium in<br />

exteriores, neque novum aliqucm morum recipience% tardefcanc<br />

paularim & in urbem a$ cMifX.Ult.<br />

CO&. 5. Si globus alrer huic Vortici ad certam ab ipfius centro’ ’<br />

gilifiantiam innataret, & interea circa axem inclinatione datum vi’<br />

aliqua confiarnter revolveretur j hujus motu raperecur fluidum in<br />

Vorticem: & primo revolveretur hicvortcx novus 8r exiguus una<br />

cum globo circa centrum alterius, & inrerea latius krperet ipfius<br />

motus, & paulatim propagaretur in infinitum, ad modum Vorticis<br />

primi. Et eadem ratione qua hujus globus raperetur motu Vorticis<br />

alterius, raperetur etiam globus alterius motu hujus 9 fit ut<br />

globi duo circa intermedium aliquod pun&urn revolverentur, feque<br />

mutuo ob motum illurn circuIarem fugerent, nifi per vim<br />

aliquam cohibiti. Poitea ii vires confianter impreik, quibus<br />

globi in motibus fuis perl”everant, ceffarent, 8c omnia legibus Mechanicis<br />

permitterentur , languefceret paulatim motus globorum<br />

(ob rationem in Coral. 3, & 4. afflgnatam) & Vortices tandem<br />

conquiefcerent.<br />

Carol. 6. Si globi plures datis in locis circum axes pofitione datos<br />

certis cum velocitatibus conitantec revolverentur, fierent: Vore<br />

tices totidem in infinitum pergentes. Nan1 globi finguli, eadem<br />

ratione qua unus aliquis motum iuum propagat in jnfinitum, propagabunt<br />

etiam mow fuos in infinitum, adeo ut fluidi infiniti<br />

pars unaquzque eo agitetur motu qui ex omnium globorum a&iionibus<br />

refulrat. Unde Vortices non definientur certis limitibusj,<br />

fid in Ce mutuo paulatim excurrent; globrque per aQioncs V&t&+<br />

cum in fk mutuo, perpekuo movebuntur de Iocis &is, titi, in<br />

~Corollario iuperiore expdfieum efi j neque cerrani quamvis inter fe<br />

‘\ gofitionem


RJ~NXPIA MATEHwATIcA.<br />

~%vol, 8. Si vas, fluidum inclufilm 8-z globus ~~VCIIC IWIC ~310..<br />

turn, & n~otu praztcrca communi angularl circa axcm quemvis datx.3rn<br />

revolvxn tur; quoniam hoc motu nova non mutatur attrirus<br />

pareium fauidi in fc invicem 9 non mutabuntur motus partium inter<br />

i-i?. Narn tranilationcs partium inter k pendent ab atcritu;<br />

Pars qwlibet in eo erkverabit moth quo fit Lit atwirL eX WJlO<br />

latere non magis tar cr etur quam accekretur attritu ex aleero.<br />

Lbrol. 9+ Unde fi vas quicfcat ac detur motus globi, dabitur<br />

rnotus fluidi. Nam concipc planum tranfire per axem globi &<br />

mocu contrario revolvi; & pone fiimmam tcmporis revolutionis<br />

hujus & revolutionis glpbi efG ad tempus revolutionis globi, ut:<br />

quadratunr kmldiametrr vafis ad quadraturn femidiamccri globi :<br />

& temyora periodic~a par&m fluid1 rcfpe&u phi ~hujus, erunt LIP<br />

quadrata difiandarum fiwrum ;i ccntro gIobi.<br />

GwaZ, IO. Proi,nde fi vas vel circa axem euradem cum glo,bo, vcl<br />

circa diverfurm aliqucm, data cum vclocitate quacunque movca..<br />

turJ dabitur nlotus A uidi. Nam i’i Syfiemati toti aukrartlr vnfis<br />

motus angularis, mancbunt motus omnes iidem inter k qui priusll<br />

per .Corol, 8. Et motus illi per Corul. 7. dabuntur.<br />

CuroX IX. Si vas & fluidurn quicfcant & globus uniformi cum<br />

motu rcvolvatur, propagabitur motus paulatim per Auidum tocum<br />

in vasJ & circumagerur vas nifi violenter detentum, neque prius<br />

definent fluidurn & vas accelwari, quam fint eorurn tcmpora pcrilodica<br />

azqualia remporibus periodicis globi. Qod fi vas vi aliqua<br />

detineatur vel revolva~r motu quovis conitanti & uniformi, deveniet<br />

A4edium paulatim ad fiaturn motus in,Corollnriis 8. 9 k IO.<br />

definiti, nw in alio unquam .fiatu quocunque pcricvcrnbit. Dcindc<br />

!vvcro fi, kribus illrs cefk~tibus quibus was & globus ce,rtis<br />

motibus


$1 llis omnibus ~uppono fluidum ex materia ~uoac? dedkatem<br />

& fluidiratem uniformi co&are. Tale efi in CJUO globus idem<br />

CodeIn CUIII mow, in eodem temporis intervallo> motus fimiles &<br />

;rquales, ad zquales kmper a k difhriass ubivis in fluid0 confiitutus,<br />

propagare p&it. Conacur quidem materia per motum<br />

&urn circularem recedere ab axe Vorti& & propterea premit<br />

marcriam omnem uireriorem. _Ex hat prefione fit attritus partitjlll<br />

forrior 8~ kpamtio ab invicem difficilior; & per conkquens<br />

chinuitur materiz fluiditas. Ruriirs ii partes fluidi funt alicubt<br />

craffiores ku majores, Uuiditas ibi minor erit, ob pauciorets fuper-’<br />

ficies in quihus partes feparencur ab invicem. %n hujufmodi cab<br />

bus deficientem fluiditatem vel lubricitate partium vel lentorealiave<br />

&qua conditione*refiitui hppono. ‘Hoc nifi fiat,, mat&a ubi<br />

minus ff uida et! magis cohrebit 8~ fkgnior hit, adeoyue motum<br />

tardius recipiet & longius propagabic quam pro ratione hperius<br />

afignata. Si figura vafis non !it Sphkrica, movebuntur particula<br />

111 lineis non circularibus fed conformibus eidem vafis figura, 8~<br />

tempera periodica ehnt ut quadrata mediocrium difiantizirurn &<br />

centro quamproxime. In partlbuo inter centrum 8;c circumferenham,<br />

ubi Xatiora fht fpatia, tardiorcs erunt mocus, ubi angufiiora<br />

velocioces , neque tamen particula velocirjres perent circumferenham.<br />

Arcus enim defcribent minus curves, 6z conatus recedendi<br />

3 centro non minus diminuetur per decrementum hujus, curvastura,<br />

quam augebitur per incrementum velocitatis. Pergendo a<br />

fpatiis angufiioribus in Jatiora recedent’ paulq longius a centro,<br />

fed ifio receffu tardefcent; & accedendo poflea de latioribus ad<br />

anguitiora accelerabuntur, .& fit per lvices tardefient & accelerab.untur<br />

particula: finguk in perpctuum. Hzc ita k habebunt in<br />

vak rigido, Pdwll in fluid0 inhito confiitutio Vorticum innote-<br />

1 kit per Propofitionis hujus Corollarium kxtum.<br />

Proprietaces autem Vorticuin hat Propohione invefiigare conatus<br />

fum, ut pertentarem @qua ratione ]PIiznomena coUIia per<br />

orti-


A EMATIC<br />

3J’f<br />

ortices explicari pofht. Nam Fhanomenon eit, quad Planeta- 131 n E rf<br />

rum circa jovem revolventium tempora periodica funr in ratione SEC “Ii Rvi’<br />

&$Quiplicata difiantiarum a centro Jovis; & eadem Regula obtinet<br />

jn Plan&s qui circa Solem revolvuntur. Obtinent autem h2t:<br />

Reguke in Planetis utrifque quam accuratiffime, quatenus obkrvationes<br />

Afironomica: haaenus prodidere. ldeoque ii Planet%<br />

illi zi Vorh&us circa Jovcm St Solem revolventibus deferantur,<br />

debebullt &am hi Vortices eadem lege revolvi. Verum tempera<br />

periodica partium Vorticis prodierunt in ratione duplicata d&ntiarum<br />

a centro motus: neque potefi ratio illa diminui & ad rationem<br />

fkfquiplicatam rcduci, nifi vel materia Vorticis eo fluidior<br />

fit quo longius difiat a centro , vel refifientia, quaz oritur ix defe&u<br />

lubricitatis partium fluidi) ex au&a velocitate qua partes<br />

fluidi ieparantur ab invicem, augeatur in majori ratione quam ea<br />

el? in qua velocitas augetur. Q uorum tamen neu trum rationi<br />

conientaneum videtur. Partes crafliores & minus’ fluidz.(nifi graves<br />

fint in centrum) circumferentiam perent; 82 verlfimile efi<br />

quod, etiamfi Demonfirationum gratia Hypothefin ralem initio<br />

SeCt.ionis hujus propofiuerim ut Refiltentia velocitati proportionalis<br />

efit, tamen Refiitentia in minori fit ratione quam ea velocitatis<br />

efi. Q, uo conceffo, tempera periodica partium Vorticis erunr<br />

in majori quam duplicata ratione difiantiarum ab ipfius centro.<br />

Qod ii Vortices (uti aliquorum efi opinio) celerius moveantur<br />

prope centrum, dein tardius ufque ad certum limitem, turn denuo<br />

celerius juxta circumferentiam j certe net ratio Mquiplicata neque<br />

alia quavis certa ac determinata obtinere potefi. Viderint itaque<br />

Philofophi quo pa&o Phaenomenon iilud rationis Ccfquiplicatx per<br />

Vortices explicari poflk<br />

P,oPosITIO LIII. THEOREMA XLI.<br />

Nam ii Vorticis pars aliqua exigua, cujus p.articulaz feu pun&a<br />

pkryfica datum krvant fiturn inter fe, congelarr rupponatur : haze,<br />

qaoniam neque quoad denfitatem filam, neqwe quoad vim infitam<br />

aut figuram ham mutatur, movebitur eadem lege ac prius: 8~<br />

%z contra,


II E h’l OTIJ contra, fi Vorticis pars congelata & folida ejufdem ik denfitatis .<br />

cortp ORuh4 cum reliquo Vortice, & rerolvatur in Auidum ; movebitur haec eaden1<br />

legc ac pius, niii quatenus ipfius parriculg jam Aaidz fa&g<br />

moveantur inter k Negligatur igfrur motus parricularum inrw<br />

fe, tanquam ad totius motunr progreflivum nil.fpeRams, 8r motus.<br />

fotius idem erit ac prius. Mtitus autem idem erit cum motu ah<br />

rum B/orticis partium a cefltro lrsqualiter difianrium, propte$e$,<br />

quad [olidwn in Fluidum refolutum fir pars Vorticis cazteris parribus<br />

confimilis. Ergo fblidum, fi fit ejufdem denfitatis cum mareria<br />

Vorticis, eodem motu cum ipfius partibus movebirw in mater.ia<br />

proxitne ambknEe relative, q~hdk~s. Sin denGus. fit, jam<br />

magis comiabitur recedere 2 centro ‘$rortisis8 quam prius; adeoque,<br />

Vorticis vim illam, qua prius in Orbita fuua tanqu,am in azquilibrio.<br />

condl-~turum retinebattir, jam hperans, receder a centro & rwol;<br />

vendo defcribet Spiralem ., non amplius in cundcm Ohem rediens,<br />

Et eodem argumenro pi rarius fit, accedct ad centrum. Jgitur Nan<br />

redibit in eundem Chbeln nifi fit e)..~fdem d;enfitati,s cum fluido.,<br />

Eo aurem in cafu oftenhm efi, quod revolvehztur eadem lege’cum<br />

pnrtibus Auidi a centro Vorticis xqualiter difiantibus. ,$2& E. 53.<br />

CO&, 1. Ergs folidum quad in Vorrice revoIvitur & in eund-em<br />

O&III kmper reditb relative quiekit in flu:idIo cui innatac.<br />

Carol. 2, Et fi Vortex iit quoad cle~4kArem wGfok%n.& co~$us<br />

.ide.m ad quamlibet a centro Vorticis difiantiam revolvi potcfi.<br />

Nine Iiquet Planetas 3 Vorticibus corpoks non &F&G. N?wI~~<br />

Planetx fecundum Hypothefin Coperlzic~anz circa Solem delati re*<br />

volvuntw in E,llipfibu$ uti,bilicum hbentibuh iia S,ole, 8~ radiis ad<br />

Solem d&is areas defcribunt remporibus proportion&s. At partcs<br />

Vorticis tali mowrcvo~yi nequc’unt, Defi.gm3~~~t AD, BE,C+F,<br />

O~bes trek circa S’olem S dekriptosy q\rorum extimus cir;’ circul’us<br />

dil~$b;li com32ntri;Cus; S;: iilter~orutil du4rtiti ApWia ht ‘4, B SE:<br />

Periheha 92, $3. Erg@ c&pw, qkd~revcsdvikur ‘in O&e :G F, rzdio<br />

ad Solem du&o areas temporibus proporrionales dcfcribendo, movcbitur<br />

uniformi cum mow. C~c,puS aute,m qaod revolvitur rin<br />

-&be BE’, tardius, movebitw .in Aplielio B Sr; VekXiiJS in. Peri-<br />

Jaelio, E, iecurldum kges Afkonomicas j cum tamen. fecundurn tee;-<br />

gcs h4ecbaaicas materia VoWicis in @ati allgufiiore inlter.,A& G<br />

velocius


15P<br />

d&eat qunm in atio Intiore inter 72 8-z F; id 1, i I: 1’1)<br />

efi, in Aphelia velocius quam in erihelio. C&p duo repugnant ’ F.r”“i ”’ CL<br />

inter fe. Sic in principio Signi<br />

Virginis, ubi Aphelium Martis<br />

jam verfatury drhncia inrer 01’~<br />

bes Martis & Vcsnep’is efi ad .$ifiantiam<br />

j&orundem’ .orbium in<br />

principio Signi PAium ut tria<br />

:ad duo circiter, & propterea<br />

r32hteria Vorricis ‘$nter 0-h ilh<br />

40s in *principio Piicium d&et x<br />

effe velocior quam in principio<br />

Virginis in ratione trium ad duo.<br />

Nam quo anguSus efc ipatium<br />

per quod eadem. Materia quan-<br />

71Ggas ,~eddekn -,revQlutionis unius<br />

4zempore ,4xanfit 9 ,eo majori cum<br />

yehpitate ,@ranfire ,debet. Igitur ii 4Yerrn in hat Materia cceleo<br />

fi; r&e&e quickens ab ea dektrecur,, & una circa Solem ire-<br />

:“volaeretur, foret .hujus velocitas in principio Pifcium ad ejutdem<br />

~&oeftat33n #irk 7pri&ipio Virginis ‘in racione fkQuialce.ra. ~Ulltb2<br />

Solis ,motas .diurrius apparens in yincipio ‘Virginis xn~jor ! efit<br />

qy~m minutorum :primorum tiptuagintas ‘& Gn princiyio<br />

tihor quam minutorum quadraginta & o&o: cum tamsn<br />

,4e.gtia z t&e) apparens ifie Salk motus major fit in print<br />

S&~ium. quart in .principio Virginis! &pFopterea Terra velo<br />

m cipio SUginis ‘quam in pninoipio Plfcium. Itaque Hypothefis<br />

rticain cum: Plxew3menis Afironomicis omnino pugnat, & non<br />

tarn ad explioandos quam ad perturbandos motus ccclefks conqjuci,t.<br />

.C&omodo vero motus ifii in iis libcris abdquc ortis<br />

peraguntxlr intelligi undi<br />

emate pknius doaebitur.<br />


Pg Libris pracedentibus principia Philofophia tradidi, non tamen<br />

Philofoph a fed Mathematics tanturn, ex quibus vi&-<br />

licec in rebus hilofophicis difputari pofl’it. k?ax fiint mow<br />

tuum & \Pirium leges & conditiones, qu3: ad Philofophiam maxime<br />

fpe&ant. Eadem tamen ,’ ne ficrilia videantur , illufEravi<br />

Scholiis quibufdam Philofophicis 9 ea w&tans qua generalia Cum,.<br />

& in quibus Philofophia maxime fundari videtur, uti corporum<br />

deniitatem & refiltentiam, fpatia corporibus vacua, motumque<br />

L&s or: Sonorum. SupereR ut ex iifdem principiis doceamus confiitutionem<br />

Syitematis Mundani. De hoc argument0 compofue-,<br />

ram Librum tertium methodo populari, ut a pluribus Iegeretur,<br />

Sed quibus <strong>Principia</strong> pofita fatis intelleaa non fuerint, ii vim confequenciarum<br />

minime percipient, neque prazjudicia deponent quibus<br />

a multis retro annis infueverunt: & propterea ne res in difputationes<br />

trahatur, fummam libri illius tranfiuli in Propofitiones,<br />

more Mathematico, ut ab iis folis legantur qui <strong>Principia</strong> prius<br />

evolverin t. Veruntamen quoniam Propofitiones ibi quam plurimaz<br />

occurranr, qua: Le&oribus etiam Mathematice do&is moram<br />

nimiam injicere pofint, author effe nolo ut quifquam eas omnes<br />

evolvat 5 fuffecerit fiquis Definitiones, Leges motuum & fk95ones.<br />

tres prior-es Libri primi kdu-lo legar, dein tranfeat ad hunt Li-.<br />

brum de Mundi Syfiemate, & reliquas Librorum priorum Propo,<br />

Gtiones hit citatas pro’ lubitu confulat.


Bcunt utique Philofophi : Natura nihil agit frufira, & frufira<br />

fit per plura quod fieri potefi per pxuciora, Natura onim<br />

x ef3 & reruin caufis fuperfluis noii luxuriat.<br />

Uti refpirationis in Hbmiite & in BkfIia j dkfdenfus )nJkJuu~ in<br />

JQf-opd & ill America j Lucis in Igne culinari & in SoIc; r&xionis<br />

~ucis inTerra & in Hanetis,<br />

R E G U L k’b III.<br />

Nam qyalitates corporum non nifi per cxperimcn ta innotcll;: tllltz<br />

igkoque. gencrales fiacuenda hunt cpocquot cum cxpcrimcrltiy KCniraliter<br />

quadrant ; 8t: quti minui non poirunt, non poftii~lc ju-<br />

FYrri. Gerte contra cxpcrimentorum tenorcm fomnia tcmcre confing~nda,<br />

~9x1. funt, ncc a Narurx analogia rcccdcndum CR, CLIP<br />

ca


i?r AI,xI?l ij fimplex ~0% foIeat SC dibi femper confona- Extenfio corporum<br />

Sai~cblATE~,~~ nifi per i&fus jnnotei‘cit, 1lfX in omnibus kntitur: Ted quia<br />

hfibillbus omnibus compew dc univerfis tiflirmarur, Corpora<br />

phi2 dufa eik experimur. 0ritur autem durities COtius a duritic<br />

pareium, & jnJe ‘no11 horum tailCuti> corporum HUE ientiufitiur,<br />

ibd aliorum etiam on$liilm particulas indiviks &Ye du’ras mePito<br />

concludimus. corpora omnia impenerrabilia eG2 flOn ratione fid<br />

fi2nfu ct)Iligimus. (&IX ‘ttw.%mus, impenetrabilia ifiveniuntur, &<br />

illde conc]udimus impenecrabilitatenl efi proprieratem corporum<br />

univerforum. Corpora omnia mobilia effe, Se viribus quibufdam<br />

(qllcls vires inert& vocamus) perfkverare in motu vel quiete, ex<br />

17 j& corporum viforum ,prdprietaeibus cdlliginik7. ‘EWcrifr‘o, ‘dtiritles,<br />

impei~etrabiliras , mobilitas & vis inerdz totins, mitur ab<br />

exrenfione, durltie, impenetrabilitate, mobilitate & viribus inert!:.<br />

partiurn : & inde concludimils omnes bmnium corporum par...<br />

tes minimis exrendi & duras effk & impenetrabiles St mob2esi :&<br />

viribus inerr& prxditas. Et hoc efi ,fundamentum Philofophiae<br />

to tius. Porro corporum partes diviIas Csr fibi mutuo contiguas ab<br />

jnvicem kparari pofi, exPhznomenis novimus, & partes indiv&s<br />

in partes minores ratione didtingui poffe ex Mathematics<br />

certum efi. Utrum vero “parces illcl: difiinQx & \nondum divi&<br />

-per vifes’Natka.z &vidi ik ab invicem kparari pofint, i&+&m<br />

efi. At G vel unico confiaret experiment0 quod particdktiliqua<br />

indivif& frangendo corpus durum QT: iblidum, divifionem patere-<br />

.k..r : concluderetius vi hhjus Regulx, quod ncjh *folum partes di..<br />

-vik ,feparabiles &l&t, fed etiam ,quod indiGtk in infinitum dividi<br />

pofli3 t.<br />

Denique fi corpora omnia in circuitu Terrs gravia effe inTerram,<br />

idque pro quantitate mater& in fingtilis, & Lunam gravem<br />

effe in Terram pro quantitate maceriz fux, & vicifim mare no..<br />

firum grave eKe,in Lunam, .& PI&eta! omnes..-&raves,tiffe in .;Te<br />

mutuo, 8a Comctarum fimilem effe gravitatem, per experimenta<br />

& obfervationes Afkonomicas univerfiliter co&et: $cerk!um Grit<br />

per ,hanc ,Regdlam gytid corpcra otinia in Sk mhtuo’” grti$itant.<br />

Nam & fortius erit argumenturn ex Phlenomenis de :gravitate uni..<br />

bei-fali, qtiaui de ‘corporum in,ipeneti%bilirace: ‘de. qua utkitie in<br />

corpo~ibus Coe’leftibus nullum expf3inientUn3 nulkim prorfis “i+kriadonem<br />

’ ha’b6mus.


Id. z*$!‘, zy’, 34”. 3!, 13~. x3’. 42”. 7”‘. 3? L&z ! 36”. ~6”. 1 (jr’. 32’. y”,<br />

1.1 II r. R<br />

‘I’ I’ I, ‘1’1 u s.


hlercurium & Venerem circa Solem revolvi ex eorum phafibus<br />

lunaribus demonfiratur. Plena facie lucentes ultra Sol&m fiti funt><br />

dimidiata 2 regione Solis, fhata cis Solem j p&r difcum .ejus ad<br />

modum macularurn nonnunquarn trankuntes. Ex Martis quoque<br />

plena fkie propc Solis conjun&ionem, & gibbofa in quadracuris,<br />

certum efi quad is Solem ambit. De Jove etiam & Saturno idem<br />

ex eorum phafibus kmper plenis demonfiratur,<br />

l?H&NQMENQN<br />

IV.<br />

~dnetdrum qwinque primariorum, & (cuel Solis circa Terrdm 5x1)<br />

Terrle circa Solem rempow periodicu e[e ilz ratione fe$qu@&<br />

~~td mediocrium di/h&wum ~2 Sole.<br />

HXC A I


De difiantiis Mercurii & Vencris n Sole difputandi IIOII cfl IOCLIS,<br />

cum haz per eorum Iongationcs 5~ Sole deccrmincntur. De difiantiis<br />

c&m fhperiorum Plaaetarum ci Sole tollicur 0mniS d+utatio<br />

per Eclipks Satellitum fovis. Erenim per Eclipks illas dcterminatur<br />

pofitio umbrg quam Jupiter projicir, Sr: eo nominc<br />

habetur Jovis longitude Heliocentrica. Ex longitudir~ibus aLltern<br />

Heliocentxica & Geocentrica inter fe collatis dctcrmhatur diitan -<br />

tia Jovis.<br />

PH,.iENOMENON V.<br />

.Phzetm prhzur~os, radiis ad Terrmn dz&is, mm defcriherc temporibm<br />

FPG&EW proportiondes j dt rddG8 ad Solem did&s, nrem<br />

tewporib~5 proportionules percwrcre.<br />

I<br />

Nam refpeQuTerrx: nunc progrediuntur, mrnc ftatioaarii f~rnr~<br />

nunc etiqm regrediuntur : At Solis rcfpe&u fernper progrediuntur,<br />

idque propemodum uniformi cum motu, fed paulo cclerius tamen<br />

in Periheliis ac tardius in Apheliis, fit ut arearum zquabih fit dcfiriptio.<br />

Propofitio kfi Aitronomis notifima, & in Jove npprimc<br />

demonfiratur per Eclipks Satellitum9 quibus Eclipfibus ldcliocentricas<br />

Planetzl: hujus longitudincs & difiantias li Sole dctcrminari<br />

diximus.<br />

atet ex Lunar motu apparentc cum ipfius diamcrro apparcntc<br />

collata. Perturbatur autem motus Lunaris aliquantultrm ;I vi Solis,<br />

kd errcxum infenfixbiles minutias in hifcc Phwomcnis q&gyw


DE MuNlJs<br />

SYSTEhlATE<br />

Atet pars prior Propofitionis p%r P~w~~m~~on- primL?m, &<br />

Propofitionem fecundarn vel tertiam Libra primi: ‘I$ ars<br />

pofieriar per Pha33.amenon primum, &: Corollarium fextuni f: row<br />

pofitionis quartz ejufdcm l,ibri.


Eitet affertionis pars prior per Phznomenon kxtum, & Propo-<br />

&Mitionem SeCUndam vel tertiam Libri primi : & pars pofterior<br />

+r .rncirtIht tardifimurn Lunaris ApogXi. Nam mows ilk, qui<br />

fingulis revol’utionibus eit graduum tantum trium & minurorum<br />

trium ia c0nfeqwentia, contemni poreit. Patet cnim (per Coral. 1.<br />

Prop.xLv. Lib. I.) quod fi difianria Lun3: a centro Terra: fit ad<br />

GZnidiametrum Terra ut D’ad I; vis a qua mocus talis oriatur iit<br />

iwiproce ut D z&~, id eft, reciproce ut ea ipfius D dignitas cujUs<br />

Index efi 22&, hoc e&in rarione d&antia: paulo majore quam<br />

d’uplicata inverie ,* i’ed qurr: partibus 59: propius ad duplicaram<br />

quam ad triplicatam accedit. Oritur vero ab a&iorie Solis (Ufi<br />

pofihac dicetur ) & propterea hit negligendus eit;. A&io Sobs<br />

quatenus Lunam difirahit a Terra, ef? UC difiantia LL~CEZ a Terra<br />

quamproxime j ideoque (per ea quz dicuncur in Coral. 2. Prop.<br />

XLV. Lib, F.) eit ad Lunar: vim centriperam ut z tid 3 ~,7,45 circi-<br />

6er, feu I ad 178$Z. Et negle&a Solis vi tantilla, vis reliqua qua<br />

una retinerur in Urbe erit reciproce ut D 2. I’d quod edam<br />

plenius confiabit conferendo hanc vim cum vi gravi.tatis; ut fk<br />

in ~~ropofieione fequente.<br />

GwuZ. Si vim centripeta mediocris qua Luna retinetur in Orbe,<br />

‘;augeatar pritio in ratione r77@ ad 178$$, deinde etiam in rati-<br />

;one duplkaca kmidiametri Terraz ad mediocrem d’ifiantiam centri<br />

Eunze a centro Terra : habebitur vis centripeta Lunaris ad hperficiem<br />

Terra , @ito quod vis illa dekendendo ad hperficiem<br />

Terra, perpetuo augeatur in reciproca altitudinis ratione du-<br />

$3licata.<br />

PR.OPOSIT’IO IV. TH-EOREMA IV.


DE h’f!JN~l<br />

~YSTEhIATEf~qU~~~~~r<br />

chne~ 56% Afi ~ycho, & quotquot ejus Tabulas refra&ionur~<br />

, confiituendo refrafliones Soils & Un;E (omnino con-<br />

Era nacllram Lucis) majores quam Fixarum, Jdque firupulis quasi<br />

quatuor vel quinquc, auxerunt paralla,xin Lunz fcrupulis tocidem,<br />

hoc eft, quafi duodecima vcl decima quinta parte totius parallaxeos.<br />

Corriga tur iite error, & diitantia evadet quail $02 kmi-<br />

&ametrorum terrekiiim, fere ut ab aliis afignatum ek Affimamus’<br />

difianti;am mediocrenz kxagints femidiametrorum 5 & Luna-<br />

rem periodurn refpeQu Fixarum cbmp!eri diebus 273 horis 7, r&<br />

nutis primis 43, ut ab Afironomis itatu;turj atque ambitum Terry<br />

ere pedum Parifienfium I 2324.3600, utr a Gallis menfurantibus defiraitum<br />

eit : Et G Luna motu omni privari fingatur ac dimitti ut,<br />

errgenre vi illa omni qua in Orbe f30 retinetur, defcend’ar in Terram<br />

j hzc fpatio minuti unius primi cadendo defcribet pedes Parilien&<br />

151% Colligitur hoc ex calculo vel per Propofitionem<br />

xxxvr. Eibri primi, vel (quad eodem recidit > per Corokium<br />

nonurn Propofitionis quartz ejufdem Libri, confe&o, Nan1 ar..<br />

cus illius quem Luna tempore minuti unius pr;imi, me&o f$o<br />

motll, ad diitantiam kxaginta fkmidiametrorum terrefirium de-<br />

fir&at, finus verCus efi pedum Parifienfium 15~~~ circitec. Wkde<br />

cum vis illa accedendo ad Terram augeatur in duplicata difiantia:<br />

ratione invcrfa, adeoque ad ~uperficiem Terra: major fit partihus<br />

60 x 60 quam ad -Lunam 3 corpus vi illa in regionibtts nofiris ~11..<br />

dendo, defcribere deberet fpatio minuti unius primi pedes Parifienfes<br />

60 X 60 % I 5;i, & ipatio minuti unius fecundi pedes x 5h.<br />

A tqui corpora in regionibws nofkis vi gravitaris cadendo, defcribunt<br />

tempore minuti unius fecundi pedes Parifienks 15132, uti<br />

Huge&w fa&is pendulorum experimentis & computo inde inito,<br />

demonfiravit : Sr propterea (per Reg. r. 6t Ix.) vis qua Luna in<br />

Qrbe $uo ret&cur, illa ipfa el% quam nds Gravitatem dicere fo]e-<br />

J~IUS. Nam ii Gravitas ab ea diverfa efi, corpora vEribus utrifqtie<br />

conjun&is Terram petendo, duplo veIocius dekendent, & fpatio<br />

sninuti unius kcundi cadendo defcribenr pedes Parifien& 30% :<br />

omnino contra Experientiam.<br />

Calculus hid fundatur in hypotheh quod Terra’qukfcit. &Jam<br />

G Terra & Lun;) circum ,Solekn moveantur, & inter,ea q,uoque cir*<br />

cum cammune gravitatis centrum revolvantwr : , diltantia centrorum<br />

Lunx: ac Terra ab invicem erit 60; femidiametroruti ter-<br />

I:efirium j. uti conhputationkm (per Prop. IX, Lib. 1. ) ineunti<br />

gwzebitk ,.<br />

&,‘&


Nam revoluriones Phnetarum Circumjovialium circaJovem, Cir-<br />

6Xlmiaturniorum circa’ Saturnum, Sr Mcrcurii ac Vencris rcliquorumque<br />

CircumfT3larium circa Solem iimt Phanomena ejufdcm gcneris.<br />

cum revo~luciplle LulXC circa Terram j & propceren per<br />

Reg. IL ci caufis ejufdem geqeris dependeut : yrskrth cum demonftratum<br />

fit quod vires, h quibus rcvo1thonc.s ilh depcndem,<br />

ref’iciant centra jovis, Saturni ac Solis, & reccdendo ri Jove, Sam<br />

tur’t~o & Sole decrefiant eadem ratione ac kge, qua vis gravitatis<br />

decrefcit in recef5.u A Terra.<br />

fZk~vo,f,. I.. Gravitas igitur datur in Planetas univerfos, Nam Vcnercm,<br />

M&curium, czterofque effe corpora cjufdcm gcncris cum<br />

Jove 6t Sarurno, nemo dubitac. Et cum attraCti omnis (per mo-<br />

$1~23 Legem tertiam) mutua fit 9 Jupiter in Satellires files omncs;<br />

Saturnus in Cues, Terraque in. Lunam, & Sol in Planetas omnes<br />

primaries gravitabit.<br />

CuraL 2. Gravittitem,’ quz Planetam unumquemque rerpicit, efc<br />

reciproce ,ut quadraturn diftantiaz locorum ab ipfius centro.<br />

curot; . Graves fine Planets omnes in fe mutuo per Coroll. I.<br />

& 2. Et .f? inc Jupiter & Saturnus prope conjurkkioncm k irzviccm<br />

attrahendo, hfibiliter perturbant motus mucuos, Sol perturbat<br />

nlotus kunares, Sol & Euna perturbalIt Mare nofirum 3 UC in<br />

fiquentibus explic,abit.ur.<br />

P.R.OPOS1’J?IO VI. THEOREM~A VI.


v<br />

1) I( ~1 UN ,, I remporibus fieri, jamdudum obkrvarunt alii 5 6c: accuratifime qui-<br />

~IS’~~A~~~TE dem notare licet aqualitatem temporum in Pendulis. ,Rem ,tentavi.<br />

in Aura, Argento, Plumbo, Vitro, Arena, Sale communi, Ligno,<br />

Aqua, Tritico. Comparabam pyxides duas ligneas rotukdas &<br />

squales. Unam implebam Ligno ) & idem Auri pondus Mjpendeban2<br />

(quam potui exaAe) in alferius centro ol’cillationis;<br />

ab ;~qu~libus pedum undecim filis pendentes, confiitueb<br />

dul;l? quoad pondusJ figuram, & aeris refifientiam omnin’o pal;ia:<br />

EC paribus &illationibus> juxta.pofita, ibant una Sr redibant dintiflime,<br />

Proinde copia materiae 111 Auro (per Coral. I. & 6. Prop.<br />

~:XIV. %ib. II.) erat ad copiam mater& in Ligno, ut vis motricis<br />

a&io in totum Aurum ad ejuii;lem aaionem in totum Lignutn ; h”oc<br />

e[t, UC pondus ad pondus. ,Et & in catteris. In corporibus ejuf_<br />

dem ponderis diA-‘erenria materk, quaz vel minor e&t quam pars<br />

nlillefima mater& rorius, Isis experimentis m!anifefIo deprehendii<br />

potuit, jam vero naturam gravitatis in g!,netas, eandem effe atque<br />

in Terrnm, non efi dubium. Elevari e,fIlm fingantw co,rpwa kc<br />

Terreflria ad ufque Orbem Eunx, & una cum Lwna mptu omni<br />

privata demitti, UC inTerram fimul cadant; & per jam ante offenfa<br />

certum efi quod temporibus zqualibus dekribent aqualia Qatia<br />

cum Luna, adeoque quod fint ad quantitarem mater&z in Luna, ue<br />

pondera Lila, ad ipfius pondus. Porro quoniam Satellites Jovis<br />

temporibus revoIvuntur qutc runt in ratione kfquiplicata ‘ditiantiarum<br />

a ceilltroJovis, erunt eorum gravitates acceleratrices in Joi<br />

vem reciproce u.t guadraca difiantiarum j centro Jovis; & propterea<br />

in zqualibus a Jove difiantiis, eorum gravitates, acceleratsices-<br />

,evaderen,t aequales. Proinde temporibus zequal’ibus. ab ;EqualPbus<br />

altitudinibus cadendo,. defcriberent xqualia @atia j perintie ut.‘: f;itr<br />

in gravIbuqF in hat Terra kfira. Et eodem argument0 PknetaE1<br />

circkmfolares ab aqualibus 3 Sole difiantiis demif?i, dekeni”u ,610<br />

in Solem equalibus temporibus aqualia fpatia deIk+berent, Kres<br />

autem, quibns corpora inzequalia zqualiter accelerantur, Eunt, ut<br />

corpora j hoc efi, pondera ut quantitates mate& ia Plane&.<br />

!?ONQ Jovis & ejus Satellitum po!ldera in Sole proportionalia<br />

,efFz quantitatibw materk e.orumy p!ate,t .ex motu W4iWm qua02<br />

maxi&o regd]aG ; per Coral, 3:. Prop, LSV, L Nasm, ii horum<br />

aliqwi magis- W&erentur in S.olem, pro Qv&tit,ate mater&<br />

fu33 quam ckteri : motus Satellitum, ( per Coral, 2.‘ Prop. ILXV,<br />

Lib. 1.) ex iazqklitare attrafiionik per8u&aw$&.ur. Si (pw&us<br />

2 Sole difiantiis~ Sat&es aliquis. graviQr &Get ia So@m pxo. QW~~<br />

tirate


titate mater& f&E, quam Jupiter pro cpantifxte mareriz fw, in<br />

ratione quacunque data, puca d ad e: diltantia inter centrum So- ~k~:t’;:,.<br />

lis & CXntrum Orbis Satellitis, major femper foret quam diltantia<br />

inter centrum Solis & centru.m Jovis in racione hbduplicara quam<br />

proxime 5 uti cal~~lis quibufdam inicis inveni. Et fi Sacelles minus<br />

gravis cn”et in Solem in rationc illa d ad P, difiantia centri<br />

Orbis SacellitGs a SoIc rt~inor foret quam diftantia’centriJovis ;j<br />

Sole in racione illa iubduplicata. lgitur fi in squalibus 3 Sole<br />

diltaneiis, gradaS accelerat$x Satelhtis cujufvis in Solcm major<br />

cflkr’ +el minor grlam ,gravlcas accelerarrix Jovis in Solem, parce<br />

ta~~tum ‘millefima grawratis -torius 5 foret difiantia cencri Orbis<br />

Sarellitis A Sole major. vel minor quam difiantia Jovis ,i Sole<br />

P=Erte Go di&antiz torius, id eit, parte quinta dihncix Satellicis<br />

extinii A centro Jovis : C&x quidem Orbis eccentricicas fore valde<br />

fcnfibilis. Sed Orbes Satellitum fint Jovi concentrici, & propterr=a<br />

gravitates accekratrices jayis & Sa.tellitum in Solem axy2azntur<br />

S&~rer’ {‘CL Et eadem aSgumenco pondera Saturni isI: Comitum cjus<br />

irl Solem, in tXq u&bus . A Sole diftantiisJ fhnc ut quantitates mntc-<br />

Xi,% ii-i ipas : Et pen&-a Luna: ac Terra: in Solem vel nulla iiu~t,<br />

we1 e.arua l&Q wCurate proportionalia. Aliqua autem h-~t per<br />

orsl. I., & 3. Prbp. v.<br />

Q&&km pondera garrium GqyEasum Bl~net~~ cu~ufque~ in<br />

i+.iwm quemcu#qw$ C&E, inter fc uE, materia 6n pwi5b.w fiilgulfis.<br />

Nam ii partes a!ique plus g,ravPfkXent, diamim~s, quam pro C$UaLl-<br />

-- difare materk: Planeta totUS, pro genere partium quibus maxime<br />

,*bag&tj gpa&&t: mngis, v& minw quam pra quantitatc materi<br />

.&wiw. $d q~c..&?gyr. wLtrun3 par&f3 iEh externs fii3.t vel Bnternz<br />

.N%m, fi ver-b.i .graria c.orposa Tew2Oria, qua2 spud nos hnt, in<br />

Orbem Lund elevari fingantur,& conferanrur cum corporc kunce:<br />

Si horum pondera erent ad pondera partium externarum LUIU<br />

I.I& quantirates materia in iifdem, aid po-ndcra vero phrtium internarm<br />

in majai ael .minosi rarione, forent eadem ad pondus<br />

nz torius in. m,aj.oai *vvd: mimor5 ratione :. contra quam hpra<br />

fidilm efl?. .<br />

_ cmei f. inc pmw&im ~orporum non pedenr ab eorum foris<br />

& l~XCU.r~S. Ham fi cum Forn$: variari POfilIt j FOlWlt ma--<br />

ra vel minora, pro varietate formaturn,. i.n aquali~ maWia: OllTnmp<br />

corma Experientiam.<br />

I . :<br />

G?r0Z.


I<br />

r> F i\ I u F! n I<br />

I;,‘STEMATE .<br />

CO&. 2, Corpora univerfa quz circa Terram func, gravia funt<br />

m Terrain ; & .pondera omnium, qulr: azqualiter A centro Terra<br />

diitant, funt ut quantitates materiz in iifdern. I~[zc efi qualitas<br />

omnium in quibus experimenta infiituere hcet, 8r propterea per<br />

Reg. I rr. de univerfis affirmanda efi. Si Ather aut corpus aliud<br />

quodcunque vel gravitate omnino deititueretur, vel pro quantitate<br />

mater& f~m minus gravitaret : quoniam id (ex mente Arz~atelis,<br />

c&rteJ’ & aiiorum) non differt ab ahis corporibus. niG in forma<br />

materix, pofit idem per mutationem forma gradatrm tranfmutari<br />

in corpus ejukfem conditionis cum iis qua2, pro quantitate mater&<br />

.quam maxime gravitant, & viciffrm corpora maxime gravia, fornlam<br />

illius gradatim induendo, pofint gravitatem ham gradatim<br />

amitcere. AC proinde pondera penderent B formis corporum,<br />

poirentque cum formis variari, contra quam probatum eR in<br />

lrCorollari0 fuperiore.<br />

CoroL 3, Spatia omnia non Gnt zqualiter plena. Nam ii fpatia<br />

cmnia aqualiter plena effent, gravitas fpecifica Auidi quo regio<br />

acris impleretur, ob fummam denfitatem mater& nil cederet gravitati<br />

fpecifica: argenti vivi, vel auri, vel corporis alterius cujuC<br />

cunque deniifimi ; & propterea net aurum neque aliud quodcunque<br />

corpus in aere defcendere poiret. Nam corpora in fluidis,<br />

nifi fpecifice graviora fint 3 minime dekendunt. Qyod *ii<br />

.quantitas mater& in fpatio dato per rarefaeionem quamcunque<br />

.diminui pofit, quidni diminui pofit in infinitum?<br />

Coral. 4. Si omnes omnium corporum particulze folidz fint ejuf-.<br />

dem deniitatis, neque abfque poris rarefieri pofint, Vacuum da-<br />

:tur, Ejufdem denfitatis effe dice, quarum vires inertia: funt ut<br />

.magnitudines.<br />

&rod. f,:’ Vis gravitatis diverfi efi generis a vi magnetica. Nam<br />

.attra&io magnetica non eR ut materra attra&a. Corpora aliqua<br />

anagis trahuntur, alia minus, plurima non trahuntur. Et vis magnetica<br />

in uno & eodem corpore intendi pot& & remitti, eftque<br />

nonnunquam longe major pro quantitate materia quam vi3 gravitatis,<br />

& in receffu a Magnete decrekit in ratione difiantize non<br />

duplicata, kd fere triplicata, quantum ex crairas quibufdam c&&r==,<br />

sationibus animadvertere potui.


Planetas omnes in fi mutuo graves effr jam ante probavimus,<br />

ut & gravitatem in unumyuemquc korfim fpetiatum effe reciproce<br />

ut quadratum difiantilr: locorum A centro Planetaz. Et indc<br />

confkquens eft, (per Prop. Lxrx. Lib. 1. & ejus Corollaria ) gravitatem<br />

in omnes proporeionalcm efk matcrix in iii&m.<br />

orro cum Platletlr: cujufvis A partes omnes graves ht in PLI.~<br />

netam quemvis B, & gravitas partis cuju$ue fit ad gravitatem<br />

totiws, ut materia partis ad maceriam totius, I& a&ioni omni rea&i0<br />

(per motus Legem tertiam) aqualis fit ; Planeta B in partcs<br />

omnes Planeraz A vicifflm gravitabit, & erit gravitas filla in partern<br />

unamquamque ad gravitatem Guam in totum, ut materia partis<br />

ad materiam totius. g&E. “23.<br />

Curoll 3. Oritur igitur & componitur gravitas in Planetam tocum<br />

cx gravitate in partes fingulas. Cujus rei exempla habcmus<br />

in attra&ionibus Magneticis & Ele&ricis. Qritur enim attra&io<br />

omnis in totum ex attra&ionibus in partes fingulas. Res intelligetur<br />

in gravitate, concipiendo Planctas plures minores in unum<br />

Globum coire & Planetam majorem componere. Nam vis totius<br />

ex viribus partium componentium oriri debebk Siquis o bj iciat<br />

quad corpora onuk quaz apud nos funt, hat lege gravitare dcbere.nt<br />

in fe mutuo, cum tamen cjufmodi gravitas neutiquam fin-.<br />

tiatur : Refpondeo quod gravitas in hat corpora, cum fit ad grae<br />

vitatem in Terram totam ut Eirnt hat corpora ad Terram totam,<br />

lon,ge minor eft quam qu* kntiri pofit.<br />

GoroZ, 2. Gravitatio in fingulas corporis particulas zquales cfi<br />

rcciproce wt quadratum diftantix locorum 3. particulis. Patet: per,<br />

Coral. 3, Prop, LXXIV. Lib. J.<br />

bb<br />

B R cab


37”<br />

zs<br />

Pofiquam inircniffeti grAvit2tel-n in Planetam totuti oriri &<br />

oomponi ex gravitatibuS in partes: & eire in partes fing”u?as reciproce<br />

propoPtional& quadratis diff antiarum a patrlbus: d.ubitabarn<br />

an reciproca illa proportio driplicata obtineret accurate in vi<br />

tota ex viribus pluribus compofita, an vero quam proxm~e. Nam<br />

fieri poff~ ut proportio, qia’li: in majoribus difiantiis fatis accurate<br />

obtiaeret, prop6 filperf;iciem Pla~etz ob inkquales garticularr;tn<br />

dlflantias & fitus difimile& notabiliter err&ret. r’ande&<br />

veros per PWP. Lxxv. & rAxXv1. Libri @%Gi & ‘ipfilium ~~~&<br />

Iaria, inteki v&tat&h Propofitionis de qua hil: agitur.<br />

Coral. I. Hint inveniri QE inter Ce compk%ri pofint pondets<br />

.eorporum in diverfos Planetas. N am pondera corporum aequa-<br />

&urn circutn Ranefas in ti?Ciilis revolventihfi fuuht (per, For&. 2.<br />

pop, IV. Lib, 1.) tit diatiegti circulbtum did@:& ~‘LIA~CI& tttiportiti<br />

pe~iodiddi’L~m inveG 5 & pondeta ad fupes$ck3 Pianecaruti,<br />

ahaM quafvis a cdiitro difiantias, majora filnt TM mindta<br />

(per hzinc P’ ro p o ‘I- It&em) in duplicata: ratione ~diRant?aru~ &<br />

ge&, Sic ex temp&bu& periodic& Vkneris circus Solem @+.<br />

$fiim %i+ ‘si: horarum 14 $‘, Satellitis exiriiili Ciic,ti~thjoUi;ilis circu&<br />

J&.eti &fij&.<br />

i6 & hsrPi4ti 16 Ipi j SaMitis ,Hugefii& c&U&<br />

Stiturtii.crti &+um i 9 5% BMu4.m~ 2.2t1 ,& fitin& cfi'c'u'ff~ 'TWfarti<br />

dieruljl 27, hbk, 7. tii’ti. @; ~ollZiti$ Mn difiahtja Wed6bcri Ven&+:<br />

ris a Sblt & cuti elon@atloMW tiaximis hCl~Oc&$~?~~i~ Satellftis,.<br />

I extimi circumjovialis a cenrro Jovis 8’. i I:“, Satellftis E-lugen?gfif’<br />

a centro Saturni 3:. zo”, & Lunx a.Tcrra IO’, compu,tum ineundo.<br />

iti$+eRi qti&iil kbiijokQiI @~Miu’m & ‘A Sble, Jove, SaWrna ‘ac”r&ra.<br />

~~Wl~~& difiafitiwti ponder9 in Solem, Jovem, Satu)rnum acTeye<br />

ram fbrent ad invicem ut I, --& -+ ti 2-i. ~tfp”pei%vi-~ Eti eni&.<br />

parallaxis Solis ex ob fervationiGi novZX$& quafi JO”, 82 NUZ-<br />

&s fiofier per emerfiones Jovis & .Satellitum e parte obkura.<br />

Lunaz:o


371’<br />

4UQd elongatio maxima .heIiocentrica SJtcl[i- L I II<br />

entro Bovis in mediocri Jovis 3 Sole difian- TfFrruj.<br />

St ckmxter Jovis 41”. Ex duratione Eclip~em<br />

Satellitum ~~ ~~~bram jovis incidenciuln pro&t h,rc diameter<br />

q$a*fi 405 atque adeo C2midiamerer 20”. Meniizravit autem kh-<br />

$~&y3,~hjpPcio”cm maxim?m h&qcentricam Satellitis a fk de-.<br />

a CentrO SaturnI, 8r: hulus eIongatronis pars quarta,<br />

8-empe ro”, ef% c&meter annuli Saturni e Sole viii, & diameter Saawni<br />

‘efi ad diamerrum annuli ut 4 ad 9, ideoque i&ni&ameter<br />

Saturni e sole vifi efi II”. Subducatur 11.1x erratica qw haud<br />

minor effe l3iet quam 2” vel ~3” : Et manebit kmidiameter Saturni<br />

.quafi 9”. EX hike autein & Solis fkmidiametro mediocri 16’. 6”<br />

computum ineundo prodeunt veraz Solis, Jovis, Saturni ac Terrs<br />

femidiametri ad invicem ut I[OCOO~ 1.077, 889 & IO+ Unde,,<br />

turn pondera zqualium cocporunn a centris Solis, Jovis, Saturnr<br />

ac Terrae zqualiter difiantium, fint in Solem, Jovem, Saturnum<br />

z;Ic, Terram, ut I9 -?- 9 SIB 8c -A-- reipe&ive, & au&is vel dimixxutis<br />

difiaxxtiis ptA3dera dirni~~~~tur vel augeantur in duplicata<br />

ratione : pondera, squalium corporum in Solem, Jovem, Saturx3um<br />

ac ?k’erPam in difiantiis IOOOO~ x077, 889, & 104 ab eorum<br />

centris, .atqVe adeo in ewum fuperfkiebus, Grunt UC roosq, .83$$<br />

& 4x6 refpe&ive. manta fint,pondera cor.porum m *fu$erdicemus<br />

in iequentibus:<br />

2. lflnotefkit etiam quantitas mat+2 in Planetis fiqgL$is,<br />

ntitates materix in Planetis Cunt ut eorum v&es in gquaantiis<br />

ab .ecxum centris f) id c$j~~ in S.ole, Jove, Saturno ac<br />

erra funt xlt f, s3, z&9 8~ --?- refpetiive. Si parallaxis Solis<br />

22751%<br />

tuatur major vel minar quam IO”, debebit quantitas materia: in<br />

erra augeri veil dimhui in triplicata ratione.<br />

* coroz. .:3- l.qnstefc,ung Qiag-l den,fitates PXw3,etww gnaw pan--<br />

dera corporum zqual;urn SZ: homogeneorum in Sphzeras llomogefunt<br />

sm fiperficiebus Sphzt-arum ut Sphaerarum dlametri, per<br />

. LXXLI. jib, 1. ideoquc Sphaxarum heterogenearum den&<br />

:fUnc ut pondera illa applicata ad Spheraym djametros.<br />

,Eant,autem per= Solis, Jovis, Sarurni ac Terrae dlametrl ad lnvl-<br />

$3323 us: IO~u‘~s xqv3<br />

$89, st m4, & pondera in eofdem ut 1.ooo.0,<br />

& pqxgerea d,er+itwes funt pt ZOO, 78, WB<br />

.D.cnfitas ,Terrg .~LICFZ pro&it ,ex hoc co?pNo non pm&t<br />

So&is -$if .~&~er.minatW .pF ~pw%W: T-l.WEe3 .& I?q@P-<br />

Bbb .2 terea<br />

F R ‘-


Hwi MATHE 373<br />

IWlt. Eaque de caufa Globus terreus aquis undique cooperrus, L I 1P E R.<br />

fi rarior effet quam aqua, eirlefgaxX alicubi, tk aqua omnis in& TERTl.U~*<br />

ClCAWnS congregyrCXur in regione oppolita. Et par eit ratio<br />

Terrace notIr;l: rn:~r~bus magna cx parte circumdac:L Bl[;w fi &I+<br />

fior IL~OII efit, enlergcrct a mar&us, & parte fili pro gradu levitabs<br />

extarer cx Aqua3 nwribus omuibus in regionem oppofitam<br />

col1Anentrbus. Eudeln argumeuto mnculz Solarcs lcviores fiu&<br />

gusm IX:1tc;:ria luci+ Sohis cui. fiipernatanc. Et in forlnatione<br />

quallcUn~~ue PL~nccwXw , anateria omnis gravior , quo tcmporc<br />

maffa tota flu;& cfat? ccnrrum pet&at. Wade cyn Terra tommunis<br />

fiiprciria yu3ii du~lo gravlor fit quam ag:un, $C pauIo inferius<br />

in fodinis quafi triplu vel quadruple aut ct~;pm ~luintuplo gra-<br />

Vior repcriatur : yerihr~~k. CR quad copia materix tcttlus ill Terra<br />

juafi qlIintuplo vel ftxtup!o major fit quam ii CoCa cx aqua conaarct<br />

j pr:Ekr tin3 cum Terram quafi quinruplo denfiorwn cft&<br />

uam Jovem jam ante 0iPenfilm fit. lgiour ii Jupiter pad0 ch-<br />

? lot: fit quam aqua 3 hit rpatio dierum triginta, quibus long<br />

gitudinem 4~3 fimidiametrorum fuarum defcribic, aktterer irl<br />

M(edio.ejufdem denficaciu cum Acre nofiro motus fili parrem ferc<br />

&cimam.~*~ V’erum cum refilter&a Mediorum minuatur in ratione<br />

ponderis ac dcnfitatis, fit ut aqua> ‘qu;x: partibus 1st lcvior ~3%.<br />

quam; arptum vivmn, minus refifiat in eadern ratione; & acr,<br />

qui partibus 8fo’ levior efi quam aqua, minus refifiat in cadem,<br />

Aone : fi afcendatur in coelosi ubi pondus Mcdiitl in quo Planet~~<br />

gnoventur, diminuitur in immeqfum, refifientia propc cc&W. :<br />

iixpltwr.<br />

ROPOSTTIO XI. TMEO,R.EMA xx.<br />

in&.<br />

%idrn’~ piefb%<br />

Nam centrum illud (per<br />

gxogrcd~ik;tur unifosm~tcr in<br />

kegum Coral. 4,) vel quicfixt vql<br />

d,irc&uw, Scd ccntro ill0 fcmpcs~<br />

p-5”.


PROPoSITmo XII. HEOREMA XII.<br />

S&w MO~U perpetuo ugitari, Jed nunquam longe recedere ~2 cott+<br />

~.2uni gradtdtis centro Plunehmm2 ornnium.<br />

Nam cum (per Coral. 2. rop. vxI I.) materia in Sole fit a<br />

mperiam in Jove ut 1033 ad 81, & diftantia Jovis a Sole fit ad<br />

~kmidiametrum Solis in ratione paulo majore; incidet commune<br />

centrum gravitatis Jovis & Solis in pun&urn paulo fupra Gperficiem<br />

Solis. Eodem argument0 cum materia in Sole fit ad ma-<br />

,teriam in Saturn0 ut 241 I ad 13 & difiantia Saturni a Sole fit ad<br />

fimidiametrum Solis in ratione paulo minore: incidet commune<br />

centrum gravitatis Saturni 82 Solis in pun&urn paulo infra Superfkiem<br />

Solis. ,Et ejufdem calculi vefiigiis infiiitendo ii Terra &<br />

Planeta: omnes ex una Solis parte confiflerent, commune omnium<br />

centrum graviratis vix integra Solis ,diametro a centro Solis dietaret.<br />

Aliis in cafibus diitantia centrorum femper minor ek<br />

Er propterea cum cencrum illud gravitatis perpetuo quiefcit, Sol<br />

pro vario Planetarum fitu in omnes partes movebitur, fed A ten*,<br />

$ro illo nunquam .longe recedet,<br />

Gwol. Hint commune gravitatis scentrum errg, Solis & Planetarum<br />

omnium pro centro Mundi halbendum efi. Nam cuti<br />

Terra, Sol & Planets omnes gravitent in k mutuo, & propterea,<br />

pro vi. gravitatis ‘iuat, fkcundum leges motus perpetuo agitentur<br />

: perfpictium efi quod horum cetitra. mobilia ro Mundi<br />

centro Qukfcente haberi nequeunt. Si corpus illu if in centro<br />

locandum efEt in quad corpora omnia maxime gravitant cuti<br />

vulgi efl opinio) privilegium ifiud co~loedendum efEt Soli.<br />

Cum autein Sol moveatur9 eligendum erit pun&urn quitfiens,<br />

a quo, eentrum Solis quam minitie d&edit, . & %a quo idem, a&<br />

hut minus difcederet, ii modo Sol denfior effet & majors ut:<br />

minus moveretur. .


hmt% m@~enhw in Wipfzbtis timbilicum bubeBt;bns ig &etiztro<br />

SO~J 3 & radiu ad cm I IWZZ i&d dm%s me&s deJcribun,t<br />

temporibtis jWoportionales.<br />

Difjputavimus fupra de his motibus ex Phznomenis. Jam cogr<br />

nitis motuum principiis, ex his colligimus motus cmleftes a priori.<br />

Quonlam pondera Planetarum in SoIem rllnt reciproce UT<br />

quadrata difiantiarum a ccnrro Solis; ii SoI quiefceret sz Planetz<br />

reliqui non agercnt in Cc mutuo, forenc orbes eorum Ellipti&<br />

Solem in umbilko communi h nte~, & arez defcriberentur temporibus<br />

propartionales (per op. I. & XI, & Coroi. II. Prop0<br />

XL I x Lib. 1.) A&Cones autem Planetarum in 1Te mutuo perexiguz<br />

CUnt (ut: pofint contemni j & motus Tlanetarum in JUi~fibus.<br />

circa Sp1em mobilem minus perturbant (per Prop. ~xvr. Lib.<br />

quam G motus ifki circa Solem quiefcentem peragerentar.<br />

A&o quidem Jovis in Saturnurn non efi omnino contemnenda.<br />

Nam gravitas in Jovem efi ad gravitatem in Solem (paribus difiantiis)<br />

ut 1 ad 1033 j adeoque in conjunCtione Jovis & Saturn&-<br />

quoni,akn difintlein Saturni a Jove eft ad dillantiam Saturni a 8Sole.<br />

kre ut 4 ad ‘9, wit gravitas Saturni in Jovem ad gravitatem Sa-<br />

Curni in Soicm u’t $1 ad I 6 x 2,033 ku I ad 20$ circiter. Et<br />

hint oritw per:turbario or’bis Saturni in fingulis Planets hujus<br />

CU~YI Jove conjun63ionibus adeo fenfibilis ut ad eandem Afirbnomi<br />

harcant. Pro vario iitu Planets in his conjun&ionibus, Eccentricitas<br />

ejus nunc augetur nund ;diminuitur, Aphelium nunc promovetur<br />

XH.HX forte retrabitur, & medius motes per vices acccIcrarur<br />

RZ retardatur. Error tamcn omnis in niotu ejus circum So-<br />

]c-tn a ranta vi oriundus (prnterquam in note media> cvitari fere<br />

PC+$ .c~~nltj,tucnd;o um’bi’licum, inferiore I: 7 Orbis ejus in commwi<br />

;ibll:tro &z&il;atis Jovis & Solis (per Prop, Lxvx I. Lib, I.) Sr propter&‘ubi’<br />

maximus efi, vix fuperat minut\? duo prima. Et error<br />

ximu.s.in ‘motu media vix filperat minuta duo prima annuatim.<br />

&nju~~&ione autem Jovis 62 Saturni gravitates acceleratrices<br />

&&,in Sat~~raum, Jo+ in S~turnurn & Jovis in Sokrn funt fere<br />

u#j -J& $31 & E22c$.-~* ku ~zky~, adeoque d,iEerentia gravi-<br />

.,<br />

fatum Solis ,in SarMgblum, & Jovis in Saturnurn CR ad gravitatem<br />

Jovis ,


4 r<br />

ih: VI v >I D I Jovis in Solem ut: 65 ad 124986 feu I ad 1923. Huic aute<br />

sy5T B &*T E ‘fcre~~.~i~ proportionalis efi maxima S aturni efkacia ad perturban-<br />

dum motum Jovis, & propterea perturbatio orbis Jovialis long@<br />

minor 4% quam ea Saturnii. Reliquorum orbium perturbationes<br />

$.mc adhuc longe minores, prazrerquam quad Orbrs Terrzz f&Gbiliter<br />

perturbatur a Luna. Commune centrum gravitatis Terra<br />

& Lunar, Ellipfin circum Solem in umbilico pofitum percurrit, Sr<br />

radio ad Solem dutto areas in eadem temporibus proportionales<br />

defcribit, Terra vero circum hoc centrum commune mticu men-<br />

$Iruo revolvitur.<br />

PROPOSITIO XI% THEOREMA Xf%<br />

Or&m Apheb<br />

& Nodi quieJizdW<br />

aphelia quiefcunt , per Prop. XI. Lib. I. ut & Orbium plana<br />

per ejufdem Libri Prop. I. & quiefceneibus pIanis qulefcunt Nodi.<br />

Attamen a Planetarum revolvenrium & Cometarum a&ibnibus iti<br />

.fe invicem orientur inzqualitates aliqux, fed quz ob parvitatem<br />

hit concemni poffunt.<br />

Curo2: I, Qiekunt etiam Stellz fixae, .propterea quod datas ad<br />

Aphelia Nodofque pofitiones krvant.<br />

Cowl. 2. Ideoque cum nulla fit earum parallaxis GnfibiIis ex<br />

Terra motu annuo oriunda, vires earum ob immenfim corporum<br />

dioantiam nullos edent: fenfibiles effefius in regione Syfiematis<br />

nofiri. Quinisno Fix= in omnes czeli partes‘ zqualirer difperfiz<br />

contrariis attraeionibes vires mutuas defiruunt, per Prop. LXX:<br />

Lib. I.<br />

Cum Planeta Soli propiores (nempe Mercurius, Venus, Terra,<br />

& Mars) ob corporum parvitatem parum agant in fe invicem:<br />

horum Aphelia & Nodi quiekent, nifi qwtenus a viribus Jovis,<br />

Saturn;, Sr corporum fuperiorum turbentur., Ec inde colligi potefi<br />

per theoriam gravitaeis, quod hoium. Aphelia .moventur aliquantulum<br />

in confequentia refpe&u fixarum, idque in proport+<br />

one fefquiplicara diftantiarum borum Planetarum a Sole. Wt fi<br />

Aphelium Martis in annis cent-urn conficiat 35’ in confequkntia<br />

refpe&ti fixarum j Aphelia Terra, Veneris, & Mercurii jn annis<br />

centum conficient. 18’. 36”) IX’. 27’, & J.,‘. tptt refpe&ive.z Et hi<br />

matUs ob parvitatem, negliguntur in hat Propofitione.


Cayicllda: fUfIt 1132 in rathe fubkfquiplicata temporum perbs<br />

dicorum, per Prqp. XV. Lib. I. deindc figillatim augcnda in rati-<br />

One fUlmma= maflarum Solis & Planetx cujdque revolvelltis ad<br />

primarm cluarum medIe proportionalium inter fizmmam illam 8~<br />

Solen3~ per Prop. LX. Lib. 1.<br />

P~Ql?OSITIO 2-cvI. PROBLEMa 11.<br />

Imenire Qrbium Eccentricitd2”e.r & ,Aphch.<br />

r-oblema confit per Prop, XVIII. Lib. I.<br />

P 1~OrOSITI0 XVII. THEOREMA xv.<br />

ate? per motus Legem I, 8-z Coral. 22. Prop. LxvI. Lib. Ill’.<br />

Q_uoniam vero Lunz, circa axem fuum tmiformitcr revolventis9<br />

dies me~~firuus efi j hujus facies eadem ulteriorem umhilicum orbis<br />

ipfius fernper refpicict , & propterea pro firu umbilici iliius<br />

deviabit hint inde a Terra. kkw eR libratio in longitudinem.<br />

Nam l&ratio in ‘latitudhem orta eR ex inch&me axis Lunaris<br />

ad planurn orbis. Porro 11332 ita 6% habere, ex Phznomenis nianifenturn.<br />

cfi.<br />

Edanetae fpbIato omni motu circulari diurrlo figwarn Sphxricam,<br />

& ~q~~alern undique part&m gravitatem, aI3%&are deberent. E)cr<br />

motuxn ihm circularem fit ut partes ab axe recedentes juxta<br />

xquaxmm afcendere, conentw - ldeoque materia ii fluida fit<br />

1 t ccc<br />

lhXf.fti<br />

.


PIA<br />

MATI-IEMATICA.<br />

atitudine &zi$e$a’d Fkr$wz~7az ad minuta ficunda I, 11t 1: c<br />

-ofcilllantis Iongitudo efi pedlam triutn Farifienfium & lhenrum 8;. TL:R’rKUs~<br />

]Ec longitude quad grave tempore minuti unius Cccundi cndcndo<br />

cdetiribit, CRC ad dimidiam longitudinctn pcnduli hujus, in dtaplicata<br />

ratione circumferentia circuli ad diametrum cjus ( ut indicavit<br />

&tgezziza.s) ideoque efi pedum Parificnfium I 5, dig. I, lin. zr-$, ktl<br />

kmm.am 2 qq&.<br />

379<br />

CarpUS in circulo, ad difiathun pedum ry~qy53y a centro?<br />

fingulis diebus fidereis horarum 23, $6’. 4” wniformiter revoIvens~<br />

ternpore minuti unius Cecundi dckribit arcum pedum 143&22;l<br />

cujws finus verfus efi pedum o,osz~~s~~~ ku linearurn 7,~+0d+<br />

ldeoque vis qua gravia defcecendunt in Latitudine Zwtrh~, elk ad<br />

vim centripetam corporum in Aquatorc, a Terrx motu diuraao<br />

priundam, ut 2~74’~~ ad 7,5+06+<br />

Vis cenutrifuga corporum in A?quatorc, tfi ad vim ccntrifugam<br />

gua corpora dire&e tendunt a Terra in Latitudine Lateth gra-<br />

.duum 48,. 50’, in duplicata ratione Radii ad hum complementi<br />

Eatitudinis illius, id ef?, ut 7,$406.4 ad 3,267. AddatLw hzc vis<br />

GUI vim qua gravia defcendunt in Lathdine I&tebLLl, & corp~rs<br />

in Latitudine EM&~ vi rota gravitaris cadcndo, tcmporc mintlci<br />

vnius ficundi dekriberet lineas 2 x77,32’ f&a pedcs Parifie~&s .I 5,<br />

chg. I> & lin. 5,j3. Et vis tota gravitatis in Latitudinc illa, cric<br />

ad vim cenrripetam cprporum in &qwatore ‘I’errlc, UC 2 177~~2.<br />

ad 7, $4OQ, fkL1 128$J ad I.<br />

Unde ii AT B& figuram ‘I’errg defignet jam non amphs<br />

Sp~kzricam ,fed revoletione Ellipkos circum axem minorem P g,<br />

g&tam, fitque dC$Jqca w-d%3 aqu;r: plcna,<br />

a polo $Q ad cenrrum Cc, & inde ad<br />

2Equatorem Jlz pcrgens: debebit pondus<br />

aqwe in canalis crLLre AC CAT, effe ad pondus<br />

a~~,~tus in crure alter0 JZQZ’CS ut z8p ad 288,<br />

eo quad vis cantrifuga ex circulari motu<br />

orta partem unam e ponderis partibus 283<br />

$Winebit’ ac detrahet, & pondws 286 in al-<br />

:OXO crure hRinebit reliquas. Porro (ex<br />

Propofitianisxcl. Cor$lario kcundo, Lib.1.)<br />


4 “3(-J<br />

3”<br />

Pa Mv:;ur ad diametrum .&B ut IOO ad 101 : gravitas 113 loco Kin Terram,<br />

SYSTEA’A’rC foret ad gravitatem in eodem loco g in Sphsram centro C radio<br />

PC vel RC del’criptam, ut 226 ad I 25. tit eydyzrn argumenta<br />

gravitas in loco 4 in Sphwoidem, convolutione E?lltpcCo~ AI> .Bg<br />

circa axem A B dcfcriptam, ei1 ad gravlca,tern in eodem loco .A in<br />

Sph~~ram centro 6: radio AC dekripram, UC I z f ad 126. ?M autern<br />

oravitas in loco A in Tcrram P media proportionalis inter<br />

graviyates in di&am Sphzroidcm & Sphazram : propterea quad<br />

Sphara, diminuendo diametrum !J?‘g in ratione IOZ ad IOO x<br />

vertitur in Aguram Terrs j & hx figura diminuendo in eadem<br />

ratione diametrum tertiam, quz diametris duabus A B, P $I& perpendicularis<br />

efr, verritur in diELam Splwroidem j & graviras in<br />

A, in cab ucroque, d.iminuitur in eadem racionc quam proximc,<br />

Eit igitur gravitas in A in Sphxam centrs<br />

C radio AC defcriptnm, ad gravitatem in<br />

A in Terram ut I 26 ad I 25$, & gravitas<br />

in loco R in Sphleram centro C radio %C<br />

deicriptam, elt ad gravitatem in loco A in<br />

Sphzram centro C radio AC defcriptam,<br />

in ratione diametrorum (per Prop. LXXLI.<br />

Lib.l.) id efi, ur loo ad IOI. Conjungantur<br />

jam hz tres rariones, i 26 ad 125, I 26<br />

ad 12 5: z & 100 ad 101: Sz fiet .gravitas<br />

in loco 2 in Terram, ad graviratem in loco A in Terram, ue:<br />

926X126X xoo ad I~~X.I~~~XIOI~ km ur; 501 ad 500.<br />

Jam cum (per Coral. 3. Prop. xct. Lib. a) graviras in canalis<br />

crure urrovis ACca vel 2Ccq fit ut diiIantia locorum a centro<br />

Terrzj fi crura ilfa firperficiebus tranfierfis & aquidifianeibus difiinguantur<br />

in partes totis proportionales, erunr pondera partium<br />

iingularum in crure ACcu ad pondera partium totidcm in crnre.<br />

altero, ur magnitudines & gravitates acceleratrices conjun&im j id<br />

eD, ur IOI ad 100 & 500 ad 501~ hoc elt, ut 505 ad 501. AC<br />

proinde fi vis centrifuga partis CUJUfqUe in crure Acca ex rnotu<br />

diurno oriunda, fuiffet ad pondus partis ejufdem ut 4 ad 505, eo<br />

ut de pondere partis cujufque, in partes fo5 divifo, partes quaa<br />

tuor derrahcrer 5 manerent pondera in utroque crure zqualia, &<br />

propterea fluidum confifieret in 3equllibrioi Yerum vis centrifuga<br />

parris cujufquc eR ad pondus ejucdem ut I ad 289, hoc efi, -vis<br />

centrifuga quz deberet efi ponderis.pars & efi tmtwn pass %-&<br />

Et<br />

AOi


PRI NGIPIA MATHEMATleA. 3’31<br />

Et proptcwa dice, ficundum Regulam auream, quod G vis tenrrifuga<br />

& faciaC ut altrCUd0 aqua2 in crure ACca fuperet alticu- Tki;lj;I~.<br />

dinem aqua in crurc $?C’cq pate cer~tefima totius altirudinis :<br />

vis centri&ga .i-i 5 facier ut cxcefftis altitudinis in crure ACca !lc<br />

altjtudinis In crure alter0 8Ccq pars tantum -;I,-. Efi igitur dia.-<br />

meter Terraz fecundurn zquatorem ad ipfius diametrum per poles<br />

UC 230 ad 229. Ideoque cum Terra kmidiarneter mediocris, jux:a<br />

menfilram CuJki, fit pedum Parifienfium 19699539, fku milliarium<br />

3939 (pofito quod milliare fit menfura pedum 5000) Terra alliof<br />

erit ad Equatorem quam ad Bolos exceffu pedum 8j820, ku<br />

milliarum 172,<br />

Si Planeea major fit vel minor quam Terra manente ejus denfitate<br />

ac remporc periodic0 revolutionis diurm , manehic proporrio<br />

vis centrifuga ad gravitatem, & propterea maliebit eriam<br />

proportio diametri inter polos ad diametrum fecundurn aquacorem.<br />

At fi motus diurnus in ratione quacunque accelerecur vel<br />

retardetur, augebitur vel minuerur vis centrifuga in duplicata illa<br />

racione, & propterea differentia diametrorum augcbirur vel minuetuc<br />

in eadem duplicata ratione quamproxime. Et fi denfitas<br />

Planers augeacur vel minuatur in rarione quavis, gravitas etiam<br />

in ipfum tendens augeblrur vel minuerur in eadem ratione, &<br />

differentia diametrorum viciflim minueeur in ratione gravitatis<br />

au&z vel augebitur in ratione gravitatis diminutz. Unde cum<br />

Terra refpe&u fixarum revolvatw horis 23. 56’, Jupiter autem<br />

horis pp 56’, fintque, temporum quadrata ut 29 ad 5, & denfitntes’<br />

ut 5 ad I : diRer,entia diametrorum Jovis erit ad ipfius diametrum<br />

minorem ut “j’ X + X & ad 13 Teu I ad 8 quamproxime. EB<br />

igitur diameter Jaws ab oriente in occidentem duBa, ad ejus dia-<br />

metrum inter polos ut y ad 8 quamproxime, & proprerea diamsrer<br />

inter polos efi 35:“. Mac ira ie habenr ex hypothefi quod<br />

uniformis fit Planetarum materia. Nam fi materia denfior fit ad<br />

centrum quam ad circumferentiam ; diameter qw ab.. oriente in<br />

occidentem du’citur$.erit adhuc major.<br />

Jovis ,vero. diametrum qua? p.olis ejus interjacee minorem effe<br />

diamecro alcera CU@S dudum obfervavit, Sr Terra diamecrum /<br />

infer ~010s minorem effe diametro altera gatebit per ea qw<br />

&centur in Progofitioeic kquente.


Plw,QPQSB.TIQ RQBLEMA IV.<br />

EpJ;venire g+ inter jTe cmparare<br />

~egiom%us dbuerjs.<br />

Pondem corgoru~ in Terra? b.+~<br />

Qoniam ponilera inazqualium crurum canalis aqweaz ACRqsti<br />

,azqualia fiint j & pondera parcium ) cruribus totis proportional;um<br />

& fimiliter in tot% fitarum, funt ad invicem ut pondera rotorurn,<br />

adeoqw etiam zquantur inter fe; @runt pondera lrqualium .& in<br />

.cruribus fimilicer Gtarum parti,um reciproce ut crura, id eR, reciproce<br />

ur 230 ad 227. Et par eiE ratio homogeneorum & aqualium<br />

quorumvis & in canalis crurihus fimili.rcr fitorum corporum.<br />

Horum .pondera d’unt reciproce ut crura, id eit, reciproce UC difianti3:<br />

corporum a centro Terra Proinde ii corpora in fupre-<br />

-mis canalium partibus, five in fiperficie Terra COIlfifiaIlt~j erunt<br />

,pondera eorurn ad invicem reciproce ut difiantiz eorum a centro.<br />

ti,e eodcm argumenro pondera , in aliis quibufcunque per toram<br />

Terra fiperficiem regioni’bus, font reciproce ut difiantia locorum<br />

a ccntro j & propterea , ex Hypothefi quod Terra SphErois fit,<br />

danrur proportione.<br />

XJnde tale confit Theorema quod incrementurn ponderis persgendo<br />

ab AQuatore ad Poles, fit quam proxime ut finus veriils<br />

Latirudinis duplicataeg vel, quad perinde efi, ut quadratum finus<br />

aeQi Eatitudinis. Et in eadcm circicer ratione augentur arcus<br />

graduum Latitudinio in Meridians. ldeoque cum Latitude LIIG-<br />

.tetid T;P,rzj%rwm fit 48 gr, so’, ea locorum fub Bquatore oog~ oo’,<br />

& ca locorum ad Polos po gr* & duplorum finus verG fint I 1334,<br />

ooooo 8r 20000, exifiente Radio ~oooo, & gravitas ad Polum fit<br />

ad gravitatem iilb aquatore ut 230 ad 229, & exceffus gravitatis<br />

ad Polum ad gravitatem Cub Ajquatore ut I ad 229 : erie exceffus<br />

gravitatis in Latitudine Lutetis ad gravitatem fib Aquatore,<br />

,ut I x&$&g ad 227, feu 5667 ad 22p0000. Et propterea gravitates<br />

totx in his Iocis erunt ad invicem UC 2.295667 ad 2290000, Qare<br />

cum longitudines pendulorum zqualibus temporibus ofcillantium<br />

fint ut gravitates, & in Latitudine Ltittetile T’arzjG~rw~ longitude<br />

penduli fingulis minutis kcundis ofcillantis fit pedum trium Parifienfiurn<br />

& linearum 8$: longitudo penduli fub Bquatore fuuc<br />

perabitur a longitudine fynchroni penduli Tarz$ez@, exceflk Ii-<br />

.nez unius & 87 partium millefimarum linez: Et fimili compute<br />

confit Tabula kquens.


Gr.<br />

0<br />

f<br />

10<br />

15<br />

20<br />

25<br />

30<br />

d,5<br />

40<br />

I<br />

2<br />

3<br />

4:.<br />

45<br />

6<br />

Ped. Lin. Hexapcd.<br />

ii - 75468 56YQP.<br />

* 7,4w SW4<br />

3 a 79526 56Y3I.<br />

3 ’ 73596 569 r9.<br />

3 ’ 7369% 56996<br />

3 * 7,811 57042<br />

3’ * 7,948 57096<br />

3, * 8,099 5715r<br />

3, ’ 8,=51 572’8<br />

3 * kY4 57231<br />

3 ’ 8,327 57244<br />

3 * 8,361 57257<br />

3 •<br />

8,394 57270<br />

3 ’ 8,428 57283<br />

3 • 8,46; 57276<br />

3 ’ 8,494 57309<br />

3 * tLr28 57322<br />

3 ’ 8,561 57335<br />

3 - 8,573 57348,<br />

3 •<br />

fh7 sb 57411<br />

ii . f-b907 57470<br />

’ 9s44 57 524<br />

3 ’ 9,161, 57570<br />

3 ’ 9,258 57607<br />

3 •<br />

3 •<br />

3 •<br />

33329 ‘57635<br />

Yy37” 57652<br />

9,387 57657<br />

~o-nfitat aatem per hanc Tabulam, quod graduum inzqualitas<br />

gam> parra fit,. LIE in rebus Geograp+is figura Terra pro Sphagica<br />

h,aberi poi’iit~ quodque lnaqualltas diametrorum Terra Facilius<br />

EC certius’ per cxperimenta pendwlorunl deprebendi paflit ml<br />

etiam pm &$ees LUlXEj qU2m per arcus Geographice mcnhraros.<br />

in ~IMleridianlo.<br />

l!-.kee \


.<br />

y”, F &I \J P, D I sac ita k habent ex hyporhefi quod Terra ex uniformi ma- ::<br />

5 TSTEMA~T’F. ceria confiac. Nam G materia ad centrum paulo denfior iit quam<br />

ad fuperficiem 9 dif-lkrentia pendulorum Sr graduum Meridiani<br />

~~4~10 majores erunt quam pro Tabula prazcedente, propcerea :<br />

cj”od ii materia ad cencrum redundans qua denfiras ibi major I<br />

redditur, ikbducztur IL feorfim fpe@etur, gravitas in Terram rc.-<br />

]iquam wniformiter de&m, erit reciproce UC difiantia ponderis ,<br />

a centro j in materiam vero redundantem reciprocc ut quadracum<br />

difiantiz a materia illa quamproxime. Gravitas igitur fuub aquatore<br />

minor efi in materiam illam redundantem quam pro compm0<br />

iuperiore : & proptereaTerra ibi, propter defeQum gravitatis,<br />

paulo altius afcendet, & exceffus longitudinum Pendulorum &<br />

graduum ad poles paulo’ majores erunt quam in przcedentibus<br />

definirum ek<br />

Jam vcro Akonotni aliqui in longinquas regiones ad obkrvationes<br />

Aitronornicas faciendas miffi, invenerunc quod horologia<br />

ol’cillatoria tardius moverentur prope Bquatorem quam in regionibus<br />

notiris. Et primo quidem !D.RRicber hoc obfervavit anno<br />

1672 in infula Cu;v6’?2?2~. Nam dum obkrvaret tranfitum Fixarum<br />

per meridianurn menfe Augz#o, reperit horologium &urn rardius<br />

moveri quam pro medio mutu Solis, exifknte differentia 2’. 28”<br />

lIingulis diebus. Deinde faciendo ut Pendulum fimplex ad minuta<br />

finguln fccunda per horologium optimum menfurata ofcillaret,<br />

lltxotavit longitudinem Penduli Gmplicis, & hoc fecit &Pius fingu-<br />

Iis reptimanis per men& deccm. Turn in GaZGiam redux contulic<br />

longirudinem hujus Penduli cum longitudine Penduli T’ariJieen~s<br />

(qt~z erat trium pedum Parifienfium, & o&o linearum cum tribus<br />

quintis partibus linez) & reperit breviorem effe, exifiente differentia<br />

line,?: unius cum quadrante. At ex tardicare horologii<br />

ofcillatorii in Cuyznna, dift’erentia Penduiorum colligitur efk linea:<br />

unius cum femiffe,<br />

PofIea likllehs nobler circa anr,um 1677 ad inhlam $4 Heh<br />

.Zend navigans, reperir horologium filurn oiillatorium ibi tar&us<br />

moveri quam Londini, fed dif?eren tiam non notavit.<br />

.<br />

Pendulum<br />

vcro brcvius reddidit plufquam o&ava parte digltl, ku linea ulna<br />

cum lemiffe. Et ad hoc efficiendum, cum liongirudo cochke in<br />

ima parte penduli non Tufkeret, annulum ligneum thecaz cochkz<br />

& ponderi pendulo interpoi‘uit.<br />

Deinde anno 1682 9. Ydrin 8z 22. Des Hiyes invenerunt Bon-<br />

:$cl~dinem PendLali fingulis minutis kcundis ofcillantis in Obfer..<br />

yatorisr


PliA MArI-IEMAreeA. 38s<br />

vatorio R&o ~arz$enfi effe ped. 3, lin. 8;. Et in infula GOWLZ ~lnlcn<br />

eadeh methad longitudinem Penduli fynchroni invcnerunt effc TcrtTtws*<br />

ped. 3. h G3 cxiifente longitudinurn ditFerentia lin. 2. Et eodem<br />

-XHIO ad infidas Gti~du~oz~parn or Martinicam navigantes, invenerunt<br />

hngitudineu~ Penduli fvnchroni in his incuhs tire ped. 3, Iin. 6;.<br />

RAbaC ZJ- Gwpdet iiliuS anno 1697 menk Jz4Zi0, horologium<br />

hum okillatohm ad motum Solis medium in ObKervatorio Regio<br />

Tar&M’ fit aptwit, ut tempore fatis long0 horologium cum motu<br />

Solis congrueret. Deindc U&X$ponern navigans invenit quad<br />

me& ~omwabri~ proximo horologium tardius irct quana priLls><br />

exihnte differentia 2’. 13” in horis 24, Et menk Martio k-<br />

quente TLWLJ~~&CZP.RZ navigans invellic ibi horologium fuum tardius<br />

ire quam Tdrifih , exificnte difFerentia 4’. 12” in horis 24.. Et<br />

affirmat Pendulum ad minuta fkcunda ofcillans brevius fuiffe U/J/-<br />

~Z&ont’ lineis 2$ & Tar&b& lineis 35 quam Pa$2. ReAius pofuifkt<br />

diff’erentias eirc L-$ & 2,~. Nam IIZ dhrentiaz difkrentiis<br />

temporum 2’. x3”, & 4’. 12" refpondent. CraXioribus hujus<br />

Obfervationibus minus fidendum efi.<br />

Annis proxirnis f IGyg & 1700 ) 22. Des Hayes ad Awzericam<br />

denuo navigans, determinavit quod in infulisCa~enn~ & Granadz<br />

longitudo Penchli ad minuta iecunda ofcillantis, effet paulo minor<br />

quam ped, 3. iin. of, quodque in infiula J’. Ciwz~ophori longitude<br />

illa effet ped. 3. lin. 62, & quod in infula S, ‘Domitici eadcm effet<br />

ped. 3. lin. 7.<br />

Annoquc ~704. 9’. FeuelZetis invenit in Twto-Celo in America<br />

longitudinem Penduli ad minuta fecunda ofcillantis, effe pedum<br />

‘trium Parifienfium & Jinearutn tantum 5IzS, id efi, tribus Fere lineis<br />

brcviorem quam Ltitetid cTarz~orww, Ted errante Obkrvatione,<br />

Nam deinde ad infulam Murtinicam navigans, invenit longitudinem<br />

Penduli ii’ochroni efle pcdum tantum trium Parifien-<br />

Gum Sr: linearurn 5%.


336 m-w4QSQPWI~ NA<br />

DE hj” N 1) 1 Cub Bc denfior ad centrum quam in fodinis prope ~iperfici~~x~<br />

s’s T “” A T li nifi forte calores in Zona torrida longitudinem Pendu]orum ali*<br />

quantulum auxerint.<br />

Obkvavit utique 13. Ticartzu quad virga ferrea, qw ternpare<br />

hyberno ubi ~elabant frigora erat pedis unius longitudme2 ad<br />

jgnem CalefaLta evafit pedis unius cum quarta parte linca. Deinde<br />

‘I). de ZLJ Hire obC3rvavit quad vi~.,gcl ferrea quz tcmporc<br />

confimili hyberno fix erat pedum longttudinis, ubi Soli zflivo<br />

exponebatur evafit kx pedum long~ti~dinis cum duabus tcrtiis<br />

partibus line32 Iln priore cab calor major fuit quam in pofieriore,<br />

in hoc veru major FLliC quam alor esterndr,um parr~um<br />

corporis humani. Nam ~~talia ad Solcm &ivljm valde incalef-cunt.<br />

At virpa penduli in l~orologio ofcillatorio n3nquam exponi.<br />

lrolet calori Solis zeitivi, nunquam calorem concipit calori<br />

externz hperficiei corporis humani zqualem. Et prophereJ virga.<br />

Penduli in horologio tres pcdes longa, paulo quidem longior<br />

eric tempore ;L’fiivu quam hyberno, i’ed excefft~ quartam partem<br />

line32 klnius vix hperanre. Proinde diEerentia tota longtrudks<br />

pendulorum qua in dlverlis regiwibus iibchrana i‘unt, dlverfo<br />

calori attribui non pot&. Sed ncqu~ crwribus AiZronomorum 2,<br />

Gdia rnifforum rribuenda efi hz~c dhrentia. Nam quamvis’<br />

Gorum obkrvationes non perfe&:s cqn riianf inr,er Ce, tamen errores<br />

he adeo parvi ut contemni po f lng. Et in hwc concordant<br />

omnes, quod iibchrona pendula Cunt breviora i’ub Aquatore quam<br />

iu Obfkrvatorio Regio bPaCj2en/%, edentc differcntia duarum cirtiter<br />

iinearum feeu ikxcz partis di.giti., Per ob&vationes ‘D. Ai-.<br />

c,&y ig Cgycn~a f&as, dift’erent~~ hit linea unius CUM femi8k.<br />

Error femiffls linea facile csmmictitur. Et 53. ~48s Ii&yes p.oQe;l.’<br />

per ,obf&vatiQnes fuss in eadem inftila fa&as errorem correxitP<br />

ip.~en,ca diffegentia linearum 2 A. S&d & per obfersarioeea in in-<br />

fillis Gorea, Giwdahpdl Martinica, G;m?da, S.~C%~iJlOphWi~ &<br />

8. ~;DO~;B~C% h&as 8~ ad AZquatorem reduh, dlflerenrra illa prodiit<br />

lla.ud minor quam 12 linear, haud major qu?m z$ linearum.<br />

it inter 110s Iimites quantitas mediocris eit 2-6 hearurn. Prop=<br />

rer calores locorun~ in Zona torrida negligamus & partes IineES<br />

& manebit difkrentia.dunrum linearum.<br />

Quare CUQ-I difierencia illa per Tabulate przccdentem,. ex hp<br />

potllefi quod Teyra ex mareria u hiformitw d,cn6 co&at, Gtt. trani<br />

fun3 1-$z line,z: : exce,Kus alcitudkis Twr* ad ~quatorem hpral<br />

;ajtirudille1~~ ejus ad poke,<br />

qui ex~iJt vd~kxiW% V% jalU aU.BuS: ia:<br />

ra tione::


atione ~ifh33tiarum, fiet milliarium 3 1 i”,.<br />

_<br />

Nam tarchas Pen- ._ LI-B p 12<br />

duli iirf3 -BqUatOre defe~um gravitJtis 2I'gUitj 8c quo levior f2fi TnnT*TJ’i’<br />

aulateri.n eo major ~4% debt alticudo ejus, ut pondcrc 13~0 marekUfi<br />

fQb hlis in aequilibrio CuItinent.<br />

Hint figura urr;lbrz Terra per EclipfesLunz dcterminanda, non<br />

Wit otrinino circularis, fed diameter ejlls ab srientc in occidcntcm<br />

d~&:a major erit quam diamerer ejus rib aui1~0 in boreain d&as<br />

excell[iI 5 f” circiter. Et parallaxis maxima LLI~JE in kongitudi-<br />

11em pa1110 major erit quam ejus parallaxis maxima in LatitudinetsI.<br />

AC Terra femidiameter maxima erit pedum ParifikMium<br />

zy767Li3O,.minimapedum 1y6oy8zo &medioc&pedum ry~$$ii.g<br />

q,uarnproxm~e,<br />

Curb gradtls LUJS menkante Tisarto fit hexapedaruti 57060,<br />

menfurante vero Cufino fit hexapedarum 5gzgz : fufpicantur aliqtii<br />

gfaduti utiumquemque, pergendo per G&W atiiI~~ verfus<br />

majorem effe gradu przcedente hexapedis p‘lti*s tiidtis 4%) feu<br />

parte o&ingentefima gradus unius; exiRenteTerra Spharoidc ob-<br />

Ilonga cujus partes ad poles func altifima. Qa pofit6, corpora<br />

omnia ad poles Terra leviora forent quam ad Bquatoiem, &<br />

aItitudo Terra ad polos fiiperaret altitudinem ejus, ad 3cquntorcM<br />

milliaribus fere 95, & pendula iibchrona longiora forent ad .&<br />

quacorem quem in Obfirvatorio Regio l”&%$%?$ eXcCffu fimifis”<br />

digi’ti circitcr ; ut conferenti proportiones hit pofiias cunl p:lW<br />

porticmibus in Tabula precedence pofitis, facile conRabit.’ 6’ed<br />

8t diameter umbra Terra qua: ab aufir,o in boream ducitur, ma-<br />

@ foret quam diameter ejus quz ab oriente in occidcntem ducitur,<br />

exceffi 2’. $4, 6z1.1 parce duodecima diametri Lunz. C&ibus<br />

omnibus Experientia contrariatur. Certe C&%WS, definiendo<br />

gradurn ununi tiffe hexapedarum 57292~ mediuvl inter menfuras<br />

,fias omnes, ex hypothefi de zqualitate graduum aKumpfit. Et<br />

quamvis Tkurtz~ in GaGlid limite boreali invenit gradum paulo :<br />

minorem effe, tamen ~o~woadtis nofkr in regionibt@ mtigis bore-<br />

&bus, menfirando majus intervalluin, izivenit gradtim paulo majm<br />

reti eire quam Ch@h4s invenerat. Et CkfiW’s Jpfe mcnfurani Pi~drti,<br />

ob par-itatem intervalli tienf.u&tL non iatis certam & exa&am ciTe:<br />

judicavit ubi rnenfuram gradus ~nms per intervallum longe majus<br />

defifiire aggreffus efi. Differentiae veto Inter menfuras CuJ%Zi, ‘yicdr&<br />

& J?orwo&i funt: prope inknfibiles, 6r: ab infenfibilibus 013.~<br />

&rvat@nurn erroribus ,facile oriri potyerei ut Nuk~tioncm; his<br />

Tkerr$z praterc3am<br />

Ddd 3t PRO:


DE MUNDI<br />

SY~TE~~ATE<br />

PROP’OSITIO XX<br />

&&a A@.4inoEialia regredi, & axem Term Jinplis rezrolu$<br />

onibus annuis nutando bis inclinarZ in Ecli$icam & his yedire<br />

ad pojfionea priorem<br />

Patet per Coral, 20. Prop. LXVI. Lib. 1, Motu.s tamen ifie<br />

nutandi perexiguus e&t debet, & vix aut ne vix quidem fent<br />

bilk<br />

FROPOSITIO XXII. THEOREMA XVIIX.<br />

Jtfotgs omnes Idmares, 0mneJfue motuum inqwiitates ex ah<br />

tis Principiis con&G.<br />

lanetas majores, interea dum circa Solem feruntwr, poffe alias<br />

ores circum te revolventes Pianetas deferre, & mmores illos in<br />

]Ellipfibus, umbilicos in centris majorum habentibus, revolvi d-ehere<br />

patet per Prop. LXV. Lib. I. Ahione aueem Solis perturbabuntur<br />

eorum motus multimode, iifque adficienrur inazqualitattibus<br />

qu”f: in Luna nofira notantur. Hat utique (per Coral, 2,<br />

3) 4, & 7, Prop, LXVI.) velocius movetur, ac radio ad Terram<br />

&I&O defcribit aream pro tempore majorem Orbemque habet<br />

minus curvum, atque adeo propius accedit ad Terram, in Syzygiis.<br />

quam in Qadraturis , niG quatenus impedit motus Eccentrrcitatis,<br />

Eccentricicas enim maxima eit: ( per Coral. p. Prop. LXVI. ) ubi<br />

Apogazum Lui~a: in Syzygiis verfatur, & minima ubi idem in QLuadraturis<br />

confifiiti & inde Luna in Perig3eo velocior eft & no&s<br />

gropior, in Apogao autem rardior & remotior in Syzygiis quam<br />

in Quadraturis. Progreditur in&per Apogawm, & regrcdiuntur<br />

Nodi, fed motu inxquabiii. Et Apogsrum quidem (per Coroli 7;<br />

& 8. Prop. LXVI.) velocius progreditur in Syzygiis his, tar&us<br />

regreditur in Qadraturis, & excel& progreh fupra regrerum<br />

annuatim fertur in confequentia. Nodi aurem ( per GoroI. ‘I 1.<br />

Prop, LXVI.) quiefcunt in Syzygiis fuiuis, St velocifime regrediunfur<br />

in Qndraturis. Sed & major efi Luna: latitude. maxima in.<br />

iphs Qadraturis (per Carol. IO. Prop, LXVI.) qwam. in<br />

giis: & motus medms tardier in Perihelia Term (per (29


gzfs<br />

Prop. Lxv Ia) quain in ipfius Afphelio. Atque ha: Eunt. inxquah. LlUr-r.<br />

tat-es infigniores ab Afironomis notats, TfillTlUA<br />

Sunt etiam aIix quadam nondum obiervataz inaqualitates, quibus<br />

motus Lunares adeo perturbantur, UC nulla haQenus lege ad.<br />

Regalam aliquam certam reduci potuerint. Velocitates enim feu.<br />

motus horarii Apogxi & Nodorum Lunz, & eorundem xquati...<br />

ones, ut SZ: differentia inter Eccentricitatem maximam in Syzygiis<br />

8i: minimam in Quadraturis, & inzqualitas qux: Variatio dicitur,<br />

augeatur ac diminuuntur annuatim (per Coral. ~4,. Prop. LXVI.)<br />

in triplicata ratione diametri apparentis Solaris. Et Variatio prz:<br />

terea augerur vel diminuitur in duplicaca xatione remporis inter<br />

quadraturas quam proxime (per Corol. I. & 2. Lem. X. &<br />

Coral. 16. Prop. LXVI. Lib. 1.) Sed haec in;rqualicas in calculo<br />

Afironomico, ad Profihaphzrefin Lung referri folet> Br cum e;b,<br />

confundi.<br />

. Ex ,motibus Luna noftr:1: tnotus anal’ogi Lunarum. fku Satelli.-<br />

tu~ll Jovis Gc derivantur. Motus medius Nodorwn Satellitis extimi<br />

Jovialis, cfi ad motum medium Nodorum Lunx. nofirx, in ratione<br />

compofita ex ratione duplicata temporis periodici Terrycirca<br />

Solcm ad tempus periodicum Jovis circa Solern, & ratione.<br />

fimplici remporis periodici Satellitis circa jovem *ad tcmpus periodicum<br />

Lunz circa Terram: (per Coral. I 6. prop. LXVI .) adeoquo<br />

anais. centum conficit Nodus ifie 8 F* 24’, in antecedcntia. Motus .<br />

medii Nodorum Satellitum interiorum fimt, ad motum hujus, ut.<br />

illorum tempora periodica ad rempus periodicum hujurs, per idem.<br />

Cork)llarium, & inde dantur. Motus autem Augis Satellitis cujufquc<br />

in. confequentia, e fi ad motum Nodorum ipiius in antecedentia,<br />

ut motus Apogzi Lune noitrze ad hujus motum Nodoruin,.<br />

(,pcr idem Coral.) & inde datur.’ Dmnnwi tamen debct<br />

motus Augis fit inventus in ratione f ad 9 vel I ad z circiter, ob<br />

caufam quam hit exponere non vacat. JJquationes maximaz No..<br />

&rum & Aegis Satelliris cujufque fere funt ad zquationes maximas<br />

No&rum & Augis Lunar refpetiive, UF mows Nodorum &-<br />

Aq$s, Sat&turn #knp.ore. unius MdUtionlS- zquatlarlum prio-<br />

RLaMp


39Q PH%LoSoPMI& AE’IS<br />

DC ?dUNDI ruin9 ad ixotus Nodorum 6; Apogzi Luna tempore unius revo~<br />

3 YSYEhlATE ,lutionis 33Juationum polkriorum. Variatio Satkllitis 2 Jove C e*<br />

eati, cfi ad Variacionem Lunzc, UC funr ad inviccm toti mows Np o-<br />

dorum temporibus quibus Satelles & Luna ad Solem revolvuntur,<br />

per idcm Coroilarium ; adeoque in Satellite extimo non fupcrat<br />

5”. 12”‘.<br />

PRQPOSITIO XXIV. THEOREMA XIX.<br />

Mare fingulis diebus tam Lunaribus quam Solaribus bis intumefcere<br />

debcre ac bis defluere, patet per Coral. 19. Prop, LXVL<br />

Lib.1. ut St aqua maxirnam alcitudinem, in marlbus profundis<br />

& liberis, appulrLlm Luminarium ad Meridianurn loci, minori<br />

quam kex horarum fppatio kyui, uti’ fit in Maris Atl~ntici &<br />

~E.z&~pki traRu toto orientali inter G~ZZz’am & Promontorium<br />

Borz~? %pei, ut & in Maris ‘Yal*ijci littore c’hiZen$’ & T’erkzliano:~<br />

in rluibus omnibus Iittoribus aflus in horam circiter tertiam incidit,<br />

nlfi ubi motus per loca vadofa propagatus aliquantulum retardatur.<br />

Horas numero ab appuIfu Luminaris utriufque ad Meridianum<br />

Ioci, tam infra Horlzontem quam f’upra, & per horas<br />

diei Lunaris intclligo vigefimas quartas partes temporis quo Lung<br />

motu apparente diurno ad Mcridianum loci revolvitur,<br />

Mows aurem bini, quos Luminaria duo excitant, non cernentur<br />

difiin&e, fed motum quendam mixtkrn efficient;- In Luminad,<br />

rium ConjunEtione vei Oppofitione conjungencur eofurh effe&.w,<br />

tk componetur fluxus & refluxus maxm~us. In Quadraturis Sol<br />

attollet aquam ubi Luna deprimit, deprimctque ubi Sol attollit,;<br />

& ex effe&unm difik-enria &us omnium minimus orietur. Et<br />

quoniam, experienria teife, major efi eEeAus Lunar quam Solis,<br />

incidet aqua maxima altitude in horam tertiam Lunarem. Ex..<br />

rra Syzygias & Quadraturas, xfius maximus qui cola vi Lunari<br />

incidere kmper deberet in horam tertiam Lunarem, & ibla Solari<br />

in tertiam Solarem, compofitis viribus incidec in tempus aliquod’<br />

intermedium quad tertiz Lunari propinquius efi ; adeoque ia<br />

tranf~ta Lunz a Syzygiis ad Qadraturas, t&i hors t&a Sala&<br />

przedit tertiam Lunarem, maxima acpz altitude przcedet etiam,<br />

tertiam


ga PI-I<br />

‘?h MuNal fubje&um; blocurn huic oppofitumi I, Cd altitudines Maris<br />

,in lock g, f, ?), LL Qinetiam<br />

G in przfata Ellipfeos<br />

prevofutione pun&urn quod- h<br />

vis N dekribat circulum<br />

A? M, ficantem parallelos<br />

;h;f, TV in locis quibufvis<br />

Hi, 27, & zquatorem A E in<br />

S; erit CN altitude Maris<br />

in lwis omaibus R, S, T, fitis in hoc circulo, Hint in revolt<br />

tionc diurna loci cujufvis F, afluxus erit maximu<br />

tertia pofi appulfum Lung ad Meridianum fupra<br />

poftea defluxus maximus in 2 hors tertia pofi, oc<br />

dein affluxus maximus in f hora tertia poit appulfium<br />

Meridianum inka Horizontem ; ultimo defluxus maximus in ,$?+<br />

hora tertia poit ortum Lunx; & affluxus pofierior in f erit mi-<br />

‘nor quam afTIuxus prior in F. Difiinguitur enim Mare totum in<br />

duos omnino flu&cus Hemifpharicos, unum in Hemifphzrio<br />

KHkC ad Boream vergentem , alterum in Hemifphaerio oppo-<br />

Vito Kh kc; quos igitur flu&urn Borealem & flu&urn Aufiralem<br />

nominare licet. Hi flu&us fernper Gbi mutuo oppofiti, veniunt<br />

per vices ad Meridianos locorum fingulorum, interpofiro intervallo<br />

horarum Lunarium duodecim. Cumque regiones Boreales<br />

magis participant flu&urn Borealem, & Auftrales magis Auftra-<br />

Iem, inde oriuntur ~fhs alternis vicibus majores & minores, in<br />

Iocis hgulis extra aquatorem 9 in quibus luminaria oriuncur &<br />

.occidunt. .Efius aucem major, Luna in verticem loci declinante,<br />

in:idet in horam circiter tertiam polE appulhm Lun,?= ad Meridianum<br />

fipra Horizontern, & Luna declinationem mutanre verte-<br />

:tur in minorem. IIt fluxuutn difFerentia maxima incidet in ten+<br />

pora Solititiorum 5 prazkrtim ii Luna: Nodus akendens verf’kur<br />

211 principio Arietis, Sic experientia compertum eLt, quod zefius<br />

.auatutini tempare hgberno fuperent vefpertinos 8~ vefpertini tempore


PRINCIPEA MAT’HEMAT1CA. 533<br />

pore AEvo tiatutinos, ad T&.2fi~tt5Um guickm altitudim quafi ElAFT.IP<br />

pedis unius, ‘ad BriJtoli’nm vero altitudine quindecim digitorum : TERTCwyobfervantibus<br />

C~Zcprel;Ti~ ck J’,~l;vrZo.<br />

Motus’autem hcoiernu~ defcripti mutantur aliquantulum per vim<br />

illam reciprocationis aquarum, qua &Iaris 32fius, ctiam ccflinr-ibus<br />

Ltiminarium a&ionibus, poff‘et aliquamdiu pcrkverarc. ~onkrratio<br />

hzcce mo,tus imp&i minuit difkrentiam zfiuum alterno&<br />

rum \ & afius proxime pofi Syzygias majorcs rcddi t, eoLlue proxime<br />

podt Qadraturas minuit, Unde fit ut aifus alterni ad “I”,+mti,~k~tm<br />

& Brifialiam non molto magis difkranc ab inviccm quam<br />

altitudine pedjs unius vel digitorum quindecim j .urque zfius omnium<br />

maximi in iifdem portubus, non iint primi a Syzygiis, &xi<br />

fertii. Retardantur etiam mow omnes in tranfitu per vada, adeo<br />

UC a&s omnium maximi, in fretis quibufdam & Fluviorum ofiiis,<br />

fint quarti vel etiam quinti a Syzygiis.<br />

Porro fieri poreit UC azIIus propagetur ab Oceano per Fretn dive&<br />

ad eundcm porrum, Ekf citius Crankat per Aqua h-eta qua112<br />

per alia : quo in caf~~ ~fius idem, in duos vcl plures filccefive adveoientes<br />

divifus, componere pofit mocus novos diveribrum generu‘m,<br />

Fingamus altus duos zquaIes a dive& iocis in eundem<br />

gorcum venire, quorum prior przcedat alterum [patio horarum<br />

fix, incidatque in horam tertiam ab apgulfu Lunx ad Meridianum<br />

portus. Si Luna in hocce Cue ad Meridianurn appulk verfibatur<br />

in Equatore, venient fingulis horis Cenis zquales aff-luxus,<br />

qui in mlnruos refluxus incidendo eofdem affluxibus aquabunt<br />

& fit fpatio diei illius efficient ut aqua tranquille iiagnet. Si<br />

Luna tune declinabat ab Bquatore, fient &us in Oceano vicibus<br />

alternis ma-jores & .minores, uri diQum efi 5 & inde propagabunrur<br />

in hunt portum aflhms bini mnjores & birli minores, vicibus<br />

alternis. A.#uxus aurem bini majores component aquam.<br />

altiflImam in medio inter ucrumquez afbxus major St minor faciet<br />

ut aqua afiendae ad mediocrem alricudinem in Medio ipforum3<br />

sr: inter affluxus binos minores aqua af?endet ad altitudinem<br />

minimam, Sic fpatio viginci quatuor horGum, aqua non<br />

his ut f&i folct, fed femel tantum pervcniee ad maximam alcittadinem<br />

& femel ad minimam; & altitude maxima, ii Luna decliaat<br />

in poIum fwpra Horizonrem loci ‘, incidet in horam vel kxtam<br />

Mel tricefitiam al, apptilfti Luna: ad Meridianum, atque kuna de-<br />

&nationem mutallte mutabitur in defluxum, Qorum omnium<br />

e~etiplum, in poctu regni li’wr$G ad Ba6@am, filb l”t$it:j;l;


33~ MUNDI Boreali zogr* 50’. H&ks ex Naurarum Ob~ervhonibus pate&<br />

s KS TEMA T E f&t. Ibi aqua die tranfitum per Aquatorem kquence.<br />

~qyac, &in Euna ad Borcam dechallte inciplt Auere & refluere,<br />

non his, 14~ in aliis POIXU~US, fed kmcl fingulis diebus; or: Z&LB<br />

illcldit in occaCum Lunx, defluxus maxImus in ortum. CUIl%<br />

Lung declinatione augetur hit 3zfius, u@ue ad diem lfepeimam<br />

vel o&avum> dein per alias Piptern dies iifdem gradibus decr.ekit,<br />

quibus antea creverat 5 & Luna declinationem mutante ceffat, acmox<br />

mutatur in defluxum. Incidit eniti Cubinde defluxus in occa~um<br />

Lunac Sr affluxus in orcum, donec Lima iterum mutet :declinationem.<br />

Aditus ad hunt portum fresaque vicina duplex ,paeer,<br />

alter ab Ocean0 Skze@ inter Continentem Ik Mklam LSXO-.<br />

z&m, alter a Mari Iazdico inter Continentem & lnfulam Borneo<br />

An azRus fpatio. horarum duodecim a Mari A.zdico, & Kpatio horarum<br />

fex a Mari Siraenyf per freta ills vcnientes, & fit .in horam terham<br />

& nonam Lunarem incidentes, componanc hujufmodi mows;.<br />

Bjtne alia Marium iilorum condieio) ~obkwtionibus vicinorwm.<br />

lictorum determinandum relinquo.<br />

HaQenus cau.fas motuum Lunz & ‘Marium rcddidi. De qua+<br />

&ate motuum jam convenit aliqua cubjungere.<br />

PROPOSITXQ XXV. PRQB’LEn;a~‘~L


P ~,.,~~El~~~I~~.* g$q<br />

Sole~m. Eat co~poni~tur. ex paattibw $M, L NJ quarwn~ P; M 2% 1,~ 11.1: b!<br />

ipfih~, s-&Z RS~,S TM per.turbat mowmy Lunar; LIE in Libri primi ?‘E1t’r”“<br />

’ B’iop. LXW., & ejus Corollariis empofitum efi. CJ$tenus~ Terra6<br />

&2 EU&l circut31 commuxie gravitatis. centrum rev01vun6u.r~ perturba!bit.ur.<br />

ham. WOWS, Terclr: circa cenwum iHud, a viribus can4fi,miU<br />

libus ;’ fid- Cutnmas tam. viltiwm qyam~motuum refcwe I&t ad: hl<br />

~>~Ws9- k, flIlII~~as:. virium...per lincas ipfis analagas 5YA-4. &z: A~J%<br />

&f@re. wis il?!1$ ( in mcdiocri ha quaatitate), oiE’ ad. vim,<br />

centnpetam, q,Ua Luna, in Orbe ho circa ‘~erram-,quiefcen-tel,~~, a&<br />

difihtltlam! 5? r revolvi poffet, im dulplicata, radone. teCgnporlum<br />

pe~io,dikorum Lunx circa Terram St Terra2 circa SoPem 9 (;pc’r<br />

CO~~Q~. $3 7i E’w~~~L:xv:~.. Lib. I,) hoc efi,, in. duplicata r.atione cl&~<br />

r,um 27. kwr. 7. r/ain.~3~ ad dies 365. hr. G. win.g, id efi, ut IOOC;<br />

ad’ 178-725, Gu r ad x7+@; hvenimus autem in Phopofirione:<br />

quarta quad, fi Terra or hna circa commune gravitatis cenrr’w~~.<br />

revolvaneur, earum dihntia mediocris ab invicem erk 60% ihi.-<br />

diaxnetrorum mediocrium Terrx quamproxime. E-t vis. qua Luraa<br />

Jn Orbe circa Terratn quickentern a d di~fiantiam T T kmidiam-ctrorum<br />

terrefhium 60; revolvi poffet) eft ad vim, qua eodem<br />

tcmpore ad difiantiarn kmidiametrorum 60 revolvi poirec, UT.<br />

60+ ad GO j & haze vis ad vim gravikis apud 110s UC a ad<br />

;Qo X 60 quamproxime. ldeoque vis rnediocris ML, efi ad vim<br />

gragitalis in fiuperficie Terra , ut I x 60: ad 60 x 60 x GO x r78$2-,<br />

fix I ad 6j8092,6~ Vnde ex proportione linearurn ‘IlM, ML,<br />

aatur e.tiam vlis TN: & II,?: funt vireh Solis qwibus Lung motus<br />

gerturbantur. ,$$ El L<br />

P~OPOSITlO XXVI. BROBEEMA VII,


396 SOPHIIE NA14WRAEP.S<br />

-nU MUNbI<br />

ad mediocrem fuam quantitatem TfP, ut at vis TM ad me&o-’<br />

s YSTEMAT E crem fuam quantiratem 3 T I & EL; agenda<br />

k’ecundum perpendiculum ) accelerat vel retardat ipfam, quanturn<br />

accelerat vel rctardat Lunam. Acceleratio illa LurxP in<br />

frantitu ipfiuS a Qadratura C ad Conjun&ionem A, fingulis<br />

temporis momentis fa&a, e it ut ipfa vis acceIerans EL;, hoc en,<br />

lit: $/vw-IC, E xponatur tempus per motum medium Luna-<br />

T6P<br />

rem, vel (quad eodem fere recidit) per angulum CTT) vei<br />

aa<br />

etiam per arcum CF. Ad CT erigatur normalis C G. ipfi (.Z’<br />

zquaIis. Et divifo arcti quadranrali AC in particulas mnumeras<br />

a~~uales Tp, &c. per quas zquales rotidem particulz temporis<br />

exponi pofint , du&aque pi perpendiculari ad CZ”, . jungatur<br />

TG ipfis KP, kp prod&is occurrens in F&f, & erlt Kk ad<br />

t;PK ut Tp ad Tp, hoc efi in data ratione, adeoque FKxKk<br />

feu area F.Kkj9 ut 3T lcTx TT ‘I’, id eff 9 ut EL •<br />

J & compoiite 9<br />

area tota G CKF ut fumma omnium virium EL temporc tiot~<br />

Cfg imgrefl’aruna In Lunam , atque adeo etiam, ut velqcitas hc<br />

furnma


fu Enma genita, id efi, ut acceleratio defcrlptionis are= CTT>‘~& 1,i: :i<br />

incrementurn momenti. Vis qua Luna circa Terram quiefcel]Eem T~:RT~J. 1<br />

ad difiantiam Ty, tempore Cue periodic0 CA‘D UC dierttm 27.<br />

howl 7. min. 43. mdvi poffer, efficerec ut corpus, tempore C‘x<br />

cadendo, del’criberet longitudinem tC I, & velocitarrm iit;lul.<br />

acquireret 3equalem velocitati, qua Luna in Orbe fuo movefur.<br />

Patet hoc per Carol. 9. Prop. IV. Lib. I. Cum auw~~ perpendiculum<br />

Kd in TP demifhm fit ipfius E 6, pars r&a, CC ip-<br />

GUS TP fiu ML in O&antibus pars dimidia, vis E I, in Otlanhbus,<br />

ubi maxima efi, iuperabit vim ML in ratione 3 ad 2)<br />

adeoque erit ad vim illam, qua Luna tempore ho periodlco circl<br />

Terram quiekentcm revolvi poffet , ut IOO ad ; x 17672: i;u<br />

I: 1915, & tempore 42 T velocitatem geflcrnre debercc qu,~ c&t<br />

JO0 . velociratis Lunkis, tempore autem C ‘PA velocitatcm<br />

ECjso;iZ Igeneraret in ratione CA ad CT’ ku T-2’. Expona tus.<br />

vis maxima E L in OEtantibus per arcam FKx Kk refiangulo<br />

-1 TT x ‘-pp ;sequalem* Et velocitas 9 quam vis maxima temp.ore<br />

quovis CT generare poffet, eri‘t ad vclocitatem quam vis omnis<br />

minor E,l; eodem tempore generat, ut re&?ngulum t T&P x c 7~<br />

ad aream KCG F: tempore autem toto CT A, velocitares genit=<br />

erunt .ad invicem ut reQangulum t IT X CA & triangulum<br />

2-6 G,. five ut arcus quadrantalis C A & radius T T. ldeoquc<br />

(per Prop. xx. Lib. V. Hem,) vetocitas pofierick, toto tempore<br />

~genita, erit. pars 100 velocitatis L.LIaX. Huic LuIl32 velocitati,<br />

guz areg momeikk?‘mediocri analoga et?, addatur & auferatur<br />

dimidium velocitatis akerius ; & G momentum mediocre exponnt13r<br />

per numerum 1~915~ fumma 1rpl5-+-50 ‘ku 1196~ exhibebit<br />

momentum maximum arez in Syzygia A, ac difkentia<br />

rxpr5- 50 ;Teu 11865 ejufdeni momentum minimum ill Quadra-<br />

GUI-is. Jgltur area: temporibus zqualibus in Syzygiis Sr Qadraguris<br />

defcripta, limt ad invicem ut I 1965 ad I 1865. Ad momencum<br />

minimum I 186~ addarur momentumj quad fit ad momentorum<br />

dserentiam ‘109 UC trap?@urn FKCG ad triangulum<br />

TCG (vel quad perrnde eR> UC quadrarum Sinus T K ad<br />

quadraturn Radii Tp, id. efi, UC T d .ad Z-55’) Sr hmma exhibebit<br />

momentum areg, ubi ‘Luna efi in 10~0 quovis intcrmeledis<br />

T.<br />

~gc omnia ita fe habent, ex Hypothefi quad SOI & Terra quiefcunt,<br />

&’ Lund tempore Synodico dierum 27. her. 7. min. 43. rewdyitur.<br />

cum atitem periodus SyFodica Lunaris vere iit dierum


3 a.8 P 1-I I E PHI.&<br />

Lit IGWND1 YLlrn 29. bsr. x2. 8~ min. &A augeri debenit momenr0rum inwe..<br />

sr:yc!l~‘r E n~enta in. ragiorwtemporis, id efi, in ratione 1a8o8;~~g adi xoooocx~~<br />

,HO~ pa&o incxementun~ towm3 quad erat pars &$$ rnomcnti<br />

mediocris 9 jam fiec ejufdem pars $&&. ldeoquc mornen turn<br />

are;z in Qgadratura kuns erit, ad ejus momcn~tw-n3., in, Syygia<br />

ut II~OZ~ -“950 ad; 1x023 +po, feu x037)3’ ad;. I ia,~.3.~, 83;. ad ejus<br />

momentum, ubi Luna in alio- quovis,loco intqrxledlo It’- verfi~~r,.<br />

ut 10973 ad! 10973 -+-add; exiitentw vidolicet T’F< zq:uali. DYO;.<br />

Area igitar, quam Luna, radio adi ?ierram: &I&O. fingulis~, ternporis<br />

particulis xqualibus dekxihit 9 41 quam+ proxime ut. f~~rnmai<br />

nunm-i 21946 & Sinue vwi duplicate difiantk Lun3: ai@adra-.<br />

tura proxima 9 in circulo cujw aadius ek uniDas2 H9x1 ital k ha*<br />

bent ubi Variatio in cXkmt,ibus-efi magnitudinis mediocrk Sin<br />

Variatio ibi major fit vel minor; augeri debts ve;l, minui-,Sinus: ilk<br />

,,verfuPs in eadem ratione.<br />

I<br />

p R 0 ,p O”cJ’I -pI 0” JpJ(J7I.I~ p i 0 B”E E;l”ilI!& J,7.1g-a<br />

-EX wotu hwarb i%w %mm&e $$im diF,!r&am a Thwu;<br />

Area, quam Luna. radio ad, T&ram d&o, fingulis, tempc$$;<br />

momentis, defcribit, efb UC, moew horariup IXUXE & quadraturn:<br />

dif+antk Lunar a -Terra~~conjun&im:; & pro@xeak difian& I.une:<br />

a, Terra: efi in r@tione compofita ex. filbduplic~t~;ration~ Aroar C&<br />

re&e & fubduplicata. ratione motes horarii inve&: ,$&I$. 1;,<br />

&‘a&. I. Him da.tur: kma diameter apparens: qui,ppe qxw fis:<br />

.reciproce.ut iphus.~difi~~t.iat a~TerIra. Ten ten&i: kkfinonomi~ qwmi<br />

probex4haw RegulaAoum” Phaensmenisi dongruatr .<br />

~‘kwoZ.~ 2. Mnc: etiam- Orbisti Ijyaaris: aacuratius,:a I?.haz~orncxGs<br />

quam antehac definiri potefii


-@o PlW.JIXOPWI~E NbJ’WRAEIS<br />

‘I?F: I?rUNDl<br />

s Y s ‘I‘ i: b, A a’ e<br />

Qloniam Figura orbis Lunaris ignorarur , hujus vice affimalllus<br />

Ellipfin 2, B CA, in cujus centro I Terra collocetur, & cu-<br />

PUS axis major 59 C Qlradraturis, mhor AB Syzygiis interjateat.<br />

Cum aurem planum Ellipfeos hujus motu angulari circa<br />

Terram revolvatur, & Traje&oria cujus curvaturam confideramus,<br />

ckfcribi &bet in plano quad omni motu angulari omnino dCfli*<br />

tuicur : confideranda erit Figura, quam Luna’ in Ellipfi illa revolvend0<br />

def~ribit in hoc piano, hoc eft Figura Cpa, cujus pun&a<br />

iingula p inveniuntur capiendo pun&urn quodvis F in EIlipfiJ<br />

quad 10cmt Lun;e reprehrer, & ducendo Tp ,aqtialem TT, ea<br />

legc ut angulus T Tp zqualis fit motui apparenri Sol,k a tempore<br />

aadratura: c’ confe&o 5. vel, (quod eodem- ferc recidit) u t<br />

angulus CTp fit ad angulum<br />

CTP ut tempus revolutio- ‘f s<br />

llis Synodics Lunaris ad tem- ; \<br />

~3~s revolutionis Periodicaz .<br />

Ileu “9” 12”.44’, ad 27d. 7L.43’.<br />

Capiatur igitur angulus CTa ,:<br />

in eadem ratione ad angulum<br />

reQum CTA, & fit<br />

longitude Ta squalis longitudini<br />

T./ j & erit a<br />

Aph ha & C ApGs (ilmma<br />

Orbis hujus C;d&. Ra-<br />

‘oiones autem ineundo inve- D<br />

nio quod difFerentia inter<br />

curvaturam Orbis Cpa in<br />

vertice dJ & curvaturam Circuli<br />

centro T interval10 Ti4<br />

defcriptiJ fit ad dift’erentiam *--...<br />

inter curvaturam Ellipfeos in<br />

verrice A & curvaturam ejufdem Circuli, in’duplicata ratione at+<br />

guli C T’P ad angulum CTp; & quod curvatura Ellipfeos in A<br />

fit ad curvaturam Circuli illiusJ in duplicata rationc T.& ad T Cj<br />

& curvatura Circuli illius ad curvacuram Circuli centro T in-<br />

Cervallo TC dcfcripti, ut TC ad TA; hujus autem curvatura ad<br />

curvaturam &kpf’eos in CJ in duplicata ratione TA ad TC; &<br />

CliiYerentia inter curvaturam Ellipfeos in qertice C St ctirvaturam<br />

Oirculi noviflimi, ad difkrentiam inter curvaturam :Figurx: T$ D<br />

in vercice C & curvatwam ejufdem Girculi, in duplicata ratione<br />

Gqy Ii


RPNCI[I>IA IVLA wm ATlCA.. &%-+!?I<br />

anguli Tp ad’ anplum CT?‘. C&x quidetn rationes ex Gnu- t 1 II riI<br />

bus angul0rum contafiw ac diffcrensiarum angulc3rum facile CoIli-. TB NT1 vJ.<br />

guntur. His autem inter fe collaris, pro&t curvarura Figurx Cp a<br />

in n ad ipfirrs curvaturam in C> ut A TC& -+- Iw CTq x A T<br />

ad .CTCZ& -+- a h!TqXCr Ubi numcrus 100000 ZEA- defignac<br />

differentiam quadratorum angulorum (II’ TF’ EX c ‘T,LJ appliadracum<br />

anguli minoris CT”P, ku ( qu,od perifFercntiam<br />

quadratorum teanporq ayd* 711’ 43’, &<br />

applicatain ad quadraturn temporis 27 d* 7 ha 4,~‘~<br />

a defignct Syzygiam Lund, & C ipfius Qadraru-<br />

.ram, propartio jam invcnta eadcm eTii: debet cum proportions<br />

curvatur.~ Orbis L~uxe in Syzygiis ad ejufdcm curvaturam in<br />

Qadraturis, quam fupra invcnimus. Proinde ut inveniacur pro--<br />

portio C’T ad A?T, duco extrcma & media in fe iuvicem. Et<br />

termini prodeuntcs ad AlY. CT’ applicati, fiunt zo62,79 CTq q<br />

-2rt5~pG~~~XC~cub + 368676T\a %AT%C*Tg+ 3634zATq<br />

%CQ- 3620447 N X e&if-y X CT-t- 2191371 N X d’~cztb -I-<br />

40~1,4Az34--0. Mic pro terminorum AT Pr CT kmifi.mma<br />

N kribo” r\, & pro eorulldem femidifkrenria poncndo X, fit<br />

CT=r+x, & AT= I --x: quibus in xquatione fcriptis 9 &<br />

aquationc prodeunte refoluta, obtinetur x zqualis OP~IY~ Gi<br />

inde kmidiarncter CT fit r,oo719~ & femidiameter AT 0~992519<br />

qui numcri filtlt ut 70&, & 159%“~ quam proxime. ER igitur difi:allria<br />

LL~~E a Terra in Syzygiis ad ipfius dihntiam in Qadraturis<br />

(fcpofi ~a fcilicet Eccentricitatis confiderativne) ut 6yA ad<br />

70~~~) vex numeris rotundis ut 6p ad 70.<br />

PRO POSIT10 XXIX. PROBLEMA X.<br />

Oritw bxc inxqualitas partim ex -forma Elliptica orbis Lunaris,<br />

pnrcitn cx ixwqualitate momento.rum arex cpam Lum rack3<br />

ad Tcrram d0o defcribit, Si Luna ‘P in EllipG D B&IA circa<br />

Terram in ccntro EllipCeos quiefcentem moveretur9 & radio fz”“F<br />

ad TerratB d&o dckriberet aream C’TP tempori proportionalem<br />

3 eilTet aurem Ellipkos kmidiameter maxima CT ad kmidiametrnm<br />

minimam TA ut 70 a$ Gp: foret tanjgens anguli<br />

GTP ad tag3getztcm anguli ~OCLIS mcdii a %adratura, C cogyutati><br />

ut llipfcoa femidiameter F:f! ad qufdem fem~d~ama~qm<br />

2-c


40% PEIILosoPwI& T&4<br />

r)g blur:~r TC @I 69 ad 70. Debet autem defcriptio are2 C?” P2 iq pi+<br />

SY-.cTE’lATE~reRu Lunar a Qadratura ad Syzygiam, ea ratioqe, s.ge&wl, UB<br />

ijus momentum in Syzygia Lunz 17~ ad ejys IFO~E~&I~ in f&ladraturn<br />

UC I 1073 ad 10973 1 utque exceffus mo~~$J?Fi F’!? kW<br />

qucjvis intcrmedlo ‘P itipra momentum in Qadratura $6 YC ~sas<br />

dratum finus anguli CIT. Id quod i’ritls accqtate. Get? fi F?R~<br />

gens anguli CT’P diminuatur in fLlbduplicat+ ~~!IQII~ nut$w&<br />

10973 ad numerpm 11~73, id efi, in ratiwe 111~rneri 68,48a~ %k<br />

numcrum 63. c&IO paQ0<br />

tangens anguli CT’P jam e- :>; s<br />

rit ad tangentem mo,tus medii<br />

ut ~8@77 ad 70, &Z an,-<br />

gulus CTT in CXkanribus,<br />

ubi motus mcdius elt 45 gr*<br />

kvenietur 49”‘. 27’. 28”. qui<br />

&bdu&us de angulo motus<br />

medii 45 gr. relinquic Va,riarionew<br />

rnaximani 32’. 32”.<br />

&.ZC ita fe haberena ii Luna,<br />

pergendo 4 Qadratura ad<br />

Spzygiam, defiriberet angu-<br />

Iurn CTA graduum tantum<br />

aginta. Vcrum ob mo-<br />

Terror, quo Sol, in confcquentia<br />

motu apparente<br />

kransfertur, Luna, priufquam *-.* .<br />

Solem afl-equitur , defcribit<br />

angulum CTa angulo re&o majorem in ratione t+qpQ+ rev?-<br />

lucronis Lunaris S@odic.z: ad tempus revolutionis PeGodlw ,HZ!<br />

eit, in ratione 29d~ 1.2,h, 4+!. ad, 2+;! b 7 !. 4$: Et hoc pa&o anguli<br />

omnes circa centrum 5F’ dilatantur in eadem ratione, 6r VakGat,io<br />

maxima qu;re f&us e&c 32’. 32”, jay a$$. in! G&km ratione<br />

fit: 3s’. IO”.<br />

kkc eit ejus magnit@q in medi0cr.i difllallti< Z$ljs. a. ‘T&r+(<br />

neglk&ig dif&entiis qua 2 cu:rvatura Orbis magni. rnaj;lriqqr: $0~<br />

iii aaione in Lunam falcatam. & noyam qum, in, grbbo&q &.<br />

&em&, oriri, p&nt. In. &is difia+tGs Solis a, Terja., Varia,tiq<br />

maxima efi ‘in ratione quz compckitur ex duplicata ratisne temr<br />

pork revolutionis Synod& Lunaris (data anni tempore) dir&e,<br />

g trip&+ ratignp di,fiantirx: Salis., ;! Terrainverfe, Jdeoque in,<br />

Apogaes


40s<br />

ariatio niaxima eft 33” 14”, & in ejus Peri@ tI B ER<br />

Eccentriciras Solis iic ad Orbis .magni fimidia- TEPTIU~am<br />

tranfverfam ut 16% ad IOOO.<br />

a&cnus Va:Gtionem invefiigavimvs in Orbe non eccentrico,<br />

in quo Utique Ijuna in OQantibus filis femper elt: in mediocri fiua<br />

~&+ntia a TeWa. Si Luna proper eccexrtricitatein fUaElj. magis<br />

ve:l minas- &Rat-. 2 Terra quati G lohetur in IWC Orbe; Vzhiatio<br />

na.ulo! l+jqajor CRC poteR vel paulo minor quam pro Regula hit<br />

gg&ata : Ced’ ~~~flirn ve’L d6fe&un$ ab Aitronomis p&r PhticrrneI~a<br />

~&e?min~ndum reliliquo.<br />

~~RC’FOSITIO XXX. FROBLEMA XI.<br />

Defignet- S Solem, T Terram, fip Lunam, J\I!P G Orbem Luns,<br />

zz veltigium Orbis in plano Eclipticae 5 I% zz Nodes, nZ”Nm


pi? &lip&x j a 4 Qsdraturas Lund in piano Eclipticz, k.2~<br />

MUNDI<br />

s YSTE hlAT E perpendiculum in lineam g4 Qadraturls interjacentem. vis<br />

Solis ad perturbandum motum Lun,?: (per Prop.xxv.) duplex efi,<br />

altera line% L M, altera linea MT proportionalis. Et Euna vi<br />

priore in Terram, pofieriore in Salem kcundum lineam re&xz $2<br />

a Terra ad Solem duti:a paralielam t~*ahitur. Vi’s prior’ LM<br />

agit: kcundum planurn orbis Lunaris, & propterea fiturn plani nil<br />

mutat. Hzc igitur negligenda efi. Vis pofierior MT qua planum<br />

Orbis Lunaris perturbatur eadem efi cum vi 3 T I( vel 3rJr.<br />

Et hax vis (per Prop, xxv.) eiP ad vim qua Luna in &MO circa<br />

Terram quiefcentem ‘ternpore fuo periodic0 uniformiter revollvi<br />

poffet, ut 3 IT ad Radium circuli multiplicatum per numerum<br />

178,725 five ut .TTad Radium multipticatum per f9,575. Gaterum<br />

in hoc calculo & eo omni qui fequitur, confiders lineas omnes<br />

a Luna ad Solem d&as tanquam parallelas line= qua a Terra<br />

ad Solem ducitur, propterca quod inclinatio tantum fere minuie.<br />

effehs omnes in aliquibus caiibusJ quantum auget in &is . &<br />

yadorum mqtus mediocres quarimus, neg!eBi+’ ifiitiftio’di 1 ,&$u-<br />

~UQ ~uaz,rcaloulum 1 nimi’s iinpeditm redckrenc, :’ ~ ,’’<br />

.‘-<br />

.,<br />

e-


RINCIPlA~ HEMATICA:; iv<br />

YIP 13 X A.27 proportionalis, & conjunfiis rationibus, P J{x ‘p N Lrocn<br />

lfk X T2, X AZ> & TK S.L$‘,& x,&Z uc TIRTI~~.<br />

d-i UT ConEeINUm<br />

.Kk x ‘p ‘21) X.&-Z 4~4. id elt, ut area F a~ do & AZ~‘/. conjun&&n.<br />

$i& 4% 22.<br />

Coral 2. Jn d ata quavis Nodorum pofirionc, motes horariuq<br />

mediwris cfi fernif’& m~f;uq horarii in. S.yzyGiis Lunz, jdeoquc CR<br />

Q $‘ &e”e 3 s”‘. z 6”. 3 6”. WC quadraturn Gnus difiantiz Nodorum a<br />

~yzpgiis ad cfWkatw Radii,, five ut ~‘Zqzt. ad AT& Naln<br />

%i &uw Wlifor~i c.Qm nn,of-u pcrambulet hnicircihy RAq, f~tm-<br />

43V WW/Um wwum T fD L#&?, quo Oqmrc Luna per@t a 2 ad<br />

-&4 Vk area gM dE qu3z ad circufi tangenrcm J&t’ termina-<br />

PLlr j & qU0 kempore Luna attingit punfium B, rumma i[la erit<br />

area tdta &! @A% quam linea.T’D defcribit, dein EUII~ pergente<br />

ab FZ ad 4, linea T CD cadet extra circnlum ,. & aream zq c ad<br />

circuli tangentem 4 e terminatam defcribets quzp quoniam Nodi<br />

prius regrediebantur, jam vero progrediunrrrr, fubdrrci debet de<br />

area yriore, lk cum atqualis fit are= $2&EN, relinquec knicirculum<br />

NgA12. lgitur Cumma omnium arearum ‘T‘D dik?, quo 1,<br />

tempore Luma femicirculum defcribit , eR area femicirculij &<br />

$“mma 0mniti.m quo ternpore Luna circulum dercribit efl area circuli<br />

tocius. At ‘area fp CD d 1w, ubi Luna verfarur in Syzygiis, e8t:<br />

re&angulum fub arcu fp iI?2 & radio MT j & fumma omnrum huic..<br />

azqualium arearum, quo tem>po.re Luna circuIum deccribit, ell:<br />

re&anguluem hb circumferencia tota & radio circull 3, & hoc<br />

re&anji$um , cum fit zquale duobus circulis, duplo majus eR<br />

quam re&angulum prius. Proin:de Nodi, ea cum velocitate uniformiter<br />

continuata quam habent in Syzygiis Lunaribus, i‘patium<br />

duplo majus defcriberent quam revera defcribunt; L;r propterea<br />

motus mediocris quocum, fi un:f3rmlter continuareCur, jYpatiUn1<br />

a fe &quabiIi cum motwrevera conk&urn dekribere poffent, efi<br />

.fernifis motus quem habent in Syzygiis Lonz~. Unde cuni motus<br />

horarius maximus, fi Nodi. In Qyadraturis verfintw fit,<br />

3f. lc/‘. 3 3”. I 2v, motus mediocris horarius in hoc cdu erit<br />

3 6”. 3 y. 16”. 3u. it hum motus horarius Nodorum femper fit<br />

Ut AZ~B. & area F 27 d M conjunaim, 2% propterea mow horarius<br />

N odorurn in Syzygiis Lunx: u,t Azql~. k area pa dM<br />

conjunEtim , id & (: ob &tam a.ream Fp’cZ,~d~ti in Syzygiis deccriptam)<br />

IJ~ n,Zqu, erit etiam motus mediocris~ut AZqw. atque<br />

zdeo h.ic mot.us, ubi. Nodi cxrra Qndratwaa verfintw wit ad<br />

-&g; .J f. z6tv. .p; ut &$jhp a.d’ATqs &&ES:<br />

P R 0..


hnenire m&m korarium Nodorum l&me in Orbe Ellipticn.<br />

.<br />

Defignet $i&p m d q Elliph 9 axe majore gq) minore ab dehiptam,<br />

R&q Circulum circumfcriptum, T Terram in utriufque<br />

ccntro communi, S Solem, p Lunam in Ellipfi motam, & pm arcum<br />

quem data temporis particula quam minima defcribit, AT & ti<br />

Nodes linea Nlz junfios, 9 K & rn,$ perpendicula in axem ,LQ<br />

demiffa & hint inde prod&a, donec occurrant Circulo in 9 &A&<br />

22<br />

ii’ ..I<br />

B<br />

,<br />

& linez +Jodorum in I) & d. Et fi Luna, radio ad Terram du-<br />

620, arcam defcribat ternpori proportionaIem, erit mows Nodi in<br />

‘EllipG ut area p “&) d m.<br />

Nam ii fB F rangat Circulum in T, & prod&a occurrat TN<br />

in F2 63s p/ rangat El1ipfi.n in p & produaa occurrat ,eidem TAT<br />

ius


PRIN’CPPI~ EMATICA. 409<br />

ifl ,J COnVeniant a~rem h tangences in axe Tg ad rj & G L,iR I: ii<br />

&fL defign!t fpati\lm quad kuna in Circulo revolyens, interea TcNT:~,<br />

dUm dekriblt arcum ‘P M, urgeme 8r: impcllellte vi prxcliQa<br />

3 ITS motu ,tranfverro dekribere p&T& & ml defigt,cc fpatium<br />

qtlod hna ln Ellipfi revolvens eodem [empore, ur&enre etiam vi<br />

3 IT9 dekribcre pofXet 5 &producant~r L T & Zp doncc occurrant:<br />

@ano EcIiptlcz in G Srg; 8-c<br />

junganrur FG & fg, quarum F’G<br />

produea f&et: Ph pg 8~ TRin c3 e 8s R refpe&ive, k fg prcsdu&a<br />

fecet T$( in r : Q,oniam vis. 3 1~ feu 3 pi in crrculo<br />

efi ad vim 3 JT 6~ 3p K in Ellipfi, ut 4p K ad p I


??E i\,fWNOl iterior proportionalis fit motui Nodorum in Circulo, erit area.<br />

sYS’I‘EblnT E prior proportionalis motui Nodorum in Ellipfi, ,$QE, 59.<br />

CowI. Igitur cum , in data Nodorum pofitione, fhnma omnium<br />

a~a~urn p ‘22 dr/, quo tempore Luna pergit a Qadratura ad locum<br />

qucrnvis m, iit area mp J&Z LI, quze ad Ellipkos tangentem,<br />

2.E terminatur j & fumma omnium arearum illarum, in revolutioue<br />

inregra, fit area ElIiptCos totius : mot-us mediocris Nodorum<br />

in ElIipfi erit ad motum mediocrem Nodorum in Grculo, ut EI-<br />

Iiplis ad Circulum 5 id eit, ut Td ad TA, ku 69 ad 70, Et<br />

propterea9 cum motus mcdiocris horarius Nodorurn in Circwlo<br />

lit ad 16’/. 3$‘T IQ”, 36”. ut AZqaJ. ad ATqu. fi capiatur augulus<br />

I 6”. 2 I”‘. 3% 3 ov, ad angulum I 6”. 3 5”‘. 16”. ~6’~ ut 69 ad go,<br />

crit mows mcdiocris horarius Nodorum in tilllpfi ad 16”. z I”/.<br />

siVe 20”. ut A.274 ad A Tq j hoc efi, UC quadraturn finus difiantix:<br />

No& ;I Sole ad quadratum Radii.<br />

Ckterum kuna, radio ad Terram du&o, aream velocius dekribit<br />

in Syzygiis quam in Qadraturis, & eo nomine tempus in Syaygiis<br />

contrahitur ) in Qadraturis producitur ; & una cum ternpore<br />

mows Nodorum augetur ac diminuitur. Erat autem momentum<br />

are2 in Qadraturiskunar: ad ejus momentum in Syaygiis<br />

ut 10973 ad 11073, & propterea momentum mediocre inO&antibus<br />

efi ad excefiml in Syzygiis, defe&umque in Quadraturis, ut<br />

paumerorum kmifilmma I 1023 ad eorundem femidifferentiam go,<br />

Unde cum tempus Lung in fmgulis Brbis particulis qualibus fit<br />

reciproce ut ipfius velocitas , erit tempus mediocre in O&antibus<br />

ad exccffim remporisin Qladraruris, ac defehm in Syzygiis, ab<br />

hat cauf~ oriundum, ut 11023 ad 50 quam proximc. ergendcb<br />

autem a Qladraturis ad Syzygias, invenio quad exccffus momentorum<br />

are33 in locis Gngulis, i‘upra i~~omcntum minimum in Quadl-aturis,<br />

fit ut quadraturn finus difiantiz %unz a Qadraturis<br />

3JUXIl groximc j & propterea differentia inter momentum in loco<br />

quosunque & momentum mediocre in Ohanribus, efi ut differentia<br />

inter quadratum finus diitantirt: Lunz a aadraturis &<br />

quadratum finus graduum 4f) feu femiirem quadrati<br />

incrementurn teqq7oris in loch hgulis inter O&antes &<br />

turas, & decrementurn ejus inter O&antes & Syzygias<br />

dem ratione. Lotus autem Nodorum, quo tempone<br />

currit hgulas Brbis particulas aquales, acceleratur velt<br />

in d uplicata rxtione temporis, Efi e11im WQtM$ iitep<br />

per-


CIPIA MA HEMATIC,A. 4’1<br />

yercurrit fp M, (cceteris par.ibus) ut ML, 8r: ML; elt in dupli- L~sK::,<br />

cata ra tione tern pork Quare morus Nodorum in Syzygiis, co TE~*~!c~<br />

tempore confe&:us ~LIO Luna daeas Orbis particulas pcrcurrit, di-.<br />

knuitur in dupkata ratione numeri I 1073 ad nwnerum I 1023 i<br />

efiquc dwrknentum ad motum reliquum ut IOO ad 10973, ad<br />

’ motu,rn vero totuxn Ilt IOO ad I: 1073 quam proxime. Decrementum<br />

auteln in lock inter O&antes & Syzygias, & incrementurn<br />

in locis inter O&antes 8-z Qndraturas, eft quam proxime ad<br />

%loc decrementurn, ut motus totus in locis illis ad mocum toturn<br />

in Syzygiis & differentia inter quadraturn bus difiantix Lun3e a,<br />

Qadratura &I fkmiffem quadrati Radii ad femiflem quadraci Raglii,<br />

conjun&tim. Unde ii Nodi in Quadraturis verfentur, & cagiantur<br />

loca duo zqualiter ab O&ante hint inde ditiantia, & aiia<br />

duo a Syzygia’ & Qadratura iifdem intervallis diktntia, deqw<br />

decrementis motuum in locis duobus inter Syzygiam & O&:antern,<br />

. Ikbducantur incrementa motuum in locis reliquis duobus, qw<br />

funt inter O&antem & Qadraruram ; decrementurn reliquum<br />

aequale erit decrement0 in Syzygia: uti rationem ineunti facik<br />

co1IRabit. Proindeque decrementum mediocre, quad de Nodorum<br />

motu mediocri fubduci debet, efi pars quarta decrementi in<br />

Syzygia. Motus’totus horarius Nodorum in Syzygiis (ubi Luna<br />

radio ad Terram du&o aream tempori proportionalem defcribere<br />

filpponebatur) ecat 32”. 42”‘. live Et decrementum mows Nodorum,<br />

quo tempore Luna jam velocior defcribit idem fpatrum,<br />

diximus effe ad ‘hunt motum ut IOO ad 11073 5 adeoque decrc-<br />

Pnentum illud efi 17”‘. 43iv, I ly, cujus pars quarta 4”‘. 2riv. 48”3<br />

motui horario mediocri iuperius inventq x6/‘. 21”‘. 3iy. 30”. Clbd&a,<br />

r&quit x6”. 16”‘, ~7~~. 4zv. motum mediocrem horariwm<br />

corre&um.<br />

Si Nodi verfintur extra Quadraturas, 8z Cpetientur loca bina a<br />

Syzygiis hint inde zqualiter difiantia; fimma motuum Nodorum,<br />

ubi Luna verfatur in his locis, erit ad hnmam motuum,<br />

ubi Luna in iifdem locis & Nodi in C&adraturis verfintur, ut<br />

AZgti. ad* ATqw: Et .decrementa* motuum, a .catifk jam expofitis<br />

oriu.nda, krunt ad inyicem, ut ipG mows, adeoque mows-r&-<br />

qui erunt ad invicem ut AZ+ ad ATqw.. SI: motus nlediocres<br />

u t mdttis. reliqui. Eit; itaque motus medlocrls hararius corre&us9<br />

$ d&o ‘qfidcunque Nodorum fitu,. ad 16”. 1,6”‘, 3,~“. 4~“~ ut,A,Zq~r;<br />

ad AT’g& j idefi, ut ‘quadraturn finus. diBantiae,Nodorum a Sy-<br />

s~ygiis ads qua$dtqn% Radii.<br />

~~~~iv<br />

P R or


kvsszire<br />

motum nzedium Nodorum<br />

Mom medius awnuus elt filmma motuum omniw-n hcsrariorum<br />

mediocrium in anno. Concipe Nodum verhri in AT9 & BinguIis<br />

horis completis retrahi in locum Gum priorem, WC non obfiante<br />

mote ho proprio, datum femper fervet ficum ad Stellas Fixas.<br />

Interea vero Solem & per mown Terra, progredi a Nodo, 6.~<br />

curfiim annuum appareneem uniformiter complere. Sit auccm<br />

An arcus datus quam minimus, quem re&a 275’ ad SoIem fkmper<br />

duea, interk&ione fui & circuli NAR data tempore quam mi-<br />

Gmo defcribit : 8~ motus horarius mediocris ( per jam ofienfi 1<br />

erit ut AZq, id efi (ob proportionnIes AZ ZT) UE retiangulum<br />

fib AZ & .ZT$ hoc e&, ut area AZTa. Et fumma omnium<br />

horariorum motuum mediocrium ab initio, ut fumma om..<br />

.gium arearum dTZ.4, id efi, ut area NAZ. Efi au.tem maxima<br />

‘dZ% zqualis r$kanguIo fub arcu Ad & radio circuli 3 62 propaerea<br />

fumma omnmm re&angulorum in circulo toto ad Summam<br />

totidem maximorum, ut area circuli totius ad rekmgulum fib<br />

circumferentia tota 8~ radio; id efi, ut H ad ;G. tus autem hoyarius,<br />

re&amgulo maxima refpondens, erat p: 6”. rl, 37”. 4av, Et<br />

hit motnsl arm toto Mereo dierum LJQ~, bar. 6. nzi;la. 9,. fit<br />

pg” 3 8’, a”0 joy’. deoquc hujus dimidium ~g@#.+$~ I’* ff’l’, efi motuf3


RINCIPTA MA E-~EJ&$-‘P”Ic/~, 4 1 3<br />

WIS medius Nodorum circulo ro reibondcns, Et morus Lvuijr,-<br />

rllma qLS0 tempore SOI pcrgit ab AT ad A, cii ad 19sr. +J+ s,~a ff’ /.<br />

ut area 2$+&Z ad circulum torum.<br />

kb2C iGt k habe~lta eX ~q’pOk’fi qyod Nodus horis ~i~~plt\iq ifa<br />

iocum~griorem rerrabitur, lk ut SoI anno tot0 comg]eto id sodim<br />

eundem redeat a quo Cub initio djgrc&s fL1.z1.3c, Vcruru per.<br />

lzlotum Nodi fit ut.Sol citius ad Nodum f’eVcrEGTI!r, Lk coi7,putanda<br />

jam efi abbreviatio, temporis. CtJ111. SO1 LlW110 [f.jre, c()ilfici;lr,<br />

360.gradus, & Nodus motu maxima eodem rcmporc ~~,!~~~~cret<br />

3.9 gr- 3 8’. 7”. p”‘, fku 39,6j 5 I gradUS j tk !IIOtllY mc;liocris Nodi<br />

ill IOCO quovis N fit ad ipfiuS motum mediocrem ill @L]adratur&<br />

ii& ut AZq ad A Tq : eric mows Solis ad mocum N7~s~~ ~7 ntj AX+,<br />

Unde ii circuli totius circumferwria i?Ldz divi&tur in p;lrtictl-<br />

1.2~s zquaIes Aa, rempus quo Sol percurrae parthAm A:r, ii circulus<br />

quiefceret , erit ad tempus quo percurric e:lndcm p;1rticulam,<br />

ii circulus una cum N,odis circa centrum I’ revol~atup,<br />

reciproce IX pjo827~4dAiP”q ad p,o~~7646A’Tq-+-AZ~. Narn<br />

tempus c& reciproce ut velocitas qua particuh pcrcurfitur, 8~<br />

hxc velocitas.efi filmma veiocicatum Solis 8-z Nodi. Igituc ii rempus,<br />

quo Sol abfque motu Nodi percurreret arcum A?A, cxponatur<br />

per Se&orem lVT,A, 8s particula temporis quo percurrercc.<br />

arcum quam minimum Act 3 exponarur per Secttoris p3rticuIsm<br />

era ja & (perpendiculo a T in. Ah demiffo) 9 in AZ cn~iarut<br />

&z, ejus longitudinis ut fit re&angulum dZ rn ZT ad SC&oris<br />

particulam ATLJ UC AZ q ad y,08~7WATq -I- AZq, id efi, LE<br />

fir dz ad t/Z ut ATg ad 9,0827G+6ATq++Zq; refiangu-<br />

]um dz in 2 J” defignabit decrementum ternporls ex motu-Nodi<br />

OriurldUm, tempore toto quo arcus Aa percurritur, EC ir yun-<br />

LIMII d tangit- Curvam NdGn3 area curvilinea hTdZ crit dccrcfllentunl<br />

tBtUm, quo tempore awus totUS .N A percurritur 5 k<br />

Ejropterea excegis Sekkoris NA T fiipra aream NfZ erlt tfJuYus.<br />

illud roturn. Et quo&m motus Nodl ternpore m,more*rflinor efi<br />

ill ratione temporig debebit etiam area AuTZ dmh~l HI eadem<br />

ratione. Id quad fiet-fi capiatur in AZ longitude e 2, qu:T I’nt<br />

ad long+-Jinem A,Zf it AZq -ad 9~os37~46$TqC~zC!* Sic<br />

enim reaangulum e,~ ia z 2” erle ad aream R .ATcc ut decremennum<br />

temperis quo arcus A! percurrlcw ad tempus t*tum q<br />

percurreretw fi Nodus quietberet : Et progcerea re@angulum ill<br />

zef!ond&it &cremcnto MOWS No&- ht fi pull&Llm c fangazl<br />

Curvam<br />

*


4 Ii!-& PI-4 P L N--L% NA33em.A~<br />

,313~ MUN~I Curvsm .NeFrz, area tota %\leZ, qua hmma eit omnium decree<br />

sycrE31nFr: mentorum, rcrpondebit decrement0 toti, quo tempore arcus AI+!”<br />

percurritur ; & area reliqua JIAe refpondebit motui r&quo, qui<br />

verus efi Nodi motus quo rtempore arcus totus IV-A, per Solis &<br />

Nodi conjuntios moms9 percurritur. yam vero area kmicirculi<br />

efi ad aream Figuraz Ne Fn IG per methodum Serierum infinitarum<br />

quafitam, UC 793 ad 60 quamproxime. Motus autem qui<br />

,refpondetCirculo tori erat 19g’* 49’. 3”. 55”‘; & propterea motus,<br />

qui Figurz Ne Pn I” duplicataz refpondet , eit: I gr* zp’. 58”. 2”‘.<br />

Qui de motu priore fiibduhs relinquit I 8 P xg’. 5”. 53”‘. motum<br />

torum Nodi inter fui ipfius Conjun&iones cum Sole; &I hit motus<br />

de Solis motu annuo graduum 360 hbdu&us, relinquit 341 grq<br />

40’. 54”. 7”‘. motum Solis inter eafdem Conjunfkiones. Ifie autern<br />

motus efi ad motum annuum 3609’. ut Nodi motus jam inventus<br />

I 8 gr* 13’. 5”. 53”‘. ad ipfius motum annuum, qui propterea<br />

erit Iper* IV. I”. 2 3”‘. Hit efi motus- medius Nodorum in anno<br />

Sidereo. Idem per Tabulas Afironomicas eft xp@ z I’. 21”. 50”‘~<br />

Differcntia minor eiE parte trecenteiima metus totius, & ab Orhis<br />

Lunaris Eccentricitate & Inclinacione ad planum Ecliptics<br />

oriri videtur. Per Eccentricitatem Orbis motws Nodorum ni.mis<br />

acceleratur, & per ejus Inclinationem vicifflm retardat’ur aliquan-<br />

.tulums & ad j&am velocitatem reducitur.<br />

.Fra,OP0SITIO XXXIII. I’l’K.lBLEMA XJV.<br />

Ijzveniye rnatum rwerum Nodorum<br />

In ternpore quod eit ut area .AZT&-.?fNdZ, (2~ .Eg.+pr~mA)<br />

;motus ifie efi ut area N&IV, & inde;d;itur. Yerum ob, nimiam,<br />

calculi difficulcatem, prazfiat Gquentem ProbIemaGs confiru&ior<br />

nem adhiberc. Gem-0 C, illtervallo qudvis CD, dakribatur<br />

circuluS B E FZI. Producatur DC ad A, UC fit A,B ad AC<br />

UC motus medius ad kmiffem motus veri mediocris, ubi Nodi<br />

fint in Quadraturk (id efi:, ut 19 P* 18’. I”. 23”‘. ad lpgr* 49’,.<br />

3”. 55”‘, atqw adco B C, ad AC ut. motuum differentia ogr. 3 I’..<br />

2”. 3 #I, ad motum pofieriorem I‘p’g’* 49. 3”. 55”‘) hoc efi, ut<br />

I! ad3 38?> dein per pun&m fz> ducatur infinita Ggi quz tangat<br />

circulum itI ‘D ; & ii capiatur a~?gulas BC E vel B,CfT xqualis<br />

&pla dihntk So.@ a loco HodI, per ,*motum medium inyento 3<br />

&


]PRRWN?IA MATHEMATIcA. klr<br />

zsc agatur AE vel AF fecans perpendiculum I) G in G; k ~a- L,I’L?P9<br />

piatur angulus qui fit fd motum totum Nodi inter ipfi\\sSvzy- *~‘i 2.~: i<br />

gias (id efi, ad 9 gr* I I . 3”,) ur rang ens ‘D G ad circuli B ‘E; SD<br />

circnmferentiam eotam ; atque anguhs il3ic (pro quo angtilrrs’;DAG<br />

ufilrpari pot&) ad motum medium Nodorurn addntur ubi No&,<br />

t<br />

wanfeunt a @@raturis ad Syzygias, & ab eodem rnotu me&o<br />

tibducatur ubi tranfeunt a Syzygiis ad Qyadraturas 4 habcbitur<br />

” .<br />

eorum motus verus. Nam motus verus ilc lnvcntus congruca:<br />

quam proxime cuti motu vero qui prodit exponendo tenlpus per<br />

aream NTA---NdZ & motum Nodi per aream NAenJ; ut<br />

rem perpendenti & computationes infiituenti confiabit. Hac e&<br />

aquatio annua motus Nodorum. Efi ‘2% azquatio menftrua, fed<br />

quz ad inwntionem Latitudinis Lunx minime neceffaria 4. Nam<br />

cum Variatio lnclinationis Orbis Lunaris ad planum Ecliptic= du=+<br />

plici inxqualitati obnoxia fit, alteri annu;rz, alteri autem menarug;<br />

hujti”s menfirua inzqualiras & squatlo menfirua Nodorum<br />

ita fe mutuo contemperant & corrigunr, ut ambaz in determinanda<br />

Latitudine Lunar neghgi pofint.<br />

CaroX Ex hat Sr: prazcedente Propofitione liquet quad Nodi in<br />

Syzy#3 fuis quiefiunt, in QuPadraturis autem regrediuntur matu<br />

h&rat-i0 r6”. rg”‘, 26’y. Et- quod aequatio motus Nodorum in<br />

Q&antibus fit I grk ~9’~ Q3z omnia cuzn Shzenomenis cceleltibus<br />

probe quadrant.


8t: a Syzygias; R& g Qadraturas; N bk FI<br />

um in Orbe fuo; p veRigiutn loci illius in p<br />

Ecliptics 9 6.~ mapI motum momentaneum Nodorum ut Cwpra.<br />

Et fi ad lineam T RZ demittatur perpendiculum T G, jungatur p GT,<br />

& producarur ea d ec occurrat T n g, & jungatur etiam Tg :<br />

crit angulus T Gp clinatio -orbis naris ad planum Ecli,pticq<br />

tibi Lun~verfatur in.T; ‘8~ angulus Tgp Inclinatio ejufdem ]pofi<br />

,momentum temporis completum; adeoque angulus G T Variatio<br />

.momentanea Inclinationis. Efi autem hit ang$us G 5! g ad angulum<br />

G Tg, UC TG ad T G & T/J ad T G conJun&im. Et propterea<br />

fi pro moment0 temporis fubfiituatur hors; cum angulus<br />

G 2-g &per Rro.poiic, xxx, ) ct ad angulum 33”. _r$ ,33”. ut


MATMEMATICA.<br />

PRINCIPI<br />

4.17<br />

IT% T G x A % ad A’ ?kb 3 wit anguhls G?Pg (ku Inclinationis<br />

horaria Variatio) ad angu~um 3,“. Lo”‘. 33iv, ut JT~AZ~ TG! ~“;,ie:T,~.<br />

x ;$ ad A T-c&. A&E I.<br />

E&-a ita k haha ex Hypothcfi quad Luna in Orbe Circulari<br />

uniformiter gyratur. cod fi Orbis ille Ellipticus fit, motws me-,<br />

diocris Nodorum mhuetur in ratione axis mmoris ad axem tnajo..<br />

rtm j uti fiipra expoficum efi. Et in eadem ratione minuctur<br />

etiam ~nclinationis Variario.<br />

CMU~. I. si ad NY erigatur pcrpendiculurn TF, iitque PM<br />

mocus horarius Lunz 1-n ylano ~clipticx ; & ;perpendicula PI


418 PI~IeosorwrA NATURALIS<br />

‘l)~. MUN DI efi (cum pp fit ad T G ut iinus khnationis pxzdi&k ad ra-<br />

SYSTENATE<br />

dium, & AZxT2<br />

:&42-<br />

fit ad 4 AT ut Gnus duplicari anguli AT@<br />

ad radium quadruplicatum) ut Enclinationis ejufdem finus dutiu~<br />

in finurn duplicate dittantke Nodorum a Sole, ad quadrupium<br />

quadratum radii.<br />

Curol. 4, Qoniam Inclinationis horaria Variario, ubi Nsdi in<br />

Qadraturis verOn tur , efi ( per hanc Propofitionem ) ad angu-<br />

Tp<br />

fum 33”. 10”‘. 33’:’ ut ITxAZXTGX~~~ ad ATcab. id cfi)<br />

Ut rTCl-GXTp<br />

m ad 2 AT; hoc efi, ut finus duplicate di-<br />

*-AT<br />

2<br />

fiantiz Lunz 3 Qadraturis d&us in 6Px<br />

fpP<br />

ad radium duplica-<br />

tUm : fUmMa Onlnillm VariarionLlm hOrariarUn~, Cj,UO fefflpore<br />

Luna in hoc firu Nodorum tranfit ?t Qadratura ad Syzygiam,<br />

(id efi, fppatio horarum 177:~) wit ad fiummam rotidem angulorunl<br />

33’! IO”‘. 33i”, ku 987b”, ut iilmma omnium finuum duplicats<br />

difiantia Lunz. j Qgadraturis du&a in<br />

TP ad iummam to-<br />

3%<br />

cidem diamctrorum j hoc elt, ut diameter d&a in FG<br />

w<br />

ad cir-<br />

cumferentiam j id elt, ii Inclinatio Gt 5gr* r’, ut 7 X& ad 2~~<br />

i‘cu 278 ad 10000. Proindeque Variatio tota, ex fumma omopium<br />

horariarum Variationum tempore prazdi&o conflata ) em<br />

m63”, ku 3’. 43”.<br />

PROPOSITIO XXX-V. PROBLEMA X-W.<br />

Sit AZ) finus Znclinationis maxima, & BB finus %nclinatio.-<br />

nis minim%. Bifecetur BZ) in C, & centro C, intervalIa BC,<br />

deicribatur Circulus BGD. In AC capiatur CE in ea ratioge<br />

ad E B quam E B habet ad 2 @A: Et ii dato temyore canfiiwatur<br />

angulus A’ E G zqualis’ duplicate difiantk Modorgm A<br />

a-


emx.INCIPIA MATHEMATIC,A. 4x9<br />

adraturis 9 & ad AZI demittatur perpendiculum G H: erit g ‘R‘ I,rn ? FC’ .,<br />

orfl N iinus lncIinationis quaAita2.<br />

Nam GEg azquale eft GHq+NEg=BH~+r-IEqr--<br />

XlTD2)-;N~q--Rq==~‘i)t~Eq--2~Hx6’E-<br />

BEq -)-zECxBH==;rECxAB+ 2ECxBH=~ECxA.M<br />

Pdeoque cum 2 EC detur, efi GE 4 ut AH. DeGgnet jam A’Eg<br />

duplicatam diftantiam Nodorum 2 Qadraturis pelt datum allquad<br />

momentum temporis complecum, 6s arcus Gg, ob datzlm<br />

A<br />

k-------<br />

angulum G Eg, crit ut difiantia GE. Efi autem Hh ad Gg<br />

w G H ad GC, 6~ propterzHHb efi ut contentum GHx Gg,<br />

GH<br />

i&u G Hx G E, id ei), ut rE%GEq fell rE~AH, id cfi,<br />

ut AH & finds anguli AE G conjunO%~. Tgitur fi AN in<br />

cafu aliquo fit finus Inclinationis 9 augebitur ea iifdem incrementis<br />

cum Gnu lnclinationis, per Corol. 3, Propofitionis fuperioris,<br />

& propterea finui illi zqualis femper manebir. Sed AH ubi<br />

pun&urn G incidit in pun6tum alterutrum B vel D huic finui<br />

aequalis elt, & propterea eidem fkmper azqualis maner. &E.ZI.<br />

In hat demonftratione fuppofui angulum BEG, qui eft duplicata<br />

difiantia Nodorum h Qadraturis, uniformiter augeri.<br />

Nam omnes inaqualiratmm minurias expendere non vacat. L’oncipe<br />

jam angufum BEG retium efi, & in hoc cafii Gg eire<br />

augmenturn horarium dupla: difiantisl: Nodorum & Solis ab invie<br />

02117 ; & Inclinatignis Variatio lwraria; in ederr, sati (per Coral.<br />

3. Prop. noviffh~:) erit ad 33’. Ed”, 33”. ut wnrentum filb Inclinationis<br />

finu AN Sr finu aaguli re&i BE G, qui eit duplicata<br />

&&antia Nodorum a Sole, ad quadruplum quadratum radii;<br />

id ert, ut mediocris Inclinationis finus AN ad radium quadrupliatum<br />

j hoc efi (cum Xnclinatio illa .mediocris fit quail 5 gr* 8’:)<br />

ut +s finus ‘896 ad radrum quadrupkatum +oooo, five ut 224<br />

ad 10003. ER autem Variatio tota, finuum differentk BZ,<br />

refpondens, ad Variationem illam horariam ut diameter Bfz) ad<br />

Whh 2 arcum


420 PHILOSOP~-~I~ NATURALIs<br />

DE M~NDI<br />

arcum Gg ; id efi, ut diameter B 23 ad femicircumferenriam<br />

SysTEh’ATe BG~) st tempus horarum zo7pIz0, quo Nodus pergit i l&a&aturis<br />

ad Syzysias, ad horam unam corljun&im; hoc efi, ut 7 ad<br />

11 & 2073,‘~ ad 1. C&are fi rationes omnes conjungantur, fret<br />

Vari;tio rota BD ad 33”. IO"', 3~~” ut 224X 7X 2073;'~ ad<br />

.X IOOOO~ id efi, UC .zp6+5 ad 1000, Sr inde Variatio illa Bf,D<br />

prodibit 16’. 3: 3”:.<br />

Hat efi lnclinationis Variatio maxima qwatenus locus Luna in<br />

Qrbe ho non confideraw. &Tarn Inclinatio, G Nodi. in Syzygiis<br />

verfinrur, nil mutatur ex vario fitu Lunz At ii Nodi in C&adraturis<br />

confifiunts Inclinatio minor efi ubi Lunna verGtur in Syzygiis,<br />

quam ubi ea verfatur in C&adraturis, exceffi 2’. 43”; uti<br />

in Propofitionis fuperioris Corollario quart0 indicavimus. it<br />

hujus exceffus dimidio 1’. 2 1”;. Variacio tota medlocris B 9 in 1<br />

Qlladraturis Lunaribus diminuta fit 15'~ z", in ipfius autem Syzygiis<br />

au&a fit 17’. 45”. Si Luna igitur in Syzygiis confiituatur,<br />

Qariatio tota, in tranfiru Nodorum A Quadraturis ad Syzygias,<br />

,erit 17’, 45”: adeoque fi lnclinatio , ubi Nodi in Syzygiis verfanfur,<br />

fit $er* 17’. 20’; eadem, ubi Nodi funt in aadraturis, &<br />

Luna in Syzygiis, erit 4gr* 59’. 3$‘# Atque kc ita k habere<br />

confirmatur ex Qbkrvationibus.<br />

Si jam defi+retur Orbis lnclinatio illa, ubi Luna in Syzygiis<br />

& Nod1 ubrvls vcrfantur ; fiat Ai ad AZ) ut finus graduum<br />

59’. 35” ad finum graduum 5. 17’. 20”~ & capiatur angulus A.E<br />

zqualis duplicataz difiantiz Nodorwm A Q_uadraturis; & erit A fl<br />

Gnus Inclinationis quazfitz Huic Orbis Inclinationi zqaalis efe<br />

ejuC&m Inclinatio, ubi Luna difiat po gr- ,i Nodis. In &is Lunz<br />

locis inkqualitas menfirua, quam lnclinationis variatio admittit,<br />

in calculo Latitudinis Luna: comyenhtur & quodammodo tollitur<br />

per inaqualitatem men&warn .motusNodorum, (ut di7lprr-e diximus)<br />

adeoque in calculo Latitudinis illius negligi gotefi.


Hike motwlm Lunarium computation&us Oflen&re vala,;<br />

gUo$ ITlOtUS Lunares, per Theoriam Gravitatis, a cnui;s li,js c.,Ii.”<br />

putari pofht. Per eandm 2’heoriam ~IIVCXC p-,?-,terea q1114Lj i.pquatio<br />

Annua medii motw Lun3e oriatur a Varl;l ~]llatac,orje (;)rbii<br />

Lunar per vim Solis, juxra CoroI, 6. P~-op, Lx171, Lib, 1, ~1,~~<br />

+iS in Perigzo Solis major cfi, & @rbem Lunrl: dllarat; i!l ~~~~~<br />

gX0 ejus minor Cl?, & Orbem illum corltrahi pcrfuictit. in ();.bC<br />

dllatato Luna tardius revolvitur, in contra&o citius; k ,+qu;ltio<br />

Annua per quam hzc inazquahtas compenfatur , ia ~~~~~~ ‘Q<br />

Perigzo Solis nulla efi, in mediocri Soils a Terra diltantia ac1[<br />

I I’. 50” circiter akendit , in aliis locis AZquationi cctltri SolIs<br />

proportionalis eit, & additur medio motui Lunze ubi. Terra pergit<br />

ab Aphelia fi~o ad Perihelium, & in oppofita Orbis partc iilbducitur.<br />

Aflkmendo radium Orbis magni 1000 tk Ecccncpicitatern<br />

Terra 16;, hxc 2Equatio ubi maxima eIt, per Thcoriam Gravitatis<br />

pr.o,diit II! 49”. Sed Eccentricitas Terra2 pad0 major tile<br />

videtur, & au&a Eccentricitate hzec Bquatio augeri de&c in e:~dem<br />

ratione, Sit Eccentricitas 16$$ ) 8c &quatio maxima erlt<br />

I I’. 52/c<br />

lnveni e&m quad in Perihelia Terra, propter majorem vim<br />

Sol&, Apogxum &Nodi Lunzc velocius nyventur quam in Aphelie<br />

ejus, idque in triplicata ratione difiantla: Terra a Sole inverk<br />

Et inde oriuntur mquationes A~IIUCEZ horum motuum Equationi<br />

centri Solis proportionales. R/lotus autem Solis efi in duplicata<br />

ratione difiantig Terraz a Sole inverk, & mlfxim? centri.1Equatir<br />

quam hat inaqualitas generat, eit: I grw 56. 26 qrzdl&F Soils<br />

Eccentricitati 16% congruens. Qod fi motus Sobs eifec rn trlplicata<br />

rat&me difiantiz iye;& hzc inaequalitas generaret &quarionem<br />

rnaximam ZY 56’ 9 Et proprer.ea Bquationes maxi-<br />

•<br />

m= quas inxquaEtates motuum Apogzi & Nodorum Lund generant,<br />

funt ad z gr’ 56’. 9!,<br />

nt motus medius diurnus Apogsi &<br />

motus me&us diurnus Nodorum Lunz. funt ad motum .-medium<br />

diurnum Solis.<br />

wnde pro&t JEquac~o maxlma medll motus<br />

.&ogaei 19’. 52”: & J$uacio maxima medri motus Nodorum<br />

9’. 27”.<br />

Additur vero &quatio prior 8f fubducitur POiferiUra Ubi<br />

yyerra pergit a P&h&o fuo ad Aphellum : 8~ contrarlum fit. ln<br />

~gp~fita -Orbis parteb<br />

Per


4. L z ~q-t-I~Lgl)sBBHI~ NATURALIS<br />

I, II 51 II !’n1 Pet *Theoriam Gravitatis conltitit etiam quad aQio Solis in<br />

(3 ~;~rE~I~T* Lunanl paulo major iit ubi tranfverfa diameter Brbis Lunaris<br />

t.t.allfir per Solem, quarn ubi endem ad re&os efi angulos. cum<br />

linea ‘Terram & Solem jungencc: & propterea Orbis ~vqs<br />

paulo mnjur efi in priore c;lfii qu3m in pofieriore. Et hlllc ori:<br />

cur alia .2q\latio mows medii Lunaris, pendens a fitu Apogal<br />

Lund ad Solem, qw quidem maxima e(t cum Apog~um Lund<br />

verfacur 111 Oftante cum Sole; &C nulla cum illud ad Qpdraturas<br />

vcl Syzygias pervenit : & motui media additur in tranfitu Apagazi<br />

Luna a Solis Qtladratura ad Syzygiam, & fubducitur in tranfiru<br />

Apogxi a Syzygia ad Q_uadraturam. HZ &quat@ qwam<br />

Semeltrem vocabo, in O&antibus Apogxi quando maxima efi,<br />

alendit ad 3’. 45” circiter, quantum ex Phanomenia colhgerc<br />

potui. Hsc elt ejus quantiras in mediocri Solis difiantia a Terra.<br />

Augerur vero ZIG diminuitur in triplicata ratione difiantia: Solis<br />

Inverfe, adeoqne in maxima Solis diitantia efi 3’. 3+“, & in minima<br />

3’. 56” quamproxime: ubi vero Apogzum L,una fiturn eit<br />

extra


RPNC‘l[PIA MATHEMATIcA.<br />

425<br />

7, 8 & ga Prop. LXVX. Lb. 1. Et 1132 inqualitatcs per cad& Ltarat<br />

Corollaria perrnagoz fun t, & LEquationem principafefll Apog:~i T i c T !q:‘:<br />

geveranrS quam Semefirem vocabo, EC 14Equatio maxima semefirIS<br />

eR 12 gr* 18’ circiter, quantum ex CIblErvationibus colligere<br />

&?otni., H~roxz’r~ nofier Lunam in Ellipfi circwm Terram, in ejus<br />

~zrnbilkx.3 inferiore confiituram, revolvi primus fiaruir. Hdfkss<br />

ccntrum Ellipfios in Epicydo locavit, cujus centrum unifornlicer<br />

revolvitur ciseum Terram. Et ex mote in EpicycIo oriuntur inazqualitates<br />

jam di&tar: in pcogreffu & regrcff‘u Apogxi & qua-iagate<br />

Eccentricitatis. Dividi intelligatur diitantia mediocris Euntr:<br />

a Terra in partes xooooo, & referat 2 Terram & TC Eccencric&tern<br />

mediocrem I;unz partium 55o5. Producatur TC ad B,<br />

ut fit CB fitius ~&quationis maxim8 Semeltris i 2 61. 18’ ad r:\-<br />

di.um TC, & circulus B DA centro C intervallo CB dekriptus,<br />

erit Epicgclus. ille in quo centrum Orbis Lunaris locatur & k-<br />

cudurn. ordinem Xiwarum B DA revolvitur, Capiatur angulus<br />

$3 GD zqualis duplo, argumento annuor fku dupln dikmtk veri<br />

loci $Gi ab Apogazo Lunx: Femel zquato, St erit CT23 Aquaria


DE. 31~~~1 liciti annui prxdi&i Cupra difiantiam Apogzi Luau a ]Perig~~<br />

“” ’“‘.“I” Solis in conf’cqucntin; vel quad perinde ett, capiacur angulus<br />

CD F xqualis complemento Anomaliz verg Solis ad gradus 360~<br />

Et iit 211; ad ZI C UC dupla Eccentricitas Orbis magni ad dirtan-<br />

;-riarn mediocrem Solis a Terra, & mows medius diurnus Solis ab<br />

~pog~o Lund ad motum medium diurnum Solis ab,, Apo$;;<br />

.proprio conjunQim, id efi, ut 33; ad IOQO St yz’, 27 . 1.6<br />

59’. 8”. 10’~ conjunLXm, five ut 3 ad 100, Et concipe cenrrum<br />

.Qrbis LUIIX locari in pun&o F, & in Epicycle cujus cenrrum elt<br />

I) ~31 radius ‘%> E interea revolvi dum pun&urn D progredirur<br />

in circumferentia circuli 2) AB 2). Hat enim ratione velocieas<br />

.qua centrum Orbis Luna in linea quadam curva circum centrum<br />

C defcripta movebitur, erit reciproce ut cubus difiantiaz Solis a<br />

Terra quamproxime, ut oportec.<br />

Gompuratio mows hujus difficilis efi, kd facilior reddetur per<br />

approximationem fequenrem. Si difiantia rnediocris Lun;e a Terra<br />

iit partiurn ~ocooo, & Eccentricitas TC fit par&m 5509 ut fu-<br />

-pra: retta CB vel CZ, invenietur partium r172& & re&a 92-F<br />

B<br />

‘partium ‘3 5;. Et hzec~re&a ad difiantiam TC fiibtcndit ~ngul~~rn<br />

.ad Terram quem tranflatio centri Orbis a loco B ad locum %’ ge-<br />

-nerat in moru centri hujus: 6r eadem re&a duplicata in fitu parallelo<br />

ad difiantiam kperioris umbilici Orbis Luna a Terra 3 fubtendit<br />

eundem angulum, quem utique tranflatio illa gcnerat in motu<br />

.umbitici, & ad difiantiam Lung a Terra fubtendit angulum quem<br />

teadem tranflatio generat in motu Lunar, quiquelpropterea &quatio<br />

centri Secunda dici potek Et hzc Bquatio in mediocri Lutz<br />

difiantia a Terra; efi ut Gnus anguli quem re&a illa 2) F cum re&a<br />

a pun&o I; ad Lunam du&a continet quamproxime, Sr ubi maxima<br />

elE evadit z’:z5”. Angulus autem quem re&a ZlF & re&a<br />

a..pun&o P ad Lunam duQa compreh,endunt, invenitur vkl fibducendo<br />

angulum ED F ab‘ Anomalia media Lunar, vel addend0<br />

+diitantiam Lunz a Sole ad difiantiam Apogzi Lw~a ala AP;x~;


L_<br />

ma hujus quarei proportionalis & anguli cujufdam alterius @-ad<br />

Variationeln Secundam, CLlbducendam fi Lunx lwnen augetur, addendam<br />

ii diminuitur. Sic habebicur locus verw Lunx in Orbe,<br />

& per Rcdutiionem loci hujus ad Eclipticam habebitur Longifudo<br />

Lun= Anguli vero P & Qcx Obkrvationibus deccrminandi<br />

Clint, Et interea G pro angulo P ufirpentur 2’, & pro<br />

angulo Q x ‘, non multum errabitur.<br />

~LIlll Atmofphrera Terra: ad ufque altitudinem milliarium 37<br />

vcl 40 refringat lucem SOliS & refringendo Cpargat eandem in<br />

Umbram Terrs9 & lpargendo lucem in confinio Umbra dilatat<br />

U&ram :<br />

ad &metrum Umbrae quz per ,Parallaxim prodit,<br />

addo lninutum unum primurn in Eclipfibus hflat, Vd millUtUIII<br />

mm cum triente.<br />

Theoria vero Lunli: prima in Syzygiisj deinde in Qac+~uris,<br />

& ult,imo in OQantibus per Phanotiena exapman .& flablhrr debet,<br />

Et opus hocce aggreKurus motus m;edlos Soils St Lunz ad<br />

rempus meridianurn in Obkrvatorio Reglo Grfnayzcenfi, die ulq$no<br />

me&s 5%cernbris anni 1700. it. vet. ~OII lncomyodq, fequenfes<br />

ad hibebit : nempe motum medium Soils. W. 2~” 43 • 40 J &<br />

Apogzi ejus b 7gr*:$411*,j$~’ ‘8~:&qctim. .medrum Luna z I 56’.<br />

_ ,‘, 00”~ & ,Ap~gil’ eJUS” 3-C ” 8 gr* 20 .( OF “, :‘ 8t‘ Nodi afcendentis<br />

2C<br />

CT’ 24,: 20’ j 82: cM?erentiam :mendlanoium Obfervatorii IIU-<br />

Q =7<br />

j.u, & Obfer=&Xii Regii Tarz@%fif ~~~~~ prnin* jOGc’.<br />

r* I(: -,i ,A’


$26 PHILQSOPHIA<br />

NATURALIS<br />

DE MtJNDI<br />

3 ‘ii T L :,I AT E<br />

PROPOSITIQ<br />

XXXVI.<br />

PROBLEMA<br />

XVII.<br />

Mtwe wozlendum.<br />

Solis vis 31L ku TIT, in @uadraturis Lunaribus, ad perturbandos<br />

mows Lunares, erat (per Prop. XXV. lwjus) ad vim<br />

gravitatis spud nosl ut 1 ad 638ogz,6. Et vis Z-&?-L 21/1 f’eu<br />

2 ‘P K in Syzygiis Lunaribus, eit duplo major. Wx autem vires,<br />

5 dekendatur ad hperficicm Terra, diminuuntur in ratione dihnciarum<br />

a centro Terry, id efi, in ratione 60: ad I j adeoqtlc<br />

vis prior in fkperficie Terra, efi ad vim gravitatis, u 1 ad<br />

386o+Goo. Hat vi Mare deprimitur in lock qua: go gradlbus difianr<br />

s<br />

a Sole, Vi alcera qu;l: dupIo major efi, Mare elevatur & fub Sole<br />

& in regione Soli oppofita. Summa virium efi ad vim gravitatis<br />

ut I ad 12868200. Et quoniam vis eadem eundem tier motum,<br />

five ea deprimat Aquam tin ,regionibus quit: 90 gradibus difiant B<br />

Sole, five elevet eandem in regionibus fhb Sole & Soli oppoiitis,<br />

hzc fumma erit tota Soiis vis ad Mare agitandum; & eundem<br />

habebit efFeEtum ac fi rota in regionibus hub Sole & Soli oppofitis<br />

&lare elevaret, in regionibus auteikl guz 99, grad&us difiant<br />

a Sole nil ageret.<br />

Hat efi vis Solis ad Mare ciendum in loco iq,ovis da;to,. &,:&al<br />

tam in vertice loci verlatur quam in mcdipcri fua ‘difta&iCa<br />

Terra. la $iis Solis pofitionibus vis ad Matie attol!&du& &<br />

UC finus verfus dupla: altitudinis Solis rupra horizontem loci &<br />

re&e & cubus difiantiti Solis a Terra inverfe.<br />

&rol. Cum vis centrifuga partium ‘T’errz 2 diurnoTerra motu<br />

Oriunda, quae efi ad vim gravitath ut z ad 289, eficiat ut altitudo<br />

P


lpdo ALE fub Bquatore fuperet ejus altitudinem Tub PoIis ieli-<br />

Lrtlrn<br />

fk-a pedum Parificnhm 8f820 j vis Solaris de qua egimus, cum TE”nT:tI.<br />

fit ad vim gravitatis ut I ad 12868200, grqtle adeo ad vim illam<br />

centrifugam ut z6p ad 12868200 ieu I ad 4452~~ efficier ut altitudo<br />

Aqua in regionibus &lb Sole & Soli oppofitis, fiipcret alritudinem<br />

ejus in locis quz po gradibus difiant a Sole, menfura<br />

tantum pedis unius ParifienGs & digitorum undecim cum o&avs<br />

parte digiti. Efi enim hat menfira ad menham pedurn gj810<br />

ut I ad 44527.<br />

A27<br />

PRoPOsIa:IO XXXVII. PROBLEMA XVIII.<br />

vis Lunz ad Mare movendum coliigenda cfi ex cjus proportione<br />

ad vim Solis, & haze proporrio colligenda cfi ex propor-<br />

Cone motuum Maris, qui ab his viribus oriuntur. Ante ofiium<br />

fiuvii AUOPZ~ ad lapidem tertium infra BrdJZo&znz, ternpore verllo<br />

8~ autumnali totus Aquas. afienfus in Conjunbne & Oppofitione<br />

Luminarium (obfervante &~mueZe 6’ttiunaio) & pedum ~1~s mi-<br />

IIUS 45, in Quadraturis autem eR pedum tantum 25. Al&do<br />

prior ex fumma virium, pofierior ex earundem differentia oritwr.<br />

Solis igitur & Luna in Bquatore verfantium &C mediocriter a<br />

Terra’ difiantium finto vires S & LJ & erit L +-S ad L-S UC<br />

4~ ad 2ps i’eu 3 ad 5*<br />

In portu T&+zutbi &itus maris (ex obfhvatione Samuelis Cokpr&)<br />

ad pedes plus minus fkxdectm altltudine mediocri attolli-<br />

,cur, ac tempore verno & autumnal1 altrtudo AEfius in Syzygiis fu-<br />

.perarc pot& al titudinem ejus in Quadraturis, pedibus plus feprem<br />

vel o&o. Si maxima harum altitudinum differentia fit pedum novem,<br />

erit L + S ad L-S ut 20; ad 1 I$ feey 4~ ad 23. QJXE<br />

proportio fatis congruit cum p.riorc. Ob magnrtudinem JW.H in<br />

por tu Bijfdiic, obfirvationisbus JYtirtPcii magls fidendum eire VI=<br />

detur, ideoque donec aliquid certius confiiterit, proportionem 9<br />

r UCurpabimus.<br />

-‘-dEterurn ob aquarum reciprocos motus, ~%fius ma$mi non in-<br />

&i&nt *in i fas Luminarium !Syzyglas, fed ,funt tertla a $3 zy@ig<br />

it di@kum P suit, lfeu ,proximc fequuntur tertlum Lu,na: po x .Sy~y~<br />

@as appulfum ‘ad meridi*anum loci, ye1 potius .(ut*,a. $‘WWJ~U no0<br />

;tatur] funt tertii p& diem novllunlr vel plcnrh~n~, &%I pofi boo<br />

- 1 Xii 3 barn


De MUNDI ram a Ilovi[unio vel plenilunio plus minus duodecimam, adeoquc<br />

SySTE’l”TF. jnc;dLlll~ ill horam a novilunio vcl pknilunio plus minus quadram<br />

gefimdm tertiam. Inci?unt vefo in hoc portu in horam feptimam<br />

circiter ab appulfi~ Lum ad. meridianurn loci; ideoque proximc<br />

f~quuntur appulhm LLIKC ad meridianwm, ubi Luna difiat a<br />

Sole vel ab oppofitione Solis gradibus plus minus o&odecim vel<br />

novelldccim in confequentia. f4Xitas & Wyems maxime vigent,<br />

non in ipfis Solfiitiis, fed ubi Sol difiat a Soliiitiis decima circiter<br />

partc totius circuitus, ku gradibus plus minus 36 vcl 37. Et<br />

fimi]itcr maximus ,%fius m,rris oritur ab appulh Euna ,ad meridiaaum<br />

locis ubi Luna difiat a Sole decima circiter parte motus<br />

totius ab AlWu ad &fium. Sit difiantia illa graduum plus minus<br />

T 8:. us: vis Solis in hat dill-antia Lilnz a Syzygiis & C&adratmris><br />

minor erit ad augendum & ad minuendum motum mai-is<br />

a vi Lung oriundum, quam in ipfis Syzggiis Sr Qadraturis, in<br />

ratiolIe radii ad hum complementi diitantlz hujus duplicate: ku<br />

wguli graduum 37, hoc eft, itI ratione. ~ooooooo ad ygfj6355.<br />

Ideoque in analogia fuperiore pro S fcribl d&et 0~79863 55 S.<br />

Sed & vis Lunar in C@adraturis, ob declinationem Lunx ab<br />

Aquatore, diminui debet. Nam Luna in Quadraturis, vel potius<br />

in gradu l8$ pofi aadraturas, in declinatione graduuih plus<br />

minus 22. 13’ verfatur. IEt Luminaris ab Bquatore declinantis<br />

vis ad Mare movendum diminuitur in duplicata ratione finws<br />

complemenri declinationis quamproxime. Et proprerea vis<br />

Lunx: in his C$adraturis efi tan&Urn 0~8570327 L. Efi igitul:<br />

L5;40,7986355s ad 0,857Q327L-O,7986355s ut p ad 5.<br />

Prxterea diamerri Orbis in CJ,LIO Luna abfque Eccentricitate mod<br />

xeri deberet , funt ad invicem ut 69 ad 70 3 ideoque difiantia<br />

Lunar ‘iTerra in Syaygiis efi ad,difitintiam ejws in Quadraturis,<br />

ut 69 ad 70, cxteris par&us. Et difhtiz ejus in gradu 1~8t a<br />

Syzygiis ubi Bitus maximus generatur, & in gradu 182 a (&adracuris<br />

ubi AMus minimus gencratur, fht ad mediocrem ejus<br />

dihntiam, UC 69,0&47 & Gg3y734s ad 69:. Vires autem ,,I&<br />

BE ad Mare movendum hnt in tri,plicata satione dicantiarum inverfi,<br />

ideoque vires in maxima & minima harum diitantiarum funa;<br />

advimin mediocri difiantia, ut Oj9830427 & 1p17F.22 ad,I. Wnde fit<br />

x,oq5~2L4-0,79~~3~55 S ad 0,983~4~7~0~~57~3~7~-0,798~35~~$<br />

w 4 ad f. Et S ad L ut I ad 4,48.r 5. ltaque cum vis Sol&, fit<br />

ad vim gravitatis ut: I ad 12868200, vis Luna: erit ad vim gravirabis<br />

ut x ad 2.8~~&Xh<br />

G9roL


PCdk unius 2% undccim digitorum cum oQava Parte djgitj, eadelll ‘~~RTIUS..<br />

vi LLIXC afiendet ad altitudinem o&o pedum & digitorum oao,<br />

c3Z vi UCCI~UC ad altitudinem Pedum decem cum remink, & ubi<br />

LWI~ efI in Perigao ad aititudinem Pedum duodecim cL1411 cemiG&,<br />

& llitf% ~r&X~im Llbi &ff US ventis fPirantibus adjuvarl1.r. TaIlta<br />

atJtCM V~S ad OMUCS Maris motus excitandos abu~~de [Llficit, p&,<br />

quancitari motuu~l~ probe reljpondet. Nam in maribus quz ab,<br />

Chicllrc in Ckcidcntcm late patent, uti in P&u-i ~.gc;fica, & blaris.<br />

.&ZUYtth+Zi & &?tha’upka’ partibus extra TroPicos, .aqua actol\i row<br />

let ad nltirudinem pedum fex 3 novem, duodecim vel quindecim.<br />

3n Mari ~LICCIII ‘Y’nc$‘~o, quad Profundius efi 8~ latius Patet, &fius.<br />

dicuntur etk majorcs quam in AtZ68ntico.& &thiopico, Erellinl<br />

LN phus tit &ltus, latitude Maris ab Oriente in Occideljtem non<br />

minor efk debec qu;im gr~duum,.nonaginta. In Mari c,.&zhiopico,<br />

afcenflls aqu;l: intra Tropicus Qlrllor efi quam in Zonis tempera-.<br />

tis, propter *angufiiam Maris inter /Ifricam & Aufiralem yartem<br />

Amwic~. In media Mari aqua nequit akendere, nifi ad liteus<br />

utrurnque & orientale & occidentale fimal defcendat : cum tamen<br />

vicibus alternie ad littora illa in Maribus noitris angufiis deikew<br />

dere debeat. Ea de cauh fluxus & refluxus in InG.k, qu3: F<br />

littoribus lon#$ne abfwt, perexiguus e@t .@et. 111 Portubus<br />

guibukhrn, ubi aquiz cum impetu yagno per’ Joca vadofi, ad<br />

Sinus altcrnis vicjbus implendos pi: evacuandop, inflyre &~efBuere<br />

cogitur, flux~is & refluxus debellt effe iblito maJores3 uti ad<br />

CjJ@ygdtbg1;92 & pontem Cb?~~ow& i~~~Az@a j- a$ montes S. lk!.h<br />

f-&e&f & Ltrbelyy, Ahkwut~~oyz~7fl (vulgs Az4rdn+es)., in NOrinnrG 5<br />

ad’ c,&&&~~yw; & f13egti in ,hzdk ori~nta~i~ Evils fn @is mares<br />

magna culn velacitate accedendo EL rccc$endo,~ htcora nunc in-,<br />

undat ~URC arida relinquit ad nnllta mihria. Neque impetus<br />

influendi, & remealldi prius frangi pgtefi, quam aqua attohur<br />

VC] deprimitur .ad pqdes 3+ 403 Wk 50 .!% amPlius* Et. par” Ffi<br />

ratio rrctorum ObJongorut‘n & vadofo;rum,, -.u ti~~~g-f~~~zf~~ & ejus<br />

~L;Q ~~g$& circuudatur. I@fius.in hujufmsdi: portu bus & ..frecis,<br />

per innpceum eurcus & recurris fupra modum augetur, Ad littora<br />

vero qw dekenfu prx+prtl a!, mare profundum & apertum<br />

+eaanr,, ubj aq~a fine. lmpetu e&!endi. & remyndi aFto!li &<br />

i’ubfidkre pot@ 2<br />

n!agultlada, ,JlZAu~ : reCpor&t vlnbus Sob ,&<br />

JAmiE. -: ’ ;<br />

COd,


$38 ‘PHIrr,osorI-II~ E9ATWRBLIS<br />

nE hfl!X’Dl Covol, 2. Cum vis Lunxz ad Mare movendum, fit ad vim gravis~-ST?:,l.\‘r’r<br />

fatis UC I ad zfj71.j.00, per$icuum efi quad vis illa iit longe<br />

rnlnor qu:~m ~IIX vel in experimentis Pendulorum, vcl in Staticis<br />

aut Hyyd’rofiacicis quibukunque kentiri poflit, In &flX fOl0 marho<br />

h;cc vis knfibilem edit efkiitum.<br />

CGPDI. 3. Quoniam vis Lunz ad Mare movcnd\lnI, clt ad Solis<br />

Ivim confimilem ut 4,481~ ad 1, & vires illz ( per coral. l+e<br />

Prop. LXVI. Lib. 1.) funt ut denfitatcs corporutn Lunz 6E So@<br />

& cubi diametrorum apparcntium conjwnBim j denfitas LU~X erl[:<br />

ad denfitatem Solis, LX 4>4815 ad I dire&e & cubus dlayletrr<br />

Lunra: ad cubum diametri Solis inverk: id eft (cum diametr;, mediocres<br />

apparentes Lunre & Solis fint 31’. 16$” & 32’. 12 ) ut<br />

48pn ad 1000. Denfitas autem Solis erat ad denfitatem Terra><br />

UC 100 ad 396; & propterea denfitas Lunze eft ad denfitatem<br />

Terrxt ut 4.891 ad 3960 fiu 2 I ad I 7. Efi igitur corps LU~XX<br />

denfius & magis terreflre quam Terra nofira,<br />

Co~ol, + Et cum vera diameter Lunar ( ex Obfervationibus<br />

Atironomicis) fit ad veram diametrum Terra, ut IOO ad 36g;<br />

erit mafia Luna ad rnaffam Terrae, UC I ad 39,371,<br />

Coral. 7, Et gravitas acceleratrix in fuperficie Lunz, erit quail<br />

triplo minor quam gravitas accelcratrix in fuperficie Terrze.<br />

Carol, 6. Et difiantia centri Lunz a cencro Terra, erit ad diitantiam<br />

centri Luna a communi graviratis centroTerrle & Lunar,<br />

UE 40,371 ad 39,371.<br />

Coral. 7. Et mediocris difiantia centri Lunz a centroTerrz, erie<br />

,femidiarne trorurn maximarum Terra 695 quamproxime. Nam<br />

kmidiameter maxima Terra fuit pedum farifienfium 19767630,<br />

& mediocris difiantia centrorum Terra & Luna ex hujufiodi<br />

femidiametris 60: conftans, zqualis efi pedibus 11poppp707. Et<br />

hzc difiantia (per Corollarium fuperius) efi ad difiantiam cencri<br />

Lunz a comniuni gravitatis centro Terra & LUIW, ut 40,371 ad<br />

3~~571, qua proinde efi pedum 1161498340. Et cym Luna rev<br />

volvatur refpc&u Fixarum, diebus 27, horis 7 & minutes primis 435;<br />

.fmus verfus anguli quem Lwna, tempore minuti unius primi. motu<br />

fuo media, circa commune gravitatis centrum Terra: 82 Luna: de-<br />

.fcribit, efi 127~23~, exifiente radio loof, oooouo, oooooo, Et ut<br />

radius ef? ad hunt finum verfim, ita tint pecks I 16~498340 ad<br />

.pedes x4,811833. Luna igirur vi illa qua .retinetur in Orbe, cadendo<br />

in Terram, tempore minuti unius primi defc.ribet .pedeQ;<br />

,14$1.2833. EC ii hzc sis augeatur in ratione r77$5 a.d x78$+, habe<br />

bit ur


RINCIIWi .~~ATPIEMATICA,<br />

Al? _<br />

+eb-itu,r yis rota gravitativ in Orbe Lung, per coral, pi++ .; iI,<br />

i,l!‘iFF.<br />

Et haC V1 Luna cadendo, tempore minuti unius primi defcr~bcrc T,::!-: :, :<br />

&beret pedes z4,8sg 17~ Et ad kxagefimam parcem llujus di..<br />

hntix, id efi, ad dlfiantiam pedum 19849995 a centro -rerrr,<br />

corpus grave cadendo, tempore mitluti unius fecundi defcribere<br />

deberet etiam pedcs 14,895 17. Diminuacur hsc diitalltia in cubduplicata<br />

ratione pedum 14~89517 ad pedes I 5,12028, &: /labcbitur<br />

difiantia pedum 197oI678 .a qua grave cadendo, codem rempore<br />

minuti unius kcundi defccnbet pedes I 5,12028, id efi, pcdes r5,<br />

dig. I, Iin. ~,31. Et hat vi gravia cadunt in hperficie crerl*x, ill<br />

Latitudine urbis h~etk TurzQ%rw~, ut fupra oftenhll cl+. EQ<br />

autcm difiantia pedum 1370r678 paulo lninor quam fcmidialllcter<br />

globi huic Terra zqualis, & pauto major quam Terra hujus<br />

,femldiameter mediocris, ut oportet. Sed di,fkrentis fiint inienfibiles.<br />

Et propterea vis qua Luna rerinetur in Orbe ho, ad diitantiam<br />

maximarum Terrze femidiametrorum 603, ea eft quam<br />

vis Gravitatis in fuperficie Terra: requirit.<br />

Coral. 8. Difiantia mediocris centrorumTerra: & Luna, eR mediocrium<br />

Terrae $midiametrorum 60: quamproxime. Nam kc<br />

lllidiamcter mediocris, quz. erac pedum 19688725, eCt ad kmidiametrllrn<br />

maximam pedum 19767630~ UC 60: ad 60: quam-<br />

-prgxime. ”<br />

3 * 1~ (,,,hi,s caf+uta~ionibus Attra&i&wn. magneticam ,‘Terra: non<br />

col&Jeravimus, cr,ljus u,ti:gue quant$as perpqrva efi & ignoratur.<br />

‘SiiGando ‘yero h&c Accra&b jnvefbgari poterit, & menfurx: &rf?-<br />

duum in Meridiano, ac longitudines Vendulorum ifochronorum ln<br />

~-.di~q&s ptir~fleli~~~ lef$fquo ‘m*d‘tutim Maris, & p+aIlaxis kin32<br />

:,cum ,diametriq +parentibus $dia .&.banz .ex Phzlenomenis accuratius.<br />

dgtegminataz fueri’nt : licebit calcuhm hunt. omnem accura-<br />

tius<br />

repeke+.<br />

:. .


Carol. hde vero fit ut eadem fernper Lunz kcies in Terram<br />

* obvertacUr. In alio e0im ficu corpus Lunare quiehre non poten,<br />

kd ad hunt fiturn okillando kmpcr redibit. Attamen okilhtiones,<br />

ob parviratem virium agitantium, eirenc long& tardiflimze:<br />

-:tdeo ut facies illa, qu;r: Terram kmper refpicere deberet, poffit<br />

alterurn orbis Lurks umbilicum, ob rationem in Prop. xvlt. all;a-<br />

.ram refpicere, ncque fiacim abinde retrahi & in Terram converri.<br />

L E M R4 A<br />

I[.<br />

Nam centro C diametro B Zl .d&zribatur fimici&lus<br />

.BAF’Z, C. Dividi intelligatur ;Temicircu’mFerentia BAD in<br />

partes


NC<br />

431<br />

p ar te s im-uneras 23ples 9 8c a partibus finguiis F ad diame- ~~~~~~<br />

trum ~?3 I) demittantur finvs P2’I Et fiimma quadratorum ex Tr.llTil:cfinibus<br />

omnibus .FT xqualis erit fummx quadratorum ex fin&us<br />

(omnibus CT, & f umma utraque zqualis erie fumma: quadratorun3<br />

CX tiotidem hni$iametris CF; adeoque fim3ma quadraton.xn~<br />

ex omnibus PT, wit: duplo minor quam fuumma quadrato-<br />

IW~I ex totidem femidiametris CF.<br />

Jam dividatur perimeter circuli .&E in particufas totidem a+<br />

8~ ab earum unaquaque F ad planum RR demirtatur<br />

rpendiculum FG, ut 8~ a pw@o A perpendiculum A&?. Et<br />

vis qua articula F recedit a piano Q.., erit ut perpe?dxulum<br />

illud F 8 per hypothefin, & hxc vis du&a in diftanelam CG,<br />

erit efficacia particula: F ad Terram circum ,centrum eJus convertendam.<br />

Adsaque efficacia particuk in loco FS erit ad efk<br />

~ caciam articula: in lock A, ut FGx G C ad AH% HC, hoe<br />

\ efi, ut P Cq ad AC 5 & propterea efficacia tota particularum<br />

mnium in lock fui$ P erit ad efficaciam particularurn totidem in<br />

oco A3 ut Cumma ony&rn FCq ad fu,pmam totidem AC@ hoc<br />

efi, (per jam demonfiraca) uf u_nuwm ad duo. J&E&?*<br />

Et quoniam particuk agune recedendo pefpendlculariter a<br />

plan0 g.R, idque zqualiter ab utraque parte huJus plani: eaderre<br />

* c$xgp&$xa~tisn cirouti Bquatoris, eiquk inh=enrem<br />

seffl tam in pkiio ill0 RR quam in pl@o c@qua~


DE MUNDI<br />

SYSTEMATE<br />

IL, E, M hd A II.<br />

Sit cnim PK circulus quilibet minor Aquatori AE p%.kllelus,<br />

hque L, I parriculx du32 qwvis zquales in hoc circuIo extra<br />

globum 2Qp c fita5 EC fi in planum &YJ?., quod .radio in Solem<br />

dufko perpendiculare efi, demittantur perpendicula L M, Im:<br />

vires totx quibus particulz ilk fugiunt planum RR, proportionales<br />

erune perpendiculis illis LA& Zm. Sit autem re&a Le’<br />

piano Tape parallela & bikcetur eadem in X, & per punw<br />

auy X agatur ,Nl;c, quaz parallela fit plano RR & perpendi-<br />

eulis L iM, Isn occurrat in N ac 72, & in plarlum<br />

satuf perpendiculum XT. Et parti&larum L &<br />

trarix , ad Terram in contrarias partes rotandam, rung ilt<br />

LM%MC & LmXmC, hocefi, UC LN%MC+ATNXMC &<br />

InXmC~nm)(mCj ~uLNXMC+NM~MC& EA?XmC<br />

-=$lmf


TMEMAT1c.A. 435<br />

--j?J2LTnd~mC: Sr harum difkrentia LiVx&‘m-JQfifx ~\~c+~,J~(‘, L~IJE~:<br />

efi vis particularurn ’ ambarum iimul fumpcarum ad Ter~t112<br />

T :: E ? I LB 5 ,<br />

~0ta?am Hujus diff‘erencix prs afirmativn 1, fvx Jfp? iii.1<br />

2 I, NY. XX, efi ad parcicularum dnJrum ejufdem m;lgnirudinis<br />

in A confifientium vim 2 A./ix tic’, ut LXq ad AC i;“.<br />

Et pars negativa A?MX ML + Yt2 C f3.l 2 XTX C T’, ad pnrrr--<br />

cuiwum eartmdem in A’ codifientium vim 2 A’NX ,r~lc:, LC<br />

cXq ad ACy. Ac proinde partium diffcrentia, id cfi, particu’larum<br />

duarum L Sr I hul i‘umptarum vis ad Terram r’otar!-<br />

dam:, em ad vim particularum duarum iifddem zqualium & in ]oc(p<br />

A confifientium, ad Terram itidem rorandam, ut I, Xq - CSy<br />

ad ACq. Sed fi circuli II! circumferentia dK dividatur i;l pJrticulas<br />

innumeras zquales L, erunt omnes L Xg ad totidem ISq<br />

ur E ad z, ( per Lem. I.) atque ad rotidem ACq, ut .IXq ad<br />

zACq; & totidem CXq ad totidem ACq ue zc’Xq ad 2~175.7~<br />

@are vires conjuntiaz particularum omnium in circu~W circdl<br />

IK, funt ad vires conjun&as przrcicularum totidem in loco A, ut<br />

1X2-- 2 CXq ad z ACq : & propterca ( per Lem. I.) ad vires<br />

conjun&as parcicularum roridem in circuitu circuli AE, ut<br />

IXq--tCXq ad ACq.<br />

Jam vero ii Spharaz diameter Tp dividatur in partes innumeras<br />

sequales, quibus i&&ant: circuli eotidem IKj materia in perimetro<br />

circuli cujufque II< erit ut IXq: ideoque vis mater&<br />

illius ad Terram rotandam, erit ut IXq in IXq- 2 CXq. Et<br />

vis mater& ejufdem, fi in circuli AE perimetro confifiteret, Get<br />

ut 1x2 in ACq. Et propterea vis particularurn omnium mater&<br />

tot&, extra globum in perimetris circulorum omnium confifientis,<br />

efi ad vim particularum totidem in perimecro circu!i<br />

maximi AE confifientis, ut omnia JXq in IXq- zCXq ad<br />

totidem IXq in ACq, hoc cl%, ut omnia ACq -CXq in<br />

~Cq-3CiYq ad cotidem AC’q-CXq in ACq,. id eR,” ut<br />

omnia ~~qq-4AC~xCXq-t-3CX~q ad totIde Ad=q,q<br />

--ACq xCXq, hoc eit, ‘.ut tota quantltas fluens. CUJUS fluxio<br />

efi AC~~-L~~AC~XCX~+~CX~~, ad totam quantitatem fluenrem<br />

cujus fluxi eff ACqq-AC xCXq; ac promde per Methodum<br />

Fluxionum, UC ACq Xc % -$~CqxeXG%~t~CX~C<br />

ad ACqqxCX -;ACqx C 4r CZ& id efi, ii pro CX fcribarur<br />

tora Cp vel AC9 ut fj ACq c ad $ ACq G> hoc efi, ut duo ad<br />

inque, $& E. “P,<br />

kk z LEMMA


DE MIJNDX<br />

SYSTEhSATE<br />

L E M M A III.<br />

ff enim motus Cylindri circum axem fuum immotum revol-<br />

~entis, ad mot-urn Sphara2 infcriptz & fimul revolventis, ut qua3<br />

libet quatuor zqualia quadrata ad tres ex circuiis iibi infcriptis:<br />

& motus Cylindri ad motum annuli renuifimi, Sphazram & Cyfindrum<br />

ad communem eorum contaCturn ambientis, ut duplum<br />

mater& in Cylindro ad triplum materice in annul0 j & annuli<br />

motus iite circum axem Cylindri uniformiter continuatus, ad<br />

ejufdem morum uniformem circum diametrum propriam, eodem<br />

rempore periodic0 faCturn, ut circumferentia circuli ad duplum<br />

diametri.


n/lotus mcdiocris horarius Nodorum Lunx in Orbe circulari<br />

ubi Nodi funt in Qqadraturis, eras 16”. 3 5”‘. 10. 3~. e,- hujui<br />

dimidium 8”. .17”‘. 38”. 15”. (ob rationes Cupra explicatas) elf ITIotus<br />

medius horaxius Nodorum in tali Orbe; fitque anno tolo<br />

Gdereo 2 oer- I I’. 46”. Quokml igicur Nodi Lunn: in cali orbe<br />

conficerent knuatim 20@* 1 I’. 46”. in antecedentia i (r; fi p[ljrcs<br />

effent L~7a-z motus Nodorum Cujufque, per eorol. 16. Prop.<br />

LXVI. Lib. 1, faretlr ut tern-pow periodica ; fi Lunq +ati(j<br />

,diei iiderci juxta kpcrficiem Terra revolverecw-, motus arinuut<br />

ISodorum fwet ad 20 gr* ,X I’. 4~2”~ ut dies fidereuq horarym 23, 56’.<br />

ad tempus periodicurn Luw dierum ~7~ 7 bar. 43’1 Id efi, UC<br />

1436 ad 39343. Et par elE ratio Nodorwy wxluli Lynarum<br />

‘I’erram ambientis; five Lund iIIa fk mutuo non contingant, five<br />

iiquefcant & in annulwm continuum formeneur, live dcnique annulus<br />

ilk rig&at & -inflexibilis reddatur.<br />

Fingamus igitvr qqod annulus ifie, quaad ,qnantitatem mat~r&~<br />

aqualis fk Terra otini I? G!p AT .e$ E qu%. gbabo P&p e fllp!Xlor<br />

ait,j,(~~d. gig. pa? 434,) & .quoniam.glQbus IRE & ad Terram illam<br />

fup.~rioore’m cl.mL-+, ad ACp ..T-dqu. .id e:D (cum Tcrr~ dkne~<br />

minor fp% vel aC fit ad diametrum majorem AC ut 3~ +d $30,)<br />

~lt 52441 ad +fpi G annulPs ifie Terr;ym kcundum r;Equatarem<br />

&g.erct & uterque iimul circa diametrp!n annuli reyolvereryr,<br />

gnpfus anggli @%qc ac! wWM gIObi i!PiOrJs (p? hU’~S ~~f!W<br />

ut 4I’ig ad 5+24-&I’.& ?oowo* ,ad pzjzyc kokajun. 65 l,rn? hoc efl,<br />

tit 4,530 ad 485223; ideoque motu’s annuifi &et ad-fimmam ma-.<br />

$gJl_i. g&g$Qb& uy ,J$&w Ad &?t&$- m%&,.fi.snnuls4s &-<br />

eat, &c&Otll&l $&$%I .sQMQ &$W A%$?& 4% P!JPGka .&SW!-<br />

noaialia regrediuntur, cum glob0 commumcet : mow qui reOabit<br />

in annul0 erit ad ipfius motum priofen, >t, 4590. a! 4898x3 i<br />

& prop!erGa Dotus pun!ZItorum BqulnoEtlallum dlmnuecur ip<br />

~&3pn f&one. &it igitur motus annuus puntkorum f%qurno&ialium<br />

corporis ex annul0 & glob0 compofiti, ad motum<br />

20 K”.


4-G HfLO%OPFlf& PYA<br />

DC hlu::1,r 3og” II’. &‘, Lit I.&# ad 393$.3 e,- L&pps ad ‘&813 COrnjilIl~<br />

*yus’rr51,tTi: ll-t.ifu~ id elt ut 100 nd 2!,3363. F,Ti~es atibetn quibus Nodi Lunarum<br />

(rlt ;ilpra cxplicui) :IrqGc adeo quibus pu~iLI:a &quinoc”rl3-<br />

11n annUli regrcdiuntur (id el1 vires 3 12; iW I;i;rT.pflg,4..03 SC L&O+)<br />

iilnc in iillgulis particulis ut dillaalciz2 parricularum ,i pIaIl L&R><br />

& lnis viribus particulz ills pianum hgiwit; 6-z propcerea ( per<br />

Lcm. %a.) li macerin annuli per totam, globi fuperficiem:, in mo-<br />

~-en7 figurx ‘d>np A Y3 ep Ej nd hpcrlore~~~ illdm Terrx parten<br />

confiituendam i~ar,gerctur, ITis Lk &cacla tota parricularum OIIInium<br />

ad Tcrf’3m circa quamvis 1 %quatoris diametrurn rorandam,<br />

;;tque tldco ad movcnda punQa J~quinotiialia, evaderet minor<br />

qum prlus in htione z ad 5, ldeoque annuw .AquinoLkiorum<br />

r-egreths jam effet ad zogr* IX’. 46”, ut PO ad 73092: ac proinde<br />

herer 3”. 5(j”‘. 5cP.<br />

Cxterum hit morus, ob inclinationem plani Aquatoris ad planun]<br />

Ecliptics, minuendus eit, idque in ratione Gnus pn706 (qui<br />

Gnus cil complementi graduum 23:) ad Radium ‘IOOOOO, Qa<br />

ratione motus iite jam fiet 3”. 7”‘. 20~‘. Hzc efi annua Prazcefio<br />

ACquinoQiorum a vi Solis oriunda.<br />

Vis autem Lunz. ad Mare movendum erat ad vim Solis, ut<br />

,+,4815 ad I circirer. Et vis Luna ad ASquinoQia movenda, efi<br />

ad vim Solis in eadem proportione. lndeque prodit annua AZuino&iorum<br />

Praxeff~o a vi hnrr: oriunda 40”~ 52”‘. 52”; ac tota<br />

racefio annua a vi ucraque oriunda 50”. 00”‘. x2’“. Et hit mow<br />

tus cum Ph3znomenis congruit. Nam Frzecefio &quino&iorum<br />

cx Obfervationi bus Afironomicis eit minutorum kcundorum plu$<br />

minus quinquaginta.<br />

Si altitudo Terra ad Bquatorem hperet altitwdinem ejus ad<br />

oloss milliaribus pluribus quam 175, materia ejus rarior a-it a$<br />

circumferen ti uarn ad centrum : et Prmceff~o JEquinoOkxu~<br />

ob altitudinem illam auger& ob raritatem diminui debet.<br />

Deferipfi~us jam Syfiema Solis, Terra, Lunz, & Planetarum:<br />

Cupwelt: ut de $hmetis nonnulla adjicianrur.


445 P PHI/E NATURALIS<br />

E


IN’CIPI A P-IEhIn*TrI@‘~,<br />

“j 4% I<br />

$dem colljgitur ex curvatura vk comc~arL,m. ~~~~~~~~~~ Ij4,.2: : ,,<br />

@q?ora propemodam in circulis maximis quarndiu ITIOVC;:rtL,r cclC- ..I<br />

rius j at in fine cLlrfi% ubi motus apparelltis pars ill;1 qu;r ;! rhkdkk<br />

oritw majorem habet proportionem 3d lilotun3, totuin .(_<br />

parentem, defle&ere ibknt ab his circulis, k quoties ~~~~~~ &-<br />

vetur in unam partem, abire in pat-tern concr;lriam, Ol’ifW i1.x<br />

deflexio maxime ex Parallaxi, progterca quad rcJ@ndcr rrlr,ltzl<br />

Terr;xl j 6.C infignis ej,s quantitas, me0 coin~3ut0, colloca$tit Jiji;,,<br />

renres Cometas fdtis louge infra Jovem. Unde conkqucns CG<br />

quad in Perigzis & Periheliis, ubi propills aJKll]t, del~cii~l!r:%<br />

Gzpius infra orbes Harris 8-c inferiorurn PIalletarum.<br />

Gz&%matur etiam propinquitas Cometarum es hcc caDiaLalzl.<br />

Nam corporis cceleitis a Sole illuhyri & in regiones ~~~~~~~~~~~~~<br />

abeuntis, diminuitur fpIendcr in quadruplicata ratione diltanri;c :<br />

Jn duptlieata ratione videlicet ob auAam corporis difla~~e&~n a<br />

Sole, & in alia duplicaea racione ob diminutatn diametram appxrentem.<br />

Unde fi detur & lucis quantitas & apparelIs diamctcr<br />

CIometazs dabitur difiantia, dicendo quod difiantia fit ad difirmtn-<br />

Cam Planeta, in ratione diametri ad diametrum dire& & rarione.<br />

Cubduplicata his ad lucem inverk Sic minima capillitii Cometa:<br />

anni 168% diameter, per Tubum opticum kxdecim pedum<br />

a .FZamJze& obkrvata & Micrometro menfurata, squabat 2j. Q”.<br />

Nucleus autefn feu fi&a in medio capitis vI’x decimam partem $-<br />

udinis hujus occupabat, adeoque lata erat tantum I 1”’ vel IZ -<br />

uce‘vero & claritate capitis fuperabat caput Comew anni 168~<br />

fiellarque prima vel fecunda magnitudinis arnulabatur. I’onamus<br />

~aturnum cum annul0 fro quail quadruple lucidiorem f’uifl‘e: 6E<br />

quoniam lux annuli propemodum zquabat luce,,m globi imer-<br />

,Jmedii) & diameter apparens globi fit quail 21 3 adeoque 1~<br />

lobi & annuli conjun&im zquaret hem glob& CU)KS diameter<br />

t 305 erit d&&a Cometae ad diftantiam Saturn1 UC I ad J-6<br />

hverk, & 12” ad 30 I’ dire&e, id efh ut 24 ad 30 ku + ad P<br />

s Cometa anni 166~ men&? /?)9rih, ut autl?or $ ~~*~e~~~~J,<br />

te fua pene Fixas omnes fuperabat, puf”etlam tpfum Saturmum,<br />

ratione coloris videlicet: longe vividrorlss Qupp(c Bucidior<br />

lerat hie Cometa alter0 iilo3 qui in 6~8: anni prgcedencls apparuexat<br />

& cum aellis prima: magnitudmls conferebatur, Laticudo<br />

capillitii erat qua6 6’3 at nucleus cum Planetis ope Tubi opcici<br />

51: nunc minor corpore inrermeco&g,~s~<br />

plane minor erat JOY<br />

11<br />

‘..-<br />

dis


%]:~a: c?i[pLrtavimus non coniidcrando ob~~uratiorrem Cometarum<br />

per fUJXLt~l1 il]UllJ J?laXlJlle CO~~Ofil~ll & CCZlihblfll~ quo Caput:<br />

~,irc~~lld~tLlt-q qd pcs nubem obtllk hemper lt.lSenS. IYam quanto<br />

obFcilriu:+ rcddirur corpus per IIUJIC hmum, tatlto propius ad<br />

~c..%~JII ~~edat nesefliz efi, ut copia lucis a fe reflexa Planetas 33-i-w<br />

lecur. lijde veridimile fit Comeras longe<br />

defkendere, uti ex Parallaxi vero quam maxime<br />

confirmatur ex Caudis.<br />

per &thera, vel ex 1Uce ca<br />

efi diffnntia Cometarum 9<br />

mper ortus per<br />

fpatin nimis ampla insredibili cum velocitate & expanfione pro-.<br />

gagecur, In pofieriore referenda eiE lux omnis tam caudaz quam<br />

capillitii ad nusleum capitis. IIgitur fi concipiamus lucem hane<br />

omnem congregari & intra d&cum nuclei coarLtari, nucleus i]lc<br />

jam certe, quoties caudam naaximam & fu1gentifhmu-n emittir,<br />

Jovem iphm fpplendore fuuo multum fiiperabir.<br />

cum diametro apparenre plus Iucis emittens, mu<br />

bitur a Sole, adeoque erir Soli multo propior.<br />

hb Sale delitekensias & caudas cum maximas<br />

inftar trabium iSnitarum noflnu~~q~~arn emittentia, eodem argumento<br />

infra orbem Veneris collosari debent. PJam lux illa om .<br />

fi in lItellam congregari Cupponaturs ipfam enerem ne dica<br />

nercs plures conywQas quandoque fuperaret,<br />

dem denique colligitur ex he capitum crekente in. rece<br />

ometarum a Terra Solem verb, ac decrekente in co<br />

Sole verfus Terram, Sic enim Comeja pofierior<br />

Cobkrvanse .Hev~Zio9) ex quo confpici cceyitJ ~~~~~~~~~~~~~~~<br />

de


de ~110tu fro apyaren@ adeoque prztericrat perigx~ltl~ j ~p~cl~s I. :;3/ :I<br />

&x VerO capitis nillilominus indies crefcebat, u{‘jue dum ~~~~~~~~~~~ -: fh 1 :<br />

radiis Solaribus obte&us deliit apprere. COlllCta Anni 1 C;l;j 1<br />

ob-kvmte eodem Hewelio, in fine cents ,yrl/;i ubi pri,l?um uc‘I1,l ._<br />

fPe&uS efit, tardiGne movehatur, nlinuta pritlla +a vcl -by Cit”ecemnb. 26.<br />

velocirlme motus, inque Perigzo . propemodum exiitens, ccdcht<br />

ori PegaG, Stek tertia: magnitudrnis. JLZKZ. 3. apparebac ut Stelh<br />

quartz:, Jan, p, ut SteIIa qurnta, gaGI I 3. ob fplendoren? @u,~<br />

crefceutis difparuit. JUG* 2 p vix aquabat Stelias magnrtudmrs<br />

ceptimg. Si fumautur aquaha a Perig3eo hint inde tempera, capita<br />

quae temporibus illis in longinquis regionibus pofita, ob<br />

zquales a Terra difiantias, zqualiter here dcbulOht , in plaga<br />

solis maxime fplenduere , ex altera Perigai parre evnnuere. Igitur<br />

ex magua lucis in utroque fitu difEere:ltia, concluditur magna<br />

Nxm<br />

1UX Cometarur)l<br />

regulars


444<br />

De MUNDI re~ularis effe folet) & 122axinna apparere ubi capita velociGme<br />

moventur, atque adeo funr in PerigXis j nifi quatenus ea major<br />

eit in vicinia Solis.<br />

TYSTE~IATE<br />

&VXJL I. Splendent<br />

igitur Comecz lute Solis a k reflexa.<br />

Caral. 2. Ex &&is etiam intelligitur cur Comet32 tantopere fiequentant<br />

regionem Solis, Si cernerentur in regionibus longe<br />

ultra Saturnurn, deberent kpius apparere in partibus Soli oppofitis.<br />

Forent enim Terra viciniores qui in his partibus vercarentur,<br />

c&z Sol interpofitus obkuraret csteros. Verum percurrend0<br />

hifiorias Cometarum, reperi quod quadruplo vel quintupls<br />

plures dctefii funt in Wemifphsrio Solem verfk, quam in Hernifphzrio<br />

oppofito, przter alios procul dubio non paucos quos<br />

lux Solaris obtexik. Nimirum in defcenfu ad regiones nofiras<br />

neque caudas emittunt, neque adeo illufirantur a Sole, ut n&is<br />

oculis [e prius detegendos exhibeant, quam dint ipfo Jove pros,<br />

Spatii autem tantillo incervallo circa Salem defcripti<br />

~~~ekmge major fita efi a latere ‘I’errz quad Solem rerpicit 5<br />

lnque parte illa majore Cometa, Soli ut plurimum viciniores9<br />

rnagis illuminari Iblent.<br />

cb~0,4 3. Hint ctiam manifefium efi, qUod Co& refifientia defiituuntur.<br />

Nam Cometaz vias obliquas & nonnunquam cur&i<br />

Ianetarum contrarias kcuti, moventur omnifariam liberrime, Se<br />

motus fuos etiam contra curfiim Flanetarum, diutiflime confirvanr.<br />

Fallor ni genus Planetarum fint, & motu perpetuo in orbem<br />

redcan t. Nam quad Scriptores aliqui Meteora effe volunta<br />

argumenturn a capitum perpetuis mutationibus ducentes, fundarnento<br />

carere videtur. Capita Cometarum Atmofphzeris ingenri<br />

bus cingun tur ; & Atmofphzrz inferno denfiores effe debent.<br />

Unde nubes funt, non ipG Cometarum corpora, in quibus mutaniofles<br />

Jllz vifuntur. Sic Terra ii e Flanetis ~pe&arecur, lute nubium<br />

fiarum proculdubio fpknderet, & corpus firmum filb IILIbibus<br />

prope delitefceret. Sic cingula Jovis in nubibus Planetr:<br />

illius formata efi, quz Gtum mutant inter 6% & firmum Jovis<br />

‘corpus per nubes illas difhcilius cernitur. Et multo magis cc+<br />

pora Cometarum Tub Atmofphzris & profundioribus 8r crafliori-<br />

$a.~ abfcondi debem


f’hQ~.‘I. If-Einc fi CometX in orbem redeunt: Orbes erul:c ~lii~,~<br />

fisz k tempera periodica erunt ad temgora periodica ~~~~~~~~~~~~~~~~<br />

iI1 aXium principalium ratione [efquiplicata. fdeuqw ~;l;‘orttcc.a<br />

maxima ex p,arte fupra Plaxietas verfantes, & e. nomine orbls<br />

axibus majoribus defcribentes, tardius revolventur. UC ii aXis cjr.,<br />

bh Cometa: fit quadruple major axe Qrbis Saturni, tcmpus revalutionis<br />

Comets erit ad tempus revolutionis Saturni, id cft, ad<br />

annos 30, ut 4 V’ 4 (ku 8) ad 13 ideoque erit annorum 240,<br />

CWU!~ 2. Orbes autem erunt Parabolis adeo finitimi, ut CurLlm<br />

vice ParabolE9 abfque erroribus fenfibilibus, adhiberi poflint.<br />

~cl&. 3. Et propterea, per Coral. 7. Prop. XVI, Lib. J, ~7fJocitas<br />

,Cometz omnk erit femper ad vclocitatem Planctaz cujrlfvis<br />

circa Sokm in circulo revolventis, in filbduplicata ratioac dupf;l:<br />

difiantix Planets a cenrro Sol& ad difiantiarn Comets a cenr’ro<br />

Solis quamproxime. Ponamus radium Orbis magi, feu EHipfeos~ .<br />

in qua Terra revolvitur femidiametrum maximam, tire partium<br />

'PQOOOOOOO: & Terra motu fuo diurno mediocri dekribec parses<br />

1720212, & motu horario partes 7~67~f. ldeoque C*omeca in<br />

eadeig Telluris a Sole difiantla medrocrl, ea cut?1 velocltXe quz<br />

fit ad velocitaren~ Telluris ut 4/z ad I~ defcribet mote ii10 ?iyna<br />

part=-s 2932741, & motu horario partes IOF 3.G&. Bn magor+s<br />

autem vel kkoribus diftamtus , motus turn dwnus rum horarw<br />

erit ad hunt motum diurnum & horarium in fubduplicata rations<br />

difiantiarum reciproce, ideoque datir-<br />

~~~~2, &, unde fi J&us re&um PyTab?k quadruple ma@ iitradio<br />

Orbis inagni, & quadrarum radll ~~IUS PWatur efk p!rtluln<br />

900000000 : area quam,,Cometa radio ad Salem ducilto fingulls d.iebus<br />

defcribit, erit partium 12 X6373$, & iingulis ho+ are;r iUa<br />

erit gartium 50682$. Sin lams r&urn majus fit vel m!llUS III C+<br />

$iOne quavis, erit area diurna & horaria major vd moor in ea:<br />

dem r&me fiabdupli~ata~<br />

,I354 MA.


i‘)E<br />

MWNDI<br />

'r y 5 'r E bl A 'I' h<br />

L E M M A v-d<br />

venirc iineafn curzlnm gencris ambalici, quL9 pev &a<br />

potcungue punEu traujbit.<br />

Sunto pun&a illa A, B,C, 93, E, F, &c. & ab iifdem ad x&am<br />

quamvis pofitione datam MN demitte perpendicula qmotcunquc<br />

AH, BI, CK, 2x, EM3 F.N.<br />

C6zJ 1. Si pun&orum .E& 1, I


tempt qaudcuir imwme<br />

I)efignent N-& IK, XL, LM tempora inter ~b~~rv~ti~~~~~~<br />

c&z F’g. paced.) ITA, I& KC, LV, ME obfervatas quinquc<br />

Iongitudines Cornerg, HS tempus datum inter obkrvatianem pri:<br />

mam & longitudinem quaGram, Et fi per punt% A,B,C,2,,h<br />

duck intelligatur curva regularis ABC9 E; & per Lemma :~perrius<br />

inveniatur ejus ordinatim applicata X S, erlt R S ~~~lg~~~~~~<br />

Cpdit”.<br />

lEadem method0 ex obfervatis quinque latitudinibus iwcnitur<br />

Iatitudo ad tempus darum.<br />

$$ ]ongitudinum obfervatarum parve ht. diEerenti;u, INCA graduum<br />

tanrum 4 vei 5; fuffecerinc obfervatlones tres vel ~U~CUO~<br />

inve&ndam longitudinem & laticudin<br />

n.ovam. Sin ~~~~~re~<br />

f &f&gemjg, pug3 graduufil XrS Vel bu~l~ obferva~iones<br />

e ,~d~~~~~.<br />

. ,I<br />

1<br />

“. ,. ’<br />

h.


B, P C, reEfis duabus pojtione datis A B,<br />

tam hbeant rationem ad inzlicem.<br />

A pun& ill0 P ad re&arum alterutram<br />

Al3 ducatur re&a qua3.G<br />

~$9 ) & producatur eadem verb<br />

re&am alteram AG ufque ad E, uk<br />

t F’ E ad ‘P D in data illa ratione.<br />

h AD parallela fit E G<br />

Bs srit a3 Q: ad<br />

‘go g+.E


Jungatur enh E 0 G.xalW arcum Parabolicurn AE! C if1 r, & a&a- LIBER<br />

tw P A!’ qua tangat eundem arcum invertice ,U & a&x,f?~ occur- Te~riuc.<br />

rat in X; 8~ crit area curvilinea AEXh A ad aream curvilineam<br />

ACTpA’ ut: AE ad AC. Ildeoquc cum triangulum A$E fit<br />

nd triangdum A SC in eadem ratione, erit area tora A,JE .X,MA!<br />

ad aream totam A?SCT~LA ut BE ad AC, Cum autem ~0<br />

iit ad SO ut 3 ad I, & E 0 ad X0 in eadem rathe, erit $3’<br />

$i EB paralitela: & propkerea ii jungatur BX, &it triangulum<br />

SEB rrianguIo XE B zquak. Unde fi ad arearn ASE X,UA .t<br />

addarur triangulum E XB, & de hnma auferatur triatrngulum<br />

LSEB, manebic area ASBXpA a;eaz ASEXpA azqualis,<br />

atquc adeo ad aream ASCTpFL ut AE ad AC. Sed area<br />

AJ B X,U A xqualis e& area ASB Tp A quamproxime, & hat<br />

area A S B Z”,U A efc ad aream ASCT,UA, u t tempus defcripri<br />

accu~ AB ad ~empus defcripti arcus torius AC. ldeoque AE<br />

efi ad AC in ratione temporum guamproxime. ,$&Es D.<br />

CoroZ. Wbi punEtum B incidit in Parabolx vertices ,Q efi A!E<br />

ad AC in ratiouc tcmporum accurate.<br />

Si jungatur p i$- kcans AC in 8, & in ea capiatur %fz qu22 $t<br />

ad ~23 ut 27 &!I ad 16 Mp: a&a Be fecablt chordam AC 1x1<br />

ratione temporum magis accurate quam priuy. J aceat autem<br />

put&.zm 9z ultra pun&urn 4, fi pun&urn q magls difiat a vertice<br />

principali Parabola quam pun&urn pj & cltra, ii minus dilZat ab<br />

eodem verticc.<br />

Nam 4SP ec Xatus re&um Parabolze pertinens ad verticem<br />

pa<br />

$d m m LEM.MA


Nam ?i Cometa velocirate quam habet in p, eodern +ter)7pore<br />

progrcderetur uniformiter in re& quz. Parabolam tangtt 111 ,ULL;<br />

area quam radio ad pun&urn S duLlto dekriberec, zcqualis effec<br />

are3: Parabolicz A SC,U. ldeoque contencum fub Iongitudine in<br />

tangente defcripta 6r longirudine S,uc, efkt ad conten.rurn fub<br />

longitudinibus AC & SM, LIE area A JIC,LJ ad trlangulum<br />

ASC M, id CR, ut S N ad S M. C&are AC e& ad longirudinem<br />

in tangente dekripram, ut S’p ad SN. Gum aurem velocitas<br />

Corner2 in altitudine SF’ fit (per Coral. G. Prop, XVI, Lib. 1,)<br />

ad velocicatem in altitudine J’,u, in filbduplicatn ratione SF ad<br />

S,U inverk, id eiE, in .ratione SF ad SN; longitude, hat velocitate<br />

eodem tempore defcripra, e’rit ad longitudinem in tangente<br />

defcriptam, ut S,U ad SA?, lgitur AC & longicudo hat nova ve-<br />

.locitare dekripea, cum dint ad .longitudinem in tangente ,d&crip-<br />

Pam in eadem ratione, xquantur inter k. g* E.D.<br />

Coral. Cometa igitu: ea cum vefocitate, quam habet in altitudine<br />

Sp -+- $?/A, eodem ternpore defcriberet chordam AC quamproxime,<br />

‘LEMMA


MATHE~~~ATIcA.<br />

L SE M M A<br />

XI.<br />

Nam Cometa quo ternpore defcribat arcum Parabolicurn AC’,<br />

eodem tempore ea cum velocitate qu.am habet in al,titudinc J*F<br />

per Lemma novifimum) defcribet chordam AC, adeuque (per<br />

L orol. 7. Prop. XYI. Lib. 1.) eodem tetnpore in Circulo cujus fernidiameter<br />

effet S-5”, vi graviratis fua: revolvendo, dcfcriberet arcurn<br />

sujus Iongitudo effet ad arcus Parabolici chordam AC, in fubdupIicata<br />

ratione unius ad duo. Et propterea eo cum pondere quocl<br />

habet in Solem in altitudine SF’, cadendo de altitudine illa in<br />

Solem, defcriberer femiire temporis illius (per Coral. 9. Prop, IV.<br />

Lib. I.) fpatium aquale quadrato fern& chorda iliius applicato<br />

ad quadruplum altitudinis ST, id eft, fpatium<br />

AQ<br />

-. Undc cum<br />

Q-P<br />

POndus Cornerg in Solem in alticudiae Sill, fit ad ipiius pondus<br />

in Solem in altitudine ST, Ut S’5? ad SILL: Cometa pondcre<br />

quad habet in altitudine SN eodem ternpore, in Solem caden-<br />

do, detiribet fpatium &‘q gPa 1 ‘d &, fpatium longitudini 1~ vel<br />

2Mp xquale. sE.2).<br />

PROPOSITIO XLi PROBLEMA XXI.<br />

Problema hocce longe difficillimum multimode.aggr$ust compofili<br />

Problemata quadam in Libra primo qux ad emus fo!Lkonem<br />

ij$kinJ. PoRea folutionem fequentem paulo fimpliciorem<br />

;XucOjp.a y 1.<br />

Q~lia:,nt~~r tres qbfervationes zzqualibus remporum-interva<br />

,,-nprqxime difiantes. Sit aurem temporls i~tervnlEum<br />

'ZZKZi &ometa gardius movetur paulo majus akero3 ita videlicet<br />

M m m z<br />

El&


45%<br />

PHILOSOPHIC<br />

NA<br />

~)e MUNDI ut temporum differentia fit ad Cimmam temporum, UC fumma temspSTEMRTGporum<br />

ad dies plusminus kxcentos; vel ut punRum 22, iyidat in<br />

pun&urn M quamproxime, & inde aberret vcrhs I pot~us quam<br />

verfus A. Si tales obkrvationes non pr;eiIo fint, inveniendus efi<br />

novus Cometz locus per Lemma gextum.<br />

Defignent S Solem, T, t, T tria loca Terrlle in Orbe magno9<br />

1TA, t B, -rC obkrvatas tres longitudines Comets, V tempus in==<br />

ter obfervationem primam & fecundam, W rempus, hirer fecundam<br />

ac tertiam, X longitudinem quam Cometa t6to 1110 temporea<br />

ea cum velocitate quam habet in mediocri Telluris k Sole difianria,<br />

dekribere poffet, quaque per Coral. 3. Prop, XL, Lib. II!.<br />

invenienda efiJ elk t Y perpendiculum in chordam a 7. 1x1 longn-<br />

‘.’D<br />

tudine media tI3 fitmatur utcunque pwn&um 23 pro roco Cometa:<br />

in piano Eclipticz9 & inde verfus Solem S ducatwr linea<br />

$ E, quaz fit ad fagittam tv, ut contentum fib SB 8t Sf qzwd,<br />

ad cubum hypotenufz trianguli re&anguli, cujus Iatera tint $23 &<br />

tangens latitudinis Cometa in obkrvatione fecunda ad radium tB.<br />

Et


PR~~~CIPIA MATHEMA=IXX 41;<br />

Et‘ per punQum E agatur ( per hujus rem. VII, > retin. AEC’, I,~~~~<br />

cujus parces AE, EC ad reQas TA cq TC rel.mill:ttx, i;llc nd T!.;~TJG~~<br />

invicem ut tempera V 8-z W : & erunt A & C’ loca Co[nct;y iI1<br />

plan0 Ecliptica: in 0bi’crvatione prima ac tertia qua[~proxil~~,e, ii<br />

mo*do B fir LOCUS ejus re& affumptus in obr’r\Tacione i&u&.<br />

Ad AC bikEtam in 1 erige perpendicuhm 1;. Per ~)~m@~~u B<br />

age occultam Bi iph AC parallelam. jqe occultam si recantern<br />

AC in A, & comple parallelogrammw~~ iJh. + (2113~ fc zqualem<br />

3Ih, 8c per Solem S age occultam G$ zqualem 3JG+3ihr<br />

Et: deletis jam literis A, E, C, Ia a pnniIo B VCJ~~S ~LHI~“IXHII ,$<br />

due occultam novam BE, que fie ad priorem 6 E jn dup]icat:l<br />

rarione difiantia: 6 S ad quantitatem 8~ -t-4 i A. Et per p~l&um<br />

E iterum due re&am ABC eadem lege ac prim, id c/i-, ir;a ul: ejus<br />

partes AE & EC tint ad invicem, UT rempora inter obfervationcs<br />

V & W, Et erunt A & C loca Comet32 ma@s accurate.<br />

Ad AC bife&am in 1 erigantur perpendicula AH, CN, JO,<br />

quarum Afti si C1\T fint rangentes latitudinum in obiervatiouc<br />

prima ac rertia ad radios 2-A & TC. Jungatur MA? kcans IQ<br />

in 0. Conftzituatur re&angulum i_Th~ ut prius. In IA produQa<br />

capiacur ID zqualis Sp-+-$a’h, & agaeur occulta 0 13, ’<br />

D&de in MN verbs A7 capiatur MT’, quz fit ad longitudinem<br />

i”upra inventam X, in fubduplicata ratione mediocris difhtia Teliuris<br />

a Sole (ku kmidiametri Orbis magni) ad diftantiam 0 2).<br />

Si pun&urn T incidat in pun&urn N; erunt A’, B, C tria loca Cometz,<br />

per quaz Orbis eius in plan0 Ecliptics defcribi debet. Sin<br />

pun&-urn T n0n incidat in punQum AI”; in re&a AC capiacur<br />

CG ipfi NT aqualis, ita ut punEEa G & ‘P ad cafdem partes<br />

reti;e iVC jaceant.<br />

gadem method0 qua pun&a E, A, C, Gj ex affimpto pu!~Bo<br />

B inventa runt, inveniantur ex affumptis utcyque pun&is aliis<br />

b or p pun&a nova e, a, c,g3 & B, a, xj Y. Demde fi per G g, r<br />

ducatur circumferentia circuli Gg 7, fecans re&am TC in Z: erlc<br />

z locus.Cometa: in plano Ecliptlcz Et-ii in. AC, n C, u x capiantur<br />

A& df, c.G~, ipfiS CG, cg, XY refp$ve ~q~uales, 8.~ per<br />

pun&a $‘,f’.q ducatur circumferentia clrcuh Ff Q, iecaw yeaam<br />

AT in X5, erit pun&urn X alius Cometrz !OCUs in plan0 Echpticx.<br />

Ad pun&a x & Z erigantur tangenres latltudmu? Comets ad radios<br />

TX & Iz; & habebuntur loca duo Cometa In C)r*be proprio..<br />

‘Denique (per P~op.x~x. Lib, 1.) umbilico SB per loca Ala duo de-,<br />

ffcribatur Parabola, & haze erit Trajy,aoria$omet% &ES x<br />

con--


Be MUNtll Confiru&ionis hujus demonfiratio EX kemmatibus conb;=quitur :<br />

SVsTEhrhTe quippe cum rei% /IC fecetnr in E in ratione temporw~h per<br />

Lemma VU> ut oportet per Lem. VIII : 8.1 B E per Lcm. XT.<br />

iir pars r&33 .I3 S vel B t in plan0 Ecliptic32 arcui ABC &<br />

chords A E C interje&a j EC MT (. per Coral. Lem. x. ‘) Ion@--<br />

tudo fit chorda arcus, quem Cometa in Orbe proprio inter obkrvationem<br />

primam ac tertiam dekribere debet , ideoque ipfi<br />

MN zqualis herits ii modo B fit verus ~osnet;x: locus in plarm<br />

Ecliptiszc.<br />

Gzterum pun&a 23, b, P non CJ.UXlibet9 fed vero proxima eligere<br />

convenit. Si angulus A&!!, in quo vefiigium Orbis in<br />

plano Ecliptica dekriptum f&at re&am t& przterpropter innotefcat<br />

5 in an&o illo ducenda erit re@a occulta AC, ~LISZ fit<br />

ad g Tr in iitbduplicata ratione SRad St. Et agendo re?am<br />

SEB cujus pars EB zquetur longitudini VZ, determinabltur<br />

pun&urn B quod prima vice ufurpare licet., Turn re&a AC de-<br />

Eeta &z kcundum przcedentem csnfiruflionem iterum duea, 6-z~<br />

inventa


”<br />

PRINNCIPIA<br />

?ktYlTfEbn/lATnciti.<br />

4jT<br />

inprenta infiiper longitudine M-T ; in tB capiatur pun&urn 6,<br />

LfSftZ<br />

ea lege, ut fi TA, TC) k mutuo kcuerint in z fir difiantia r.h Tcc’~~u;~<br />

ad difiantiam TB, in ratione compofita ex ratione MT ad M.N’<br />

& rarione fubduplicara SB ad J IT. Et eadem methodo invcniendum<br />

erit gunEtutn tertium ,G, G mode operationem tercio repe-<br />

..tere lubet. Sed hat methodo operationes du;c ut plurimum iiaf-<br />

$kqxine. warn fi d.ifiancia I36 perexigua obvenerit; poffquam<br />

inventa fimt pun&a F,f & G, g, a&z re&h Ff S: Gg fecabuns<br />

T A Sr T C in pun&is qwfitis X & Z.<br />

Proponatur Cometa anni 1680. Mujus motum a FZazy?e&a<br />

obkrvkum Tabula fequens exhibet. ”<br />

1680 Dec. 12<br />

21<br />

24<br />

26<br />

29<br />

30<br />

1681 yand 5<br />

9<br />

IO<br />

.I3<br />

25<br />

30<br />

Feb. 2<br />

rt33.appar<br />

i’* 46’<br />

6.32$<br />

6.12<br />

5 ’ ‘4<br />

7*55<br />

8. 2<br />

5* 51<br />

6.49<br />

5 - 54<br />

6.56<br />

7 d-4<br />

8. 7<br />

“6iZO ,<br />

6.50<br />

Temp.vcrun<br />

a: q.b’* ;:<br />

6*36*59<br />

6.17~52<br />

5.20.44<br />

8. 3* 2<br />

8.10.26<br />

6. I.38<br />

7* OS53<br />

6. 6.io<br />

7- 8q.55<br />

7 •<br />

$8.. 42<br />

‘8.21 .53<br />

n Long. Solis<br />

-..__I_<br />

I vy &;.2j<br />

I’I. 6.44<br />

14. 9.26<br />

rb. 9.22<br />

19.19 •<br />

20.21. g<br />

26.22.18<br />

43<br />

LC 0.29. 2<br />

L-27143<br />

4.33 .fO<br />

-16.45.36<br />

21..453 e 58<br />

f*3405I 1 24-46.59<br />

Lonq. Colllet~~<br />

gr. *<br />

d 6.313;<br />

z 5. 7*38<br />

18.4g.10<br />

28.24. G<br />

Kr3.11.45<br />

‘7-39* 5<br />

r 8.49.10<br />

18.43.13<br />

20.40.57<br />

5”:;;:;5<br />

I3 eI9.36<br />

1 ~5 • 1 3 ’ $8.<br />

Lat. Comets<br />

g2rj*. A.<br />

21.45.30<br />

“5.23.24<br />

27 ’ 0. s7<br />

28.10. 5<br />

3X.11.12<br />

26.r5.26<br />

24.12.42<br />

23 .44.. 0<br />

22.17.36<br />

qe56.54<br />

16.40.57<br />

rd. 2. .2<br />

~15.27.23<br />

. .<br />

His adde Obkrvationes<br />

quafdam ‘e nohis.<br />

corn., Lat.<br />

12 gr*, • &,6’;j<br />

I2<br />

: ;$<br />

I.2<br />

I2 .20<br />

I2 . 3:<br />

II 945; I<br />

& Micrpmetro filifquibus<br />

infirumentis<br />

&


4E 6 E’E-IILosSOlP~IE NA~WRALIS<br />

i:,;PFi;,;h;,; 8.z poficiones ,fixarum inter fi & pohiones Cometaz ad fiXaS dcterminavimuo.<br />

Defignet A itellam in hifir calcaneo Perki<br />

( Bdyera 0 ) B fiellam fequencem in finifiro pede (Bayer0 ab hat reQa effet 2 CD. L M<br />

erat ad LB ut 2 ad p & prod&a rranfibat per fiellam EL<br />

dererminabanrur pofitiones fixarum inter k<br />

Die Vcneris I;eb. 27. St. vet. Her. 8f P. M. Comet3 in p cxiitencis<br />

diitantia a aella E erac minor quam 15 A E, major quam<br />

+ AE, adeoque zqualis ;4. AE proxime; & angulus Ap E nonnihil<br />

obtuiis erat> f2d fere reCtus. Nempe fi demitteretur ad<br />

PE perpendiculum tib A, difiantk Cometa: a perpendiculo iI10<br />

erat $p E.<br />

Eadem notie, hors p;, Comets in ‘2’ exifientis diilantia a Aella<br />

E era6 major quam ++ AE, minor quam ji AE) adeoque aqua-<br />

2<br />

! lis


\ P~~Nc~~ht.<br />

M~‘l33EAL4T~~,4.<br />

41 7<br />

lis<br />

rAE, f&l ;$ AE quamproxime. A pcrpcndicu\o autcnl a i.‘:,“i.‘,bs.<br />

fid~‘A adI se&an ‘BE demiffo, difiantin Comet- crrlt : ‘p lj;,<br />

De @is, FL& 27. IIOL 8: p, kf. c omers in fl cxiltew‘is cfifhltia<br />

a fklla 0 aquabat difianriam fteliarum 6x& ~1, k r.e:,y~,,<br />

2Jo produEta war&bat inter fiellas IC & B. Pofiti*ncm ilL~l~~s<br />

re&x ob nubes incervekentes, magis accurate d&nire 11ofl pot;j,<br />

t Die 6 tis, ikf& 13 hot-. 11. I?. M. Cometa in R exiltens, ficllis<br />

I’C & c accurate interjacebat, 2% re&22 CR fr’ pars &‘R pauP<br />

major erat quam $CK, 22 paulo minor quam f CfY+$CR,<br />

3deoque zqualis xx+*~, CR feu a+cI<br />

erat quinruplo major quam diitancia fiella: 5’. Itern reQa NS<br />

produ,Aa tranfibac inter fleIIas H &z I, quintuple vel fextuplo propior<br />

exifkiis fiellaz H quam trella .I.<br />

Die h xxi,, Mirt. 5. hor. T I;. P. M. Cometa exifiente in T:,<br />

re&ta ik?aP azqualis erat 4 ML, & reQa L T produQa tranfibat<br />

inter 6 & F, quadruplo vel quintuplo propior F quam B, auferens<br />

a 6 F quintam vel fixtam ejus partem verfiw F. Et MT:<br />

produ&a tranfibat extra fpatium BF ad partes fielk B, quadruplo<br />

propior exifiens fiellz B quam itelk .F. Erat M fiella pe!exigua<br />

qu3= per Telefcopium videri vix pocuit, & L fiella major<br />

quail nfagnitudinis oQavF.<br />

Ex hujdiiodi obfervatlonibus per confiru&iones figurarum k<br />

computationes (pofito quod ftellarum A & B difianria elkt<br />

7 gr* 6’, 46”) & flellx A 1oI~gi~udo 8 2Gg’* 41’. 50" & latitd


nibus hn&enus defcriptis cres, quas FZ~~,/feu'itts habuit ‘Dec. 21,<br />

$liL. j-3 (1:c,pn. 25. Ex his inreni St partium 9842,I ik Yt parrillm<br />

+55, cluales I oooo func femidiametcr Orbis magnil TUP<br />

ad opcracionem primam aiTumend0 tB partium 5657, inveni<br />

SB pi+;, BE prirun vice 412, SJJ 9503, in 413: BE fecunda<br />

vice +2x, Cl%> 10186, X 8528,4, 11dP 8450, i%ilN 847~~<br />

NP 2.f. Tfndc ad operationem kcundsm collegi difiantiam<br />

sb f6.f.O. Et per hanc’ operationem invcni candem diitantias<br />

TS 4773 &I TZ 11322. Ex quibus Orbem definiendo, inveni<br />

Nudes ejus dekendentem in E & af?endencem in w I 6’753’;<br />

JInclinationem plani eius ad planurn Ecliptics 61 gr* 2o’j 5 verticem<br />

eius (feu Periheiium Cometaj diftare a Nodo 8s’. 38’, &<br />

ci-k iI1 f 27 F’ 4;’ cum latitudine aufirnli 79’. 34’; k ejus latus<br />

I-efium ctTe 23~,& arenmque radio ad Solem duQo Gngulis diebus<br />

detiriprnm 33 585, quadrato femidiametri Orbis magni pofito<br />

zooocoooo j Cometam vero in hoc Qrbe fecundum feriern cgnorum<br />

procefliffe, & Drcemb. 8”. 0”. 4’. P. M. in vertice Orbrs feu<br />

Perihelio fuiffe. Hzx omnia per fcalam partium aqualium &I<br />

chordas angulorum ex Tab& Gnuum natul’alium colle&as, determinavi<br />

Graphice j confiruendo Schema fatis amplum, in quo videlicet<br />

kmidiamerer Orbis magni ( partium roooo) zqualis effet<br />

digitis 16f pedis Anglicani.<br />

Tandem UC conftaret an Cometa in Orbe Gc invent0 vere mo.=<br />

vcretur, collegi per operationes partim Arithmeticas partim Gra-<br />

~hicas, iocn Cometa in hoc Orbe ad obkrvationum quarundanx<br />

kmpo;a: uti in Tabula fequente videre licet.<br />

Difimt.Co- LongColleA, Lat. Coll&. Long. Obl.<br />

metx a Sole<br />

- --- .~~~ -- --<br />

LV.<br />

DEC. 12 2792 VP 6.33’ ST& I9 5 3I’f<br />

29 8.403 x 13 . 13; 28. 0 x13 III;<br />

liitv, j 1G669 8 17 . o I $ .2gf 8 16 $59;<br />

A&w. j 21737 29.19; 12. 4 23 • 209<br />

Lat. Obf. ?i&r. Differ.<br />

-_I--<br />

rL,ong. Lat.<br />

-<br />

28 +i.-+<br />

Io,Lz + 2 -1o;l;<br />

27: + 0 +- 22<br />

3$-r+ t<br />

Poka vero ~LI&~‘~~s nofcer Orbitam, per calculum Arithmeticum,<br />

accuratius deterfninavir quam per defcriptiones linearum<br />

&xi ficuit j & rerinuit quidem locum Nodorum in GTE & VP 1 IF f3’,<br />

& llnclinationem planiOrbitaz ad Eclipticam br 6’. 20/f, ut & tern--<br />

pus PeriheIii Comets Ik)ecemb. ad. oh, 4’ : difiantiam vero PeriheIii


~~~bKXh4<br />

MATMEMAT~c,A.<br />

4j3<br />

heK a NO& afcendcnte, in Orbita Oomerx mcnruratan~, invcnir<br />

1.:‘3T.1:<br />

Cffe 9@ 2o’a & LlltUS retitum J?arg,bo]g efl: 243 prrrtium, cs- ?‘i:r:rt!.r.<br />

Jfiente mediocri SOILS a Terra difiantia partium loooO. Et cs his<br />

datisJ caIcuIo itidcm Arithmecico accurate infiituco, ]oca ~~~~~~~~<br />

ad obfervationum cempora compuravir, nt fcequitur.<br />

Tempus verlll~, Dih~tia Long. camp. Lat. con1p. Er1o:e: in<br />

Cormtx a sg<br />

Long. Lit.<br />

d. i,. --<br />

Dec. 12, 4.48. b: 28028 w E,,.,, s”:.r;, a;‘Bor, -I’.+&.<br />

21 *<br />

6.36 *YP 6107~ % 5 . 6 .30 21 ,43. 20 -1. 81--2.*:<br />

240 6.17.92 70008 18.48.20 25.22.40 -0.50 - 0 .4+<br />

26. y.20.44 7s’s76 2S.22.4~ 27. 1.36<br />

29. 8. 3. 2 84021 Xl3 * 12.40 28. ILJ. ,o<br />

. 8.10.26 8666 I 17.40. f 2s.rr.m<br />

j%n. ‘i. ; . -i . 3s 101440 T 8.49.49 26.15.rf<br />

.<br />

IS .44.36 24.12.f4<br />

IO.<br />

•<br />

6.<br />

o-s3<br />

6.10<br />

IIO9.r 9<br />

113162 20 *41. 0 23.44* IO<br />

S-H 120000 26. 0.21 22.17.30 0.47 -0. G<br />

::: ::s* .+2 145370 8 g-33*40 ‘7*.c7*5)*<br />

30. S.21.53<br />

‘J-j-303 ‘3. 17.41 16.42. 7<br />

Feb. 2. 6.34*~1 IGog~’ 1g.r1.11 16. 4.ff -2.37 2 * 13<br />

5-O 7. 4-41 1666&6 ld.p8*2J 1f.2g.13 ,r.zr $ 1 .$O<br />

2j?. 8.19. 0 2OZf70 26.Ir.46 12.48. o -2.31 -+I. s<br />

Mav. j-.rr -21 . 0 2 r62oy 2g.18-35 IZ. f-40 -1.16 +z.,~<br />

*’<br />

Apparuic etiam hi6 Cometa menfe Novenabrt pracedente, &<br />

die undecimo hujus menfis fiylo vereri, ad horam quincam maIturinam,<br />

Cantwar in ArtgZk vifiis fuit in T 12: cum laticudine<br />

boreali 2 w circiwzr. CraflifIima fuit hzc Ubfervatio : meliores iirnr:<br />

qua2 fequuntur.<br />

NOV. 17, fi* vet. ~oz~tb~tis & ibcii hora fexta maturirla Rorrr~<br />

( id & , hors 5, IQ’ &w&zi ) filis‘. ad fixas apphcatis pometam<br />

obfervarunt in 3 8, so’, cum latitudine aufirali ogr- 40. Extant<br />

eorub Obfervationes in tra&atu qucm Tonth&tis, de hoc Cometa,<br />

in lucem edi&, C&Z.U qui aderat SC obfervatione? fklS in Lpicola<br />

ad 2). Caflngm mifit, Cometam eadem hora vrdit in ;r: 8 V*<br />

a~’ cum latitudink a&raIi ogre 30: Eadem hora GalZ&ilcs etiam<br />

Gometam vidit in e 8 gfi fine Iacitudine.<br />

NOV. 1~; hors matutina 6. 30’ Rmd (id & hors fs 4:’ &NdiPi)<br />

fpO@$,$~as .Cometam vi&t in c 1,~ g’* 30’ cum latltudme au:<br />

firal; I 6 2~3’. C&w in @ 13 gr* d? 9 cum laritudine aufiralz<br />

I IF- Qor. G&“&jas autem hOra matutlna ‘ie 30’ Rotif?, EFmjca$<br />

Vi& ia, gi 138” m~~4,<br />

cnm latitudine: aukall I grS 00. s .<br />

1<br />

Ango ‘in, A,---d&a F/&xiela/% apud Gdll~s,. Ilpra qujt1r.a matuM2<br />

(id CR,, llorlr 5, + dondjnj) Cometam vidlc in medlo lnCcf fiiI$<br />

Nnn 2


D 1' :-I~N ~1 cluas p;lrvas, q~~:~r~lfl~ utla media efi trium in re&a linca in Virgis<br />

Y 5 ?’ 1: ?J i\ ‘1‘ E<br />

nis nultrali manu, c3= altcra eft extrcma alx. Uncle Cometa tune<br />

fiiit in ~2 I 2. +d, CLIIII latitudine autlrali 50’. Eodfni die Bo-<br />

Jfu?z~‘s in &,‘oviz-~hzgZin in Latitudine 4rt graduum, hors quinra<br />

IlmutiI-~~, (id elt Lon&zi h ora mattatina 9. 44’ ) Comcta vilils<br />

co propc 2 14, cum Iatitudine au&raii L gr. 301, uti a CZ. H&L--<br />

li~ii, accepi.<br />

2bT.m. 17. hora mat. 4: rCl’nrz$ndaigr‘&3 Cometa ( obkrvante juvcwe<br />

yuodatn) difiabat a Spica YT quail 2 F’ Boreazephyrum<br />

verbs. E.odrm die liar. 5. m3t. Bo$3orZzt~c in iUoV6z~Angdia, Comorn<br />

difizbnt a Spica ‘3 ;5radu uno, di%crentia latitudinum exiilencc<br />

+I’. E o d em die in lnfula ydmnicn, Cometa diftabat a Spica<br />

incervnllo qwfi gradus units. tic ex his obkrvationlbus inter fk<br />

co!latis colligo, q~od horn p.+.+‘. Lozdizi, Cometa erat in ti 18 G+<br />

bo’, cum latitudine aufirali I gr* 18’ circiter. Eodem die D. Ar-<br />

T~;LFIL.F &tori'r ad fluvium Tdtuxent, prope *w@i?zg-Creek in ik%p-31-<br />

Land, in confinio PYrgin& in at. 38fg” hora quinta matlatin<br />

(id efi, hors 10% Lo,w!irzi) Cometam vidit fupra Spicam ‘g , &<br />

cum Spica propemodum conjun&um, exifkente diitantia inter eofdem<br />

quafi 2 6’~~ Obfervator idem , eadem hors diei GzqLlentis )<br />

Cometam vidit quail 2gL inferiorem Spica. Congruent hz obfervationes<br />

cum obfervationibus in Naun-Anglia & ydnaaica faQis><br />

G modo difiantiz (pro motu diurno Comets) nonnihil augeantur,<br />

ita ut Cometa die priore Superior efit Spica T, altitudine<br />

I gr. circiter, ac die pofieriore inferior eadem itella, altitudine perpendiculari<br />

3 gr* 40’.<br />

Nov. 20. D. Mon~ennw Afironomia Profeffor TDadtienjs, hors<br />

fexta matutina Yenniis (id efi, hora 5, IO’ Londinj) Cometam<br />

vidit in =1: 23 gr*, cum latitudine aufirali I gr- so'. Eodem die<br />

BoJonide, difiabat Comcta a Spica F?~ 4gr* longitudinis in or&-<br />

rem, adeoque erat in 2 23 gr. 24’ circiter.<br />

NW, 21. To~t/5ms S= focii her. mat. 7; Cometam obfirvarunt<br />

in ti 27 gr* fo', cum latitudine aufirali x gr* 16'; Ango Ilora<br />

quinta matutina in e 27gF* 4f, Molatenarr4.s in G 27 gr* 51’. Eodem<br />

die in lnfula Jamaicu, Cometa vifils efi prope principium<br />

Scorpii, eandemque circiter laritudinem habuic cum Spica Virginis,<br />

id efi, 2 gr* 2'.<br />

iYbv. 22. Comet2 viliis efi a Montenaro in IR 2. 33’. Bo$.I~~~<br />

autem in &wz-&gi.k apparuit in w 3 ~0 circiter, eadem fere<br />

cum llarisudiae ac prius, id efi, I gr* so'. Eodem die Landini,.<br />

1.<br />

IlOCl


hOl% 1313t. G? %~~~kifkf noflcr Comctam vidit in ril 3:~. .,Oi c.r- I,!::!.<br />

cites, idqLlC in liuea re&a quaZ traniit per Spicam Vircrinis k ‘1’L.i; 4 J ‘I-’<br />

Car Leonis, mm cxde quidem, ied a linea il/a pau]ulu~, dcfie-<br />

&entem ad boream. M~~tennr~~s itidem notavic quotd l;ilca :I<br />

Gmeta per Spicam duba, hoc die & fequentibus tran{ib;$t per<br />

au8rale Hiatus Cordis Leonis, interpofico pel.parlTo iiltervalfo irIcer<br />

. Cor Leonis & hanc Jincam. Linea re@a per Car Leonis &<br />

SpiCXIll Virginis tranfiens, Eclipticam f&it in q 3 gr. +6’, ifI alngulo<br />

2 w= 71'. Et G Cometa locatus fuiflet in hat ]ilje;l in 1;~ 1 R’.<br />

ejus laritudo ftiiiret 2 gr* ~6'. Sed cum Cometa ~oII~;o~~~~u~&<br />

Ho&~o 8z Montenaro, nonnihi! diftaret ab hat linea borean] veriis,<br />

Iaritudo ejus fuit pau10 minor. Die 20, cx obfervatiolle JJ~~?J~<br />

$t~~uri~ laricudo ejus propernodum zquabat latitudincm Sp& rq,<br />

erarque 7. u* 30’ circiter, Sr confkatientibus Hook& Nm~c~~~~-o &<br />

Angone perperuo augebatur , ideoque jam fknfibiliter major erat<br />

quam 1 gr* 3o’. Inter limites autem jam COnCkitutos 26’. 26’ &<br />

I gr* 3& magnitudine mediocri Iatitudo erit 16~. 58’ cireicer.<br />

.Cauda Csometaz, confentientibus Houkio 8c M'untenaro, dirigebatur<br />

ad Spicam y, declinans aliquantulum a Stella ifia, juxta Hoo,&w<br />

in aufirum, Juxta Montcnartim in boream j ideoque dcclinatio illa<br />

vix fuit knfibilis, & CaudaBquatori fere parallela exiftens, aliquantulum<br />

defk&ebatur ab oppofitione Solis boream verbs.<br />

NOV. 24,. Ante orrum Solis Cometa virus efl a Mu~~~~zaro<br />

Jn 14’ I 2 IS 52’, ad boreale latus re&-e quz per Car Leonis & Spicam<br />

Virginis ducebatur, ideoque latitudinem habuit paulo minorem<br />

quam _II 2 g!. 3 8’. ]E-lsc latitudo uti diximus, ex obfkrvationibus<br />

~o~tkr~ar;, &zgonis &, Nook& perpetuo .augebatuFj ideoque jam<br />

paulo.‘major erat, quam 1 g? ‘58’; & magnrtudine mediocri, abrque<br />

notabili errore, ftatui pot& 2 g’s 18’. Latitudinem TOT?~BU &<br />

&$‘&& jam decreviffe volunt, & c@u< & Ot@rvator in NQw-<br />

/B,fia eandem :fere magnitudinem retmulffe, fccl@t gradus unius<br />

ate1 ~U~i~~ cum ;cimifle.. Crafflores:iunt,lob~rvauones TUZG&& &I<br />

c~J/;;; cE prsf&im qua per Azimuchds & Aititudines capieban-<br />

Cur, Ut pz ea: G&?&i: meliores iunt ex qua per poliriones COmet-a:<br />

.ad fixis a. Mmtenam IJookio, Angon? & Obferv~core in<br />

flbea”;;4ngliq &*nbl~nunquafn a+Ton$h?o & Cetlio CUIlt fJ&Zj.<br />

,,,, ~a~ dbl]atis: Obfervationibus Inter ce, colliger! vidcor quad.<br />

cbmdta ihod m&fc.‘cir$um ,fere maximum d$$+fpfit~ iecanInm<br />

,EcIiptikab in n~.‘25. ~2, idque in an@o 3 w 1% qL~“m~roxIme.<br />

~~~ & Hgptegdygs @bitam ab Eehpt~ca m.aufirw% cribus faltcm.


4cz PHIEOSOPHI~ NA<br />

17 E M I”::,,1 tern gradibus declinaire dicit. EC cognita curfus pofitione, Ion-<br />

S Y i T !:! 5 .i“i‘<br />

I. gicudincs Comctaz ex obfervationibus colleAaz, ad incudem jar11<br />

revocnri poff‘unt ei melius nonnunquam dctcrminari, ut fit in .kqucntibus,<br />

Cellius Novemb. 17, obfervavit difiantiam Cometa: 2<br />

Spica IT, zqualem efi difiantix ejus a itella lucida in clexrra ala<br />

c orvi : & hint locandus efi Cometa in interfe&ione hujus circuli<br />

qucm Cometa motu apparente defcripfic, cum circulo maxirno<br />

qui a fixis illls duabus aqualiter difiac, atque adeo in ti 7”” 54’3<br />

cum latitudinc aufirali 43’. Przterea Monteww, Novemb. 20.<br />

hora kxta matutina Venetiis, Cometam vidic non totis quatuor<br />

gradi bus difIan tiam a Spica ; dicitque hanc difiantiam, vix zquafi<br />

difiantiam fiellarum duarum lucidarum in alis Corvi, vel duarum<br />

in ju La Leonis, hoc efi 3 gr- ?I 30’ vel 3 2’. Sit igitur difiantia<br />

Cometre a Spica 3 gr* 30’, -& Comer, locabitur in ti 22 gr* 46’, cum<br />

latitudine aufirali I gr* 30’. Adhac Mon~twwi, Novemb. a E, 22,<br />

24, & 25 anre ortum Solis, Sextante aneo quintupedali ad minuta<br />

prima & femiminuta divifo SE vitris Telekopicis armato,<br />

diitantias menfuravit Comerz a Spica 89’ z8’, 13 gr- IO’, 23 gra<br />

30’, & 28~” 13’: & has diitantias, per refraaionem nondum corre&as,<br />

addend0 longitudini Spica, collegir Gometam his temporibus<br />

fuiffe in ti 27”‘. 51’, nl 2gr* 33’, SL lzgr* $2' & nt IT&~* 4~'~<br />

Si difiantis ifla: per refraeiones corrigantur, & ex difiantiis corre&is<br />

difFerentiz longitudinum inter Spicam & Cometam probe<br />

deriven tur , locabitur Cometa his remporibus in e 27 gr* 52’,<br />

v. 2 gr. 36’, 9 I2 gr- 58’ 6-z 9 17 gr* 53’ circiter. %atitudines autern<br />

ad has longitadines in ,via Cometa= captas, prodeunt I gr- 45’><br />

1 gr- 'itI', 2 gr- 23’ & 2v 3L Harum quatuor obfervationum ho-<br />

1’3s matutinas Morztenarw non pofuit, Priores dua: ante horam<br />

fextamJ pofieriores (ob viciniam Solis) poft Gxtam fa&Eas<br />

videntur. Die zzJ ubi Cometa ex obkrvatione Mtwztenavi locatur<br />

in 1112 6’. 36, Hook& nok eundem locavit in w 3 P 30’<br />

UC i‘ipra. Montcnmtis in defe&u, Hook& in exceffu erraffe videntur.<br />

Nan-r Cometa, ex ferie obfervationum, jam fuit in Q 2 gr- 56’<br />

vel trl 3 gr* circiter.<br />

Obfervationum fuarum ultimam inter vapores 86 diluculum<br />

captam, Montmams fufpe&am habebat. Et CeZkz’~s eodem tempore<br />

(id elt, Novella. 2 5) Cometam, per ejus Altitudinem 6-z Azi..<br />

nruthum locavic in III 15gr* 47’, cum latitudine au&ah quaft gradtrs<br />

unius Sed cellitis obfkrvavit etiam eodem tempore, quad<br />

Conaeta erat in llinea re&a cum iteIla Irucida in dexcro femore<br />

Vir-


~S‘a,INCJPIA R/~A’THEMA:S:~CA, &q<br />

Virgillis 8~ cum Lance auhali Libr;P, & hat hea recat: viam tlIlr.c<br />

Cometx in 14 18gr~ 3G’. TOEV~~EZSS etiam eodem ternpore obfir- TE KTIU:<br />

vavib quad Cometa erat in refia tranfeunte per Chelam auarimm<br />

Scorpii & per fMam quz Lancem borealem fequitur: &<br />

hzc re@.a &cat viam comettr: in ?lt 166’. g,‘. Qbfirvavit ctiam,<br />

quad Cometa erar in reQa tranfeunte per IteIiam fupra Lancem<br />

auftralem Libra & fiellam in principio pecks fecundi Scorpii: &<br />

hw re&a kcat viam Cometa in 71117gr* 5+, Et inter longitudines<br />

ex his r&us Obkrvationibus fit derivaras, longitude mediocris<br />

elt ITI 17 IF* 42’, qu3e cum obfervacione MoatenaPi Catis.<br />

congruit.<br />

Erravit igitur ChlZ&s jam locando Cometam in 11 15 gr- 475<br />

per ejus Azimuthum & Altituciinem. Et fimilibus Azimuthorum.<br />

& AItitudinum obfervacionibus, Cellizs & Tontthm non minus<br />

erraverunt locando Cometam in tit 20 &, nt 24 diebus duobus.<br />

.Cequentibus, ubi fiella fixa: ob diluculum vix aut ne vix quidem. -<br />

apparuere. Et corrigenda Cunt 11~ obkrvationes per .additionem.<br />

” duorum :graduum, vcl duorum cum femifk.<br />

Ex omnibus ,autemOhfervationibus inter fe collatis & ad meridianum<br />

Lo&&i redu&is, colligo Cometam hujui’modi curfum.<br />

quamproxime defcripfifi.<br />

Temp. nied. fi. vet.<br />

A&g. 36d.. 1;. . xd<br />

17.17 . IO<br />

18.21 . 44<br />

19.17 . 10<br />

20.17 fere<br />

, 2 I . I 7 fere<br />

23 ,,17i fcre<br />

24 . r7$ f&-e<br />

26.18 . 00<br />

I Long. Cometa:<br />

I% I” . d<br />

‘1 2 • 52<br />

x8 * 40<br />

22 . 48<br />

27 * 52<br />

111 2 t $6<br />

12 , 58<br />

I7 • 53<br />

26vel 27gr*<br />

1 Lat. Come&<br />

ir.<br />

o .44Aufi.<br />

I. 0<br />

1 .I8<br />

1930<br />

I.45<br />

I .58<br />

2.20<br />

2 029<br />

2,4z<br />

Loca autem Cometazin Orbe Parabolic0 computata, ita fe, babent;<br />

verum DikCom. % @<br />

Long.<br />

camp+<br />

- 1<br />

Lat., camp.<br />

20.~6.y3 73012<br />

2s. 17. 5 64206<br />

1 01 54799<br />

18.4.1.50 1.17.30<br />

27’59*40 I *44-25<br />

Irlrj.rg.r5 2.21 ,.* 8


w4 PHILOS~I)HL!E NATURALIS<br />

DC RIUi:l31<br />

-‘,.I : Cotlgruunt igitur Obkrvationes Afironomica, tam menfe &-<br />

” ” LX1”‘rE wrnb~i quam menfibus quaruor fkquentibus2 cum mo,tu Comets<br />

circum Solem’ in Trajc&oria hacce Parabolica, atque adco unum<br />

& eundem Cometam fuiffe, qui menfk&uembri ad Solem defiew<br />

dit, & menfibus fequentibus ab eodcm afcendit, abunde confirmant,<br />

ut & hunt Cometam in Trajeeoria hacce ParaboIica dela-<br />

4um fuiffe quamproxime. MenG bus ZIecembri ) $%w~ario 3 Febmario<br />

& Martio, ubi Obfirvationes hujus Cometae funt fatis accuraw,<br />

congruunt eadem cum motu ejus in hat TrajeQoria, non<br />

minus accurate quam obfervationes Planetarum congruere folent<br />

cum eorum Theoriis. Menfe No&n6r~, ubi oblrervationes lint<br />

craffz, errores non funt majores quam qui cl;afitudini obfervationum<br />

tribuantur. Traje&o.ria Comets bis fkcuit planum Ecliptics,<br />

& propter,ea non fuit re&ilinea. Edipticam kcuit non in<br />

oppofitis cc& partibus, fed in fine Virginis & principio, Capricorni,<br />

intervallo graduum p8 circiter; ideoque curfus Cometas<br />

plurimum defle&ebatur a Circulo maximo. + Narn 4k menk Nowem6ri<br />

curfils ejus tribes Caltern ‘gradibus.ab Ecliptica in a&rum<br />

.declinabat, & poRka menlre “Decembri gradibus zp vergebat ab<br />

&liptica in. feptentrionem) partibus duabus Orb& in quibtis<br />

Cometa tendebat in Solem & redibat a Sole, angulo apparente<br />

graduum plus triginta ;2! invicem declinantibus, ut , obfervavit<br />

Montemzrus. Pergebat hrc Cometa’ per figna’ fere novem, a Virginis<br />

Micet duodecimo grad11 ad principium Geminorum, prz:-<br />

ter fignunl Leonis per quod pergebat aniequam videri coepit : &<br />

nulla alia extat Theoria, qua Cometa tantam Coeli partem motu<br />

$regulari percurrat. Motus ejus fuit maximc inzquabilis. Nam<br />

circa diem vigefimum -No~mbris, defcripfit gradus circiter quind<br />

que fingulis diebus* dein motw~ retardato inter Nocvemb. 26 8~<br />

Decenzb. 12, @at+ Ccilicet dierum qtiiridecim cum fkmiffe, defitipfit<br />

gradus tantum 40 ; pofiea vero ‘motu iterum accelerate,<br />

dcfcripfit gradus fere quinque hgulis diebus, antequam motus<br />

iterum retardari coepit. Et Theoria quz motui tam inaequabiii<br />

per maximam’coeli partem probe refpondet, quzque eafdem ob-<br />

&vat Ieges cum Theot;ia PianetBrum, & cum’ accuratis obfervationibus<br />

Afirorxomicis accurate congruit, non poreft non effe Vera.<br />

cometa tameti cub finem motus dekiabat aliquantulum ab hat<br />

TrajeBoria Parabolica verfus axem Parabolas, ut ex erroribus mi-<br />

.


i<br />

;’<br />

*<br />

_.<br />

_


liptic0 circullt Solan movebatur, [patio annorLIm plu~qualII q~&~<br />

L 1 li F. It<br />

&catar”n% qu~l~ltLl~l1 CX erroribus i&S judicare licuit, revolutio- ‘I‘ LIN I us.<br />

nem peragw.<br />

CiJ333W~ Traje~koriam Guam &meta defcripfit, & ~~~~~~~<br />

veram qua1-n fingulis in lock projecit, vifum efi annexo fc~chenIatc<br />

in piano Trajeeorirx: optice delincatas exhibere: C)bfervarionibus<br />

fC’eqUetltlbus in Cauda definienda adhibitis,<br />

L\Tpv* ‘7 Cauda gradus amplius quindecim Ionga ~onfbdo aypWl1t.<br />

NW. 18 Cauda 3ogro lollga, Solique dire&e oppofita 111<br />

N~va-.AcgZis cernebatur, k protendebarw uf?que ad ReIIam 6 ,<br />

(1UX! tUllc crat in ?P per* 54’. Non 19 in Mary-land cauda vih.<br />

fitit: gradus I 5 vel 20 1011g3. Z)CC,IO Cauda (obfcrvante I;la~$e&a)<br />

tranfibat per medium difkantiaz inter caudam fcrpentis Ophiuchi k<br />

Bellam 2 in Aquilx aufirali ala, & definebat prope fiellas A, &, b in<br />

Tabulis Bdyeri. Terminus @icur erat in VP 19$grm cum faticu&Ile<br />

boreali 34: 6’* circiter. CDN. 11 furgebat ad ulque caput Sagirtx<br />

(Bdycro, a, @,) dcfinens in w 26~” &3’, cum latltudine boreali<br />

38 gr* 34’. DEC, I z trnnfibat per medium Sagittz, net longe ultra<br />

protendebatur, definens in z 4P, cum laticudine boreali 42:~ circirer.<br />

lnteltigenda funr ~XX de longitudine caudaz clarioris, Namluce<br />

obfcuriore, irl c~lo forian ma@ fireno, caudaCDec. 12, hora 5, 40’<br />

Rorn~~ (r>bfervante “Ponth~o) ii3pra Cygni Uropygium ad gradus IO<br />

fek ixtulic j argue ab hat fiella ejus latus ad ~ccdiim & boream<br />

min. 4~ dcfiitit. Lata autem erat cauda $is dlebus gradus 3:, juxta<br />

,terminum {uperioretn, idcoquc medium ~&IS diltabac a Stella illa<br />

2 I2 35’ a&rum verfus, & terminus firperlor erae 111 M 22 gr* cunl<br />

?atitudinc borenli 6 x 6’~. Dec. 2 I furgebat kre ad cachedram L’&op,+d,<br />

;rqualiter difians a @ 8t $cbedir, Sr difiantiam ab utraquc<br />

djfialy& ear&y ab inviceny Equalem habens, adeoquc d&lens<br />

jn 3t 24, ~6 c~tm latitudinc 471 gr*. r~)ec. 29 rangebat Jkhetit fitam ad<br />

Gniaram, & intervallum fielkwum .duarum in pede boreali Atidr~m&d<br />

acc’~~rato complebat, & longa erat 5+B” adeoque, definehat<br />

in 8 z 9 w cum Iatitudine 3 5@9 J&G, 5 ret@ fieflam * 111 peaore<br />

&&ronaedd, ad latus finm dextrutn, F +ellam ru in ejus cinE$o<br />

ad Iatus Gnifirnm ; & (juxta QbkrvatlolIeS nofiras) loll@ em<br />

40 P-’ ; c’Llrva alItem crat sr: convexo Iatere fpe&abat ad a&rum*<br />

cum circulo per Solem Eh caput Cometa tranfeunte ?Wlum<br />

confecir gra&tunl 4 j,xta caput: COlYletx; at Juxt2 termmum a1-<br />

$erUm illc]jnabatur acf circUlum jllUm in ?ngulo X0 vf r I graduum,<br />

&: &or& caudg cum circuIo;lipo contlnebat angulum grad:;7<br />

0


I ‘)I: h,l v N LiI oc&(). yELi~. 13 CaLIda lute filtis fendibili ccrminabatur inter Alas<br />

YSTE”*iT’: adi”c.~, k A&Q~, ‘q l~lce tenuiOima dcfincbat c regione itelk H. in<br />

lacel-c Yfbp. ~);f~:mtia termhi caudx 3 circulo Solem & Gomeram<br />

ll-2 lgwre cr.lf 3 51, 50’, & inclinatio chords caud:z ad circulum<br />

1llurn i;:"? . fan. 25 & 26 lute tenui micabat: ad longitud~ncm<br />

~raduum 6 vel 7 ; k ubi co=lum valde ferenum erats luce<br />

r~,1uitfi&;~ EE ayerrime itnlibili attingebat longicudinern graduum<br />

duodecim Cs paulo ultra. Dirigebatur aucem ejus axis ad kucidanl<br />

in humero oricnt:lli Auriga accurate, adeoque declinabnt ab<br />

oppoficiollc Solis boream verfils in angulo graduum deccm. Del~ique<br />

B;;$, 1o Cnudam oculis armatis afpexi gradus duos lon-<br />

CPLlrtl. Nam lux przdifia tenuior per vitra non apparuit. ‘Pan-<br />

L%:PCS autem .F&. 7 k caudam ad longitudinem graduum 1 P<br />

vidiIk ii-ribit.<br />

Orbem jam defcriptum @e&anti & reliqua Cornet2 hujus Fhaznomerja<br />

in’ animo revolvenri, haud dificulrer confiabit quad corpora<br />

Comerarum fine folida, compafia, fka ac durabilia ad in-<br />

Oar corporum Planecarum. Nam ii nihil aliud effenc quam vapores<br />

vel exhalationes Terriz, Solis S= Flanetarum, Cometa hicce in<br />

tranlitu fuo per viciniam Solis fintim diOipari debuiffkt. Efi enim<br />

calor Solis UC radiorum deniitas, hoc efi, reciproce ut quadratum<br />

difiantiaz locorum a Sole. deoque CLW difiantia Cometaz a tenzro<br />

Solis ‘Decemb. 8 ubi in Perihelia verfabatur, effet ad difianoiam<br />

Terra a centro Sulk ut 6 ad IOOO circiter, calor Solis apud<br />

Cometam eo cempore erat ad calorem Solis azfiivi apud nos ut<br />

~oooooo ad 36, feu 280~0 ad I. Sed calor aquz.ebullienris edt<br />

quafi rriplo major quam calor quem terra arida concipit ad z&i-.<br />

vum Solem, ut expertus f’um: & calor ferri candentis (fi re&e<br />

conjeQor) quail triplo vel quadruple major quam calor aqux ebulkentis<br />

; adcoque calor quem terra arida apald Comctam in Perihelio<br />

verfincem ex radiis Solaribus concipere poii’er, cluafi 2000<br />

vicibus major quam calor ferri candentis. Tanto autem calore<br />

wapores & exhalatlones, omnifque materia volatilis fIatim confumi<br />

ac diGpari debuifint,<br />

Cometa igitur in PeriheIio fllo calGem immen~um ad Solem<br />

concepit , & calorem illum diurifime confervare potefi. Nam<br />

globus ferri candentis digitum unum latus, calorem [uum omnem<br />

ikatio horn unius in acre confiikens vix amitteretl Globus autem<br />

major caiorem diutius conkrvaret in ratione diametri, propterea<br />

quad fi~gerficies (ad cujus menfiwam per contaRum aegis ambientis


I<br />

fm% refrigeratur) in illa ratione minor efi pro qlItantitarc Ill;tca 1,: ?. x<br />

~iae ha: calidre inclufk ldeoque globus ferri calldcntis /laic ‘r~*’ : 6 is<br />

‘I’erra aquaIis> id efi> pcdes PIUS minus ~oocoooo ~a;Icljs, dicl>us<br />

totidem, & idcirco annis 50000, vix rcfrigefceret, Su+icor ramen<br />

q”od duratio Caloris, ob cauEls laterItes, augeatur iI1 nllnorc<br />

ratione quam ea diamerri: k optarim rationem veram per cxpcr:-<br />

menta inveltigari.<br />

Porro notandum elE. quad Comeca ~c~~re ~~~~~~~~~~~ ubi aEi<br />

Snlem modo incaluerat , caudam cmittebat longe majoren ZC<br />

fplendidiorem quam antea Menk iYVuw~h+, ubi perihclium nondum<br />

attigerar. Et: uk.vcrfalitcr caudz omnes maximn: e; fLllgcI”-<br />

tifl?mz e CorllcXiS oriuntur, fiacim pofi tratlfitu:n eorum i>er re$-.<br />

onem Solis. Conducit igitur calefaaCcio ~omera ad ~~a~niru~illem<br />

caudx. Et inde colligere videor quad cauda Ili]$l aliud tit<br />

quam vapor longe tenuifimus, quem caput f&2 ~cleu~ CQWX<br />

yer calorem hum emit&.<br />

Chterum de Cometarum caudis triplex efi opinio; cas vel jubnr<br />

eire Solis per tranflucida Cometarum capita propagatum, vel oriri<br />

ex refraeione luck in progreffu iphs a capite Cometll: in Terram,<br />

veI denique nubem efre feu vaporem a capite Comertl: jugiter<br />

{urgentem & abeuntem in partes a Sole aver&L Opinio prima<br />

eorum efi qui nondum imbuti funt i’cientia rerum Opticarum.<br />

Nam jubar Solis it1 cubiculo renebrofii non cernitur, nifi quatenus<br />

lux refle&itur e pulverum Sr fumorum particulis per aerem kmper<br />

volitantibus: adkoque in aere fumis crafioribus infefio fhn-<br />

&dius &, & ienfum fortius ferit; in aere clariore tenuius efr: &<br />

3zgrius fkntitur : in &is autem abfque mareria reflefientc nullurn<br />

effe potefi. Jiux non cernitur quatenus in jubare et?, f’cd quatmus<br />

i&e refle@--tur ad oculos nofhos, Nam vifio IIOII fit nifi per radios<br />

quiin acu]os impingunt. Requiritur igitur materia aliqua rcfie&kns<br />

in regione caudz , ne celum totum lute Solis illufiratum uniformiter<br />

fplendea t. Opinio fec.unda multis premitur difficulratibus.<br />

caudz nunquam varkgantur coloribus : qui tamen refratiionu?<br />

iblent ege comites infeparabiles, LUX Fiyarum Sz: Plalletaru? diainae<br />

ad no++ tranf’liffa, demonfirat medium c&efie nulla v1 refra@iva<br />

pollere. Nam quad dicitur Fixas ab &gyp!fzs comatas<br />

n!onnunquam vihs fuifi,<br />

id quoniam rarifflmc COntl~~@t~ d&ibendum<br />

ea Ilubium refra&ioui fortuitz. Fixarum quoque .radiatie<br />

& fcintillatio ad refraaiones turn ChXlorum turn Aerls tremn~i<br />

referend% funt: quippe quz admotis ocuh Tele~~~I?$~<br />

000 2 L


SJ~ MLJNIJ~ Wallehmt, Aegis & akendentium vaporum tremore fit ut radii<br />

~YSTEM*TJZ facile de anguilo pupilk {patio per vices detorqueantur, de latiore<br />

aurem v;tri objehivi apercura neutiquam. lndc efi quo&<br />

fcinti\/atio in priori calh generecur, in pofieriore aurem ceiret:<br />

B;S ccif>tio in pofleriore caPi demonfirat regularem tranCmiGonem~<br />

lucis per ce,.los abfque omni refraLhone knfibifi. Nequis contei-,dLat<br />

Ll:i()d C~LK!X non fokant videri in Curneck cum eorum lux,<br />

paon cr] faris fortis, quia twnc radii iecundnrii non habent fitis vi-<br />

I-ium ad oculos mowndos, & propterea caudas %‘ixarum ncan cerni :<br />

ccieladum efi quad lux Fixarum plus centum vicibus augeri poteiac<br />

rnedianaribus Telekopiis, net tamen caudz cernuntur. Planera-<br />

JXJ~I] qutique ILW copiofior efi, caudze vero nuke Comet= autem<br />

Ikpe caudatifllmi Cht, ubi capitum lux tenuis eti & valde obtuca:<br />

fit enim Cometa tanni 1680, M&e DecembTi, quo tempore caput<br />

]uce ha vix zquabac dtellas fecundz magnitudinis, caudam<br />

emittebat Cplendore notabili ufque ad gradus 4~ 50, GO loalgitu$~n~s<br />

& ultra: pofiea JLW. 27 & 28 caput apparebat ut fiella<br />

feptlms rnncum magrlitudmis , cauda vero lucc quidem pertcnui,<br />

fed Otis ienfibili longa erat 6 vel 7 gradus, Sr lu~e obkuritlima,<br />

quz cerni vix poffet, porrigebatur ad gradum urque duodecimurn<br />

vel paulo ultra: ur fiipra di&tum efi. Sed & F&. p & IO u bi<br />

caput -nudis oculis videri defierat, caudam gradus duos longam<br />

per Tclefcopium contemplatus film. Porro fi cauda oriretur ex.<br />

refra&ione materiaz ccelelh, & pro figura ccelorum defl.e&eret,ur<br />

de Solis oppofitione, deberet deflexio illa in iifdem cozli regionibus<br />

in eandem femper partem fieri. Atqui Cometa Anni IQ~O<br />

‘Becmb. 28, hora 85 P. M. Landini, verfabatur in x 8~~. 4~’ cum<br />

latitudme boreali z8fir* 6: Sole exifknte in VT 18gr- z6’, Et Cometa<br />

Anni I 577, DC. zp verkbatur in 3f 8gr. +I' cum lathdine<br />

boreali 28 gr- 40'~ Sole etiam exiitente in VP I 8 gr* 26' circiter.<br />

Utroque in cafii Terra verijbatur in eodem loco, & Co..<br />

meta apparebat in eadem coeli parte : in priori tamen cak cauda<br />

Comet% (ex meis & aliorum Obfervationibus) declinabat angulo,<br />

graduum 45 ab oppofitione Solis aquilonem verbs; in pofieriorc<br />

vero (ex Obfervarionibus Z(ychmis) dechatio erat graduum<br />

21 in auhum. lgitur repudiata ccelorum refraQione,.<br />

bilperefi ut Fhnomena Caudarum ex materia aliqua refle&ente<br />

deriventur.<br />

Caudas autem a capitibus oriri & in regiones a Sole averfis<br />

akendere confirmatur ex legibus. quas obG-ervant, WC quad in<br />

planis


PIUNCIPIA ~EMATXX. $9<br />

planis ChiiLlm Cpmetarufn per Solcm trankuntibus jacentes, de- ~~~~~~~<br />

viant Clb Op~OGtlOnC SolIS 111 cas hnpcr partes, quas capita in TERT[U-L<br />

@+ibus illis progrcdlcntia rehquunt, Quad @e&tori in his<br />

yhis oanititllto apparelIt in partibus a Sole dir&e averfisj dis<br />

grediencc. autCIll f@Qatorc de his planis, deviatio paulatim iknfitW,<br />

SC iudics nyparet major. C&d deviatio czteris paribus<br />

minor cfi ubi cawh obliqtlior cfi ad Orbem CO1netx, uc 8~ ubi<br />

l.XlpUt COllletLC ad. SOl~[ll prOpiLlS accedit j prxfcrtim fi $f-&ctur<br />

deVi~ltioI.Iis allgLliUS jLlXta caput Cometz:. Pr;rterea quad caild;r:<br />

plan deviantes appnrwt w&i?, dcviantes aurcm incurvantur, Qllod<br />

CUTV~;~EUIYL rnaj~r et-k. ubi major efi deviatio, &. magis fenfibilis ubi<br />

cauda cztcris paribus lor~gior efi: nam in brevioribus curvatura<br />

regre animadvcrtitur+ Qod dcviacionis angulus minor efi j,xta<br />

caput @omct;er major juxta caudaz extremitatetll alteram, atque<br />

adco q~xod cauda CO~VCZXO fui here partes re@icit a qLlibus fit.<br />

deviatio, quzcque in rcEt-a hnt linen a Sole per caput Comet= i.n<br />

infinitu111 du~ta. Et q”od caudz ~I.LE prolixiores hunt k latiores,<br />

‘& lucc vegctiol*e micant, fint ad latera convexa p&o f+lendidiores<br />

& lirnitc minus indifiin&o terminate quam ad concava.,<br />

Pendent: igitur Phznomcna caudz a motu capitis, non autem a.<br />

regionc cceli in qua caput con~picitur ; & proptcrea non fiunc per<br />

~fdlkm3 t20210rum cccl a capite fuppeditante materiam ori-:<br />

untur. JEtenim ut in Aere nofiro fumus corporis cujufvis igniti-g<br />

petit fhpcriora, idquc vel perpendiculariter ii corpus quiefcat,<br />

vel oblique fi corpus movcatur in Xatus: ita in Cc&s uti corpora,<br />

gravitallt j1-1 S&m, Fumi St vapores afcendere debent ;.Sole (uti<br />

Jam di&um efi) & hpcriora vel r&a petere, fi corpus fumans,<br />

quiefcic s vel oblique, fi corpus progrediendo loca kmper ,deferit.<br />

a quibus fllperiores vaporis partes akenderant. IZF obliqultas $a.<br />

millor Grit: ubi afcenfus vaporis vcloctor &I: nimlrum In Vlcfllld<br />

Solis & juxta corpus FU~n~lX~ Ex obliquitatis autem diverkate<br />

incurvabitur vaporis columna : & quia vapor in columnrx: latere.<br />

prscedcate paulo recelkor efi9 ideo etiam is ibidem aliquanro<br />

deilfiar erit, Jucenlque propterea copiofius rcfle&eh & lirnite miaus<br />

indifiin&o tcruhabitur. De Caudarum agitionlbus fubita-,<br />

ncjs & inccrtis, deque earurn figuris irregularibus~ quas nOnfiUlh<br />

quandoque dekribuut~ hit nib11 adjicio; propterea quad vel a,<br />

mutarionibus Aeris nofiri, & lnotibus nubium caudav aliqua ex+<br />

parte obfiuramium orianty 5 vel forte a partibus Vi32 La&te;c,<br />

qug CurII c3udis pr~tcrewnthls conhndi plant,. ac tanguam W*<br />

Vapprum<br />

partes fpC&Wi+


~-<br />

q. - 3<br />

t’ L P~--IIEOSOPWIX NATURALIS<br />

I’ 1 ?* \ t 4 >,‘i> 1 1’2porcs autern, qui f-patiis tam irnmenGs implcn,dis G.~uflficial:r,<br />

.: ’ - ’ “‘.’ I“ cx C~omccnrum Armol-ph~ris oriri pore, intelligetur cx Raritan<br />

Act-is nofiri, Nam Acr juxta fiperficiem Terrs i@tium occupaC<br />

c]u;lii S $0 partibus majus quam Aqua ejufdem ponderis, idzoquc<br />

Acris columna cyllndrica pcdes 8~0 alta, ejuklem efi ponderis<br />

a:um AC~UX columna pedali latituclinis cjui‘dem. Columna autem<br />

/Icris ad ~i~nmmitatcm /Itmoiphzr:tz aKurgens ~ztqua~ pondere iiso<br />

colum~am thqus pcdes 33 altam circiter ; Sr propterea fi col~m-<br />

112 torius Acrcx pars inferior pedum 8fo altitudinis dematurr<br />

pars rcliqw Ciperior squabit pondere Cue columnam Aqua altam<br />

pedes 32. lndc vcro (ex HypctheG mulris experimentis confirmata,<br />

quod compreilio Aeris iit ut pondus Atmofphazrz incaambentis,<br />

quodque gravicas fit reciproce ut quadraturn diflantia Pocorum<br />

a centro Tcrraz) cornputationem per Corol. Prop. XxIE.<br />

Lib. II. incundo, inveni quad Acr 9 fi aicendatur a fkperficie<br />

‘Ferrz ad alritudinem i&midlametri unius terrefiris, rarior Gc quam<br />

spud nos in ratione longe majori, quam fpatii omnis infra Orhem<br />

Saturni ad globum dlametro digiti unius dckriprum. ledeoque<br />

globus Aeris noltri digitum unum lacus) ea cum raritate<br />

quam ha beret in altitudine femidiametri unius terreltris, impleree<br />

omnes Planecarum regiones ad ufque iphzram Saturni & Ionge<br />

ultra. Proinde CUM Aer adhuc altior in immeslfiun rarekat; 8~<br />

coma feu Atmofphtura Cometz, akendendo ab illius centro, quail<br />

dccuplo altior iit quam fiperkics lluclci, deinde ca,uda adhuc<br />

alcius aicendat, debebit cauda effe quam rarifima. Et quamvis><br />

ob longe crafflorem Cometarum Atmof’hazrams magnamque corporum<br />

gravitationem Solem verfus, & gravitationem particularum<br />

Aeris Sr vaporum in Ce mutuo, fieri poffit ut Aer in fpatiis<br />

ccelefiibus inque Cometarum caudis non adeo rarekat; perexiguam<br />

tamen quantitatem Aeris & vaporum:, ad omnia illa caudarum<br />

Pht~nomena abuude fufficere, ex hat computatione perfpicuum<br />

cit. Nam & caudarum infignis raritas colligirur ex afiris<br />

per eas cranflucentibws. Atmofpbara terrefiris Iuce Solis @Iendens,<br />

craflicudine ka paucorum milliarium, k afira omnia & ipfim<br />

Lunar-n obfcurat & extinguit penitus: per immenram vero<br />

caudarum crafitudinem, lute parker Solari illuflrntnm, aRra nainima<br />

abfque-,claritatis detriment0 tranflucere nofcuncur. E\JHp~<br />

major. etle folet caudarum plurimarum Splendor, quam Aeris nofkri<br />

in tenebrofb cubiculo latitudine digici unius duorumve, lucem<br />

Solis in ,jubare refle&entis. .,.


Q1.0 temporis @ati0 vapor a capicc ad terminum calldz afccnw 1<br />

dir, wgnoki he pot& duccndo re&m a tcrlnino cauda 3d saw *I’ !‘#: ;I)<br />

JelX, (s; rmtando lOCULl ubi reQa ilIa r~rajeL~“rian~ fccAt, Nam<br />

vapor in tqnlino cmd;r, fi refki afcelldar a sole, al:cnderc cCCPix<br />

a capice CjluO rempyre caput erat in loco interik&io~lis, ri~ vnpGr<br />

non reBa akendic ZI Sole, kd motum Comct;-u, quem ante a+rafun-r<br />

ilium J=bebar, retinendo, 8r cum nzotu arcclafL]s Gli cL1ilC~CIll<br />

componendo, afcendit oblique. f_Tnde verior erit Probtcmnt~s<br />

fulu~io~ ut reEka illa quz Orbem fecat, parallela fit longitudini<br />

cauck, vel potius (ob muturn curvilineum Cometx) ut c&m a<br />

linea caudz divergat. k-h patio invcni quad vapor qui crac in<br />

termino caudlz: yan. 2~~ akendere cozperat a capite ante ~DPC. 11,<br />

adeoque afcenfu iilo toro dies plus 47 confim~pkr~~t. At cauda<br />

i1l.a omnis quz “Dec. IO apparuit, afcenderat fpatio c&rum illarum<br />

duorum, qwi a tempore Perihelii Comertr: elapii fucraa~,<br />

Vapor igitur fub initio in vicinia Solis cclerrime afcendebat, &<br />

paitea CUM motu per gravitatem Guam f&per retardate afcendere<br />

pergebat 3 8r afcendendo augebat longitudinem caudz : cauda<br />

.autem quamdiw apparuit ex vapore fere omni corkbat qui a<br />

ternpore Perihetii afcenderat j & vapor) qui primus akcndit, &<br />

:ce’minLlm caudk compnfi~ir, nan prius evanuit quam ob nimiam<br />

fuanl tam a Sole illufirante quam ab oculis nofir& difiantiam videri<br />

defiit. Unde &am cauds Comcrarum diorum qUZ breves<br />

.funt, non a&?cendunt motu celeri & perperuo a capitibus 8~ mox<br />

evanefcunt, fiid funy: permanentes vaporurn 8~ exhakionum COlumnz,<br />

a capitibus lentiffkm multo~um dierum motu prqagat%<br />

‘PuE, partdcipando motum illum capltum quem habucre fub initiop<br />

per c(x\o~ una cum capitibus moveri pergum. Et $nc ry-iis Cdligitur<br />

fpatia caleeia vi refiftendi deltitui; ntpote In quibus nap<br />

folum folida Planetarum & Cometarum corpora) fed ctkm rar$<br />

Fiji c-u&rum vapores moEus fuOS VdOCifimCB bXri~~ p’ragullE<br />

ac diuti@me ecdervanc.<br />

Afcenfum caudarum ex Atmof’phyris capitum & progrefium in<br />

partes a Sole ayerfas Keplerzts afcriblt a&ion1 radiorum * lucis mareriam<br />

caudae fecum rapicntium. Et auram Iongc tenu&knam 111<br />

fpatijs 1iberrimi.s a&ioni radiorum cedere,. non eit a fatior,! .prorfis.<br />

alienu,m, non obelante quod fubfiantr3: crarz, m~pedmGiml.s<br />

in regiwibus noi’ris, C 1 radiis Solis Cenfibiliter propel11 nequeant,<br />

Al& particulas tam leves quam graves dari PO@ ~~~~~~~~e~<br />

- nqateriam cau&gwn kvitare, perque kvltatem fuam<br />

derc,


‘i)~ nlusnl derea Cum autem gravitas corporum terrehium -iit ut materi:u.<br />

S~STLXATE .<br />

,m corporibus, ideoque<br />

I<br />

krvata quanticate materlz mtendi & re-<br />

.mitti nequeat , iiafplcor afcenfum illum ex rarefa&ione materi<br />

caudarum potius oriri. Akendit fumus in camino impulfu Aeris<br />

,cui innatat. Aer ille per calorem rarefaQus akendit, ob diminutam<br />

fuam nravitatcm fpecificam, SC fumum implicatum rayit k-<br />

~CUlll, Quihdni cauda Comets ad eundem modum akenderit a<br />

Sole? Nam radii Solares non agitant Media qu:r permeant, nifi<br />

in reflexionc ik refraQionel articulaz refleaentes ea a&one calefa:dQz<br />

caleElcient auram zetheream cui imphcantur. Jlla calore iibi<br />

communicate rarefiet 3 & ob diminutam ea raritate gravitatena<br />

[ilam Cpecificam qua prius tendebat in Solem, akendct &C kcum<br />

rapjet particulas refletientes ex quibus cauda componirur : Ed<br />

afcenfijm vaporum conducit etiam quad hi gyrantur circa Solem<br />

& e;l a&.ione conantur a Sole recedere, at Sob Atmofphxra ,&<br />

-mat&ia calorum vel plane quiekit, vel Pllotu folo quem a Solis<br />

rotatione acceperin t9 tardius gyratur. Eke filnc cauh afccnfus<br />

.caudarum in vicinia Solis, ubi C.hbes curviores iunt, & Cometx<br />

intra denfiorem 8~ ea ratione graviorem Solis Atmofphzram confiltunt,<br />

& caudas quam longiff’mas mox emitrunt. Nam cauda:<br />

,quz tune nafcuntur, conhvando motwm fimm & interea verbs<br />

Solem gravirando, movebuntur circa Salem in Ellipfibus pro<br />

more capitum, Sr per motum ilium capita fernper comitabuntur<br />

& iis liberrime adhxrebunt. Gravitas enim vaporum in Solem<br />

non magis efficiet ut caudaz pofiea decidant a capitibus Solem ver-<br />

.&us, quam gravitas capitum efficere podit UC ilax decidant a caudis.<br />

Commuaai gravitate vel fimul in Salem cadunt, vel fimul in<br />

afienfil &JO recardabuntur ; adeoque gravitas illa non impedit,<br />

.quo minus caudz St capita pofitiollem quamcunque ad invicern a<br />

caufis jam defcriptis, aut aliis quibukunque, facillime accipiant &<br />

goitea liberrime fervent.<br />

Caudx igitur qux in Cometarum eriheliis nakuntur, in regiones<br />

longinquas cum eorum capitibus abibunt, & vel inde poit:<br />

longam annorum kriem cum iifdem ad nos redibunr, vel potius<br />

,ibi rarefa&x paulatim evanefcent. Natn pofiea in dekxnTu capigum<br />

ad Solem cauck Y-IOVZ breviukulx lenro motu a capicibus<br />

unt, & fubinde, i heliis Cometarum illorum<br />

mofplzram Solis ndunt, in immenfium aunim<br />

in i’patiis illlis liberrimis perpetuo rarekit ac<br />

a ratione fit ut cauda omnis ad extremitatem hpesiorem


_<br />

riorem latior fit quam juxta caput Cometx, Ea autem rareE&i- LlkSltN<br />

Olle V~~~iTlll pClJX~U0 dilatatum difFufl& tandem & fpargi per Tr;aTIus.<br />

CO%S unlverfh delndc paulatim in Planetas per gravitatenl fuam<br />

atdli 8~ CLUI~ CO~LIIII Atmofpha~is mifceri, rationi confentaneum<br />

videtllr. J?Janl q~~emadmodum Maria ad ConfiitLJcionem Tcrr;c<br />

hujus 0EDnino requiruntur ) idque ut ex iis ‘per cal~rem Solis vat-<br />

Porch capiofi hki cxcit@ntur, qui ~1 in nslbes co&i d&&rlt<br />

in plaviis, 8~ ~CITW~ O~IIPIC~II ad pr.ocreationem vcgccabilium irrigent<br />

St IlLIWi~llt: j ~1 if1 fri$idis montium verticibus condenfati<br />

( ut aliqui cum ratione philofophantur > decurranc in fontes &<br />

flumim : fit ad confcrvationem marium Sr: humorum in J?~~~~I$,<br />

requiri videntnr C.bmetx~ ex quorum exhahtioylibus 8~ vaporibus<br />

condeni~tis, quicquid liquoris per vegetationem & putrcfa&ionein<br />

confumitur & in terrarn aridam convertitur, continu0<br />

fippleri & r&i poflk, Nam vegctabiiia omnia ex liquoribus<br />

omnino crefcunt, &in mag%a ex park in terram aridam per pu4<br />

trcfa~ionem abcunt, & Iimus cx liquoribus putrefX2is perpetuo<br />

decidit. Him n~oIes Terrx arid% indics aagecur, & liquores, nifi<br />

aliundc augmcntum fi~merent, perpetuo decrekcre deberent, ac<br />

tar&m deficcre. Porro fufpicor Spiriturn illurn, qui Aeris nofiri<br />

pars minima efi fed fubtiliffima SC optima, & ad rerum omnium<br />

vitam reqniritur, cx Cometis prz3zipue venire.<br />

Atmo~phazr~ Comerarum in dekccnfil eorum in Solem, e&wrend0<br />

in caudag diminuuntur, & (ea certe in parte quz Solem<br />

refpicit) angufiiorcs redduntur : & viciffim in rcceiru eorum a<br />

Sole, ubi jam minus excurrunt in caudas, ampliantur ; ii mod0<br />

Phanomena eorum EL~ve,?iziGs rc&e notavir, Minimrr: autem apparent<br />

ubi capita jam modo ad Solem calefa6kt in caudas maximas<br />

& fulgexatifimas abiere, & nuclei fumo forfin crafiore & nigriore<br />

in AttnoCphzrarum partibus infimis circundantur. Nam fllmus<br />

omnis jngenti ealorc excitatus, craflior & nigrior effe fokt. Sic<br />

caput Comets de quo egimw in zqualibus a Sole ac Terra diflantiis<br />

Obfcurius apparuit pa,@ Perihelium fuum quam anten.<br />

h/fenfe &im ~)yem.& cum fiellis tertk. mae;nitudinis conferri Cole-<br />

bat,. at JJ&ZYI~P: i+Gmwalz~i am fkllis prima: & ficund=* El: qui<br />

u.tramq+klc viderant, majorem dekbunt Cometam priorem. &/am<br />

Javcni cui&m ~~fl*&~@+fly?, Nowemb. rg, Cometa l-&e he .fk .<br />

quantunlvis plumJ>ca, & obtufar zquabat Spicaln Virgin& 8~ clarius<br />

micabar quam pofiea. EC “D. $tarer literis qua: in manus no-<br />

fi,ras -&i&r@, fcripfir caput ejus Menk Decemdri, ubi caudam<br />

PPP<br />

I-LllaXl-


474 FHILOSOPHI~ NATURALIS<br />

116 ~~IJ~:DJ maximam & f+cntifGmam emittebat, parvum efi & magnitu-<br />

SrSTE’SIATEdine vifibili longc cedere Comer;L, qui Menfe ~ovrrwbri ante<br />

Solis ortum apparuerat. Cujus rei rationem eKe conje&abatur,<br />

quad materia cayi s iiib initio copiofior CfGt, & paulatim con-<br />

Eumercrur.<br />

Eodem @e&are vidctur quod capita Cometarum aliorum, quB<br />

caudas maximas & fulgentil’knas emikruot, apparuerinc hbobfcura<br />

& exigua. Nam Hnno 1668 A!i~~rt. y, SC. nov. hors kptima<br />

vefpertina R. P. Vahtz’nus EJZa~xi~~s, B~Lz$Z& agcns, Cometam<br />

vidic fjorizoiiti proximum ad occahm 5011s brumalem, capiee<br />

minim0 12 vi:: com~pkuo , cauda vero fupra modum fulgente, ut<br />

ftantes in littore ipecicm ejus e mari reflexam facile cernerenr.<br />

Speciem utique taabebat trabis fjlenden tis longitudine 23 graduum,<br />

3b occidente in auhum vergens, & Horizonti fere para-<br />

Ma. Tantus autem fplendor tres iblrum dies durabat> fibinde<br />

llotabiliter decrekens; 6--z interea decrefiente fplendore autia efi<br />

rnagnitudinc cauda. Unde etiam in CYort~~gaZZikz quartam ferc<br />

co$ partem (id ef?, gradus 4-5) occupaffe dicltur, ab occidente in<br />

oricrltetn fplendore cum infigni protenfa; net camen rota apparuits<br />

capitc kmper in his regionibus infra Horizontem delitekente.<br />

Ex increment0 caudz Sr decremento fplendoris manifefium efi<br />

quad cayut a Sole recefk eique proximum fuit iilb initio3 pro<br />

more Cometz anni 1680. Et fimilis legitur Cometa anni I 101<br />

vel 1106, c~jjus SteZZu erdt psrva & obfcwa (ut iile anni 1680)<br />

fed /phk.hr qui ex en exivit valde chw & qz/afi ingens trabs &<br />

Urie~2tsna & Aqdomm tendebat, ut habet HN.VZ~MS ex $jmesne<br />

BzlngZmenJ Monacho. Apparuit initio Nerds Februarii, circa ye--<br />

fperam,ad occahmSolis brumalem. Me vero 8~ ex fitu caud~t:~lligitur<br />

caput fuiffe Soli vicinum. A So& inquit Matchzus Parifienfis,<br />

d$nbat qu+$cubito 8%oJ tib bar& tertia [re&ius lexta] z$<br />

p-de ad hordna nonum rudium ex fe ZOB~UVI emittem. Tabs etiam<br />

erat ardentlflimus ilk Cometa ab A$?otek defcriptus Lib. 1.<br />

Mereor. 6. CY+S capz& prim0 die non conf~eLi%m efl, eo quad ante,<br />

So/em veZ J&m fkb radiis /olaribw occidzret, Jequente vero die<br />

q~~anturn pot&t v%~z~m ej?. Nam qwm minima jeri potep d@unti&:<br />

So/em retiqtiit, & rnox occubzcit. Ob nimiwn ardorem fcauda: fcilicet]<br />

nondtim appdrebat capitis fparfk ignis, fed procedentc tem..<br />

poye (ait Arifioreles) c24m LcaudaJ jam miniw $zgrdret, red&t&.<br />

6~~9 [capiti] Cometi fura fkies. Et Jphzdorem /hm ad tertiam<br />

g&we c&i pardem [ id. efi, ad Go g'*] extendit, AppdrtiiZ uz4tema<br />

temp0;rf


A.7 c I, J<br />

Diximus Cometas en^e genus Planetarum in Orb&us valde cc-<br />

4zentricis circa Solem revolventium. Et quemadmodum e PlanetiS<br />

non caudatk, minores effe folent qui in C)rbibus milloribus &<br />

Soli propioribus gyrantur, fit etiam Cometas, qui in Periheliis<br />

filis ad Solem propius acccdunt, ut plurimum minores eae, nc<br />

Solem attrakkione fua nimis agitent, racioni confentaneum videtur.<br />

Orbium vero tranfverf% diametros & revolutionum tempera<br />

periodic+ ex collatione Cometarum in iifdem Orbibus pofi longa<br />

temporum intervalla redeuntium, determinanda r&quo. lnterea<br />

huic negotio Propofitio kquens lumen accendere potefi.<br />

PROPOSI’I’IO XLII. PROBLEMA XXII.<br />

~per. I. Afilmatur pofitio plani TrajeQoriz, per Propofitio-<br />

@j * zlern fuperiorem Craphice inventa ; & feligantur tria loca Cometa:<br />

-c,. obfervationibus accuratifimis definita, & ab invicem quam maxime<br />

difian tia 5 fitque A tempus inter primam & fecundam, ac<br />

B tempus inter kcundam ac tertiam. Cometam autem in.eorup<br />

,&quo in Perigao -verfari convenit, vel @tern .non longe a Pengao<br />

abeffe. IElx his locis apparentibus nwenrantur, per operaP<br />

tiones Trigonometricas, loca tria vera Comet32 in aGmpt0 ill0<br />

plan0 TrajeBorie. Deinde per loca illa inventa, circa centrum<br />

Solis ceu umbilicum , per operatianes Arithmeticas, ope Prop.<br />

XXI, l[,ib, I, infiitutas, dekribatur Se&i0 Conica : 8-z ejus are%><br />

radiis a Sole ad loca inventa du&is termiuatz, ft1ut.o D 8~ E;<br />

nempe D area inter obkrvationem primam & fkcundam Y Sr E<br />

area inter fecundam ac tertiam Sitque T tempus totum quo<br />

area tot-2 D-+l& velocitate Comets per rap, XVI. Lib. 1. inventa,<br />

defcribi debet.<br />

Oper. 2. Augeatur longitudo Nodorum Plan! Trajebork additis<br />

ad lon&udinem illam 20’ vd 30’~ HUE +~antur p; & firgetilr<br />

plani illius inclinatio d planunl Eclrptlcat Deinde ex<br />

prz==<br />

.PP 2


(Jpfr. 3, Servefur kongicudo Nodorff m in opemtiom2 prima, &<br />

augeacur inclinatio Phi Trajetiorix ad planurn Eclipticaz, additis<br />

ad itlclinlationem illam 20’ ~1 30’2 ~LW dicamtur Q, Deinde<br />

ex obi:rvatis yr;rdi&is tribus Comets locis apparentibus, hve-<br />

~~&:rur jJ1 hoc novo Plans loca rria Vera, Orbiii~uc per loca<br />

.dh erdkns 9 ut & ejufdem arex duz inter obfkrvncioncs dei‘criycx,<br />

qw &It S 4% e, & tcmpus rorum T quo area tota S-/-E<br />

dehibi &beat.<br />

Jam B”at C ad P ur A. ad B, SC 6 ad P ut D ad E, kg ad I ~lt<br />

r;! ad c7 a~ “/ ad 1 ut 6 ad E; fitque S tempus verum inter sMxvaP<br />

EiorIem primam ac rertiam; 84 fignis + & - probe obkrvatis<br />

quxrantur numeri ~fl & Iz, ea lege, ut fit 2 G - 2 C = 132 G - mg -+n<br />

6 --?2-y, & 2T- 7. S zquale 82T --mt+nT--DTr. Er di, in<br />

operarione prima, 1 defignet inclinationem plani Traje&ori,x ad<br />

planurn Ecliptics: 3 & K longitudinem Nodi alterutrius, erit<br />

H -b 1~ Q Vera inclinatio Plani TrajeQorix ad Planurn Eclipticz, &<br />

1~ -~PZ P vera lorlgitudo Nodi. Ac denique fi in operatione<br />

prima, fecunda ac tertia, quantitates R, r & g defignellt Latera<br />

He&a Traje&ori=e, 8i quantitates i> ;,; ejufdem Latera, tranG<br />

verfi refpe&ive : erit +mr-m +n g - n a. verum Larus re-<br />

Qum, & -----I__-.-..<br />

I<br />

.L+mz--YmE+fin--nL<br />

verum Latus tranfverhm Traje&oria<br />

quam Cometa dekribit. Data autem Latere tranfverfo<br />

datur etiam tempus periodicum Comerz ,$$ E. X<br />

Cxterum Cometarum revolventium tempera periodica, & Orhium<br />

latera tranfverh, baud fhis accurate detcrminabuncur, nifi<br />

per collationem Cometarum inter fi, qui dive& temporibus apparem,<br />

Si plures Comets, pofi xqualia temporum intcrvalla,<br />

eundem Orbem dekripfiffe reperiancw ‘J concludendum erit has<br />

omnes effc unum & eundem Cometam, in eodem Orbe rcvolventern.<br />

Et turn &mum ex revolurionum remporibus, dabuntur Orbium<br />

latera tranherh, 8r: ex his hateribus determimhuntur Orbcs<br />

Elliptici,


a Lucida Arietis 1s. 2gm 0 Long. tj, y.24.4~<br />

28<br />

* 7 * 3g 3 Palilicio 2.9’ 37 * 0 Lx. :I, 8.22-f0<br />

--<br />

3’ ’ 6 * 4r a Cing. Androm.<br />

30’ • 43 * 10 Long. ‘d 1. 7.40<br />

a Palilicio<br />

32 73 30 Lx. a. 4.13. 0<br />

_-_I -<br />

7 nn. a Chg. Androm. 2y’IL •<br />

0 Lone;. y 2s .2/f. .47<br />

7 * 7 . 37: a Palilicio<br />

37 * 12 * 25 Lat. bar. o,yL$.. 0<br />

--<br />

24. 7.29<br />

-..-.-,<br />

M&W.<br />

I . 8. 6<br />

I<br />

2 Palilicio<br />

a Cing. Androm.<br />

40’ 9’ 0 Long. I- 26.29. If-<br />

20.32- ‘f Lat. bar. f’.ZJI 50<br />

Comcta ab Hookio prope fccundnrn<br />

I Long. r 29.17.20<br />

Arietis obfcrvabatur, Mar. Id. 711. o<br />

Lat.bQJ. 8*37.lC<br />

Lonilini, c tm<br />

y 20 8 • 20<br />

4’168 2p<br />

Apparuit hit Cometa per men& tres, tignaque fere fix de--<br />

[cripfit, & uno die gradus fere viginri confecit. Curfiis eJUS<br />

a circiifo maxim0 plurimum deffexit, in boream illCW%ItUS j &<br />

mows ejus filb finem ex retrogrado fa&us efk dire&us. Et non<br />

obltante curfu tam iniolito, ? heoria a principio ad finem cum<br />

obfervationibus non minus accurare congruit, quam Theoria<br />

i$l?lanct~rurn cum eorum obkrvationibus congrucrc folent, ut infpicicnti<br />

Tabulam patebit. Subducenda tamen fint minuta duo<br />

prima cirditer, ubi Cometa velociflimus fuit; id quod fiet auferendo<br />

duodecim minuta prima ab angulo inter Nodum akenfku<br />

confiituendo anguIum iIIum ,+ggr*<br />

27’. IV. Cometx utriufque ( & hujus & fuperioris) parallaxis<br />

annua infignis fuits & inde demonfiratur motus annuus Terrx jn<br />

‘Orbe magna,<br />

Confirmatur etiam Theoria per motum Corn&z qui apparuit<br />

anno 1683. I-&c fuit retrogradus in Orbc cujus planum cum<br />

ylano Ecliptics angulum fere refiturn continebat. Hujus Nodus<br />

afcendens (computante HaZZeio) erat in CXJ z3 gr. 23’5 linclinatio<br />

Qrbitlr: ad Eclipticam 83 gr* II’ ; Perihelium in II t5gr* zy’. 30”;<br />

Difiantia perihelia a Sole 56020, exiilente radio Orbis magni<br />

kooooo, & tempore Perihelii JzGi 2“. 3l1, 50’. Loca autem Gomete<br />

in hoc Orbe ab H&deko computata, & cum lock a F&zm-=<br />

,J?e&z’a obkrvatis collata, exhibentur in Tabula kquente.


-m-...--<br />

1683 ;Locus Solis Comcrz Lat. Bar. Comctx Lat. l3or. Differ. I)jgcr.<br />

mp. iEcpL<br />

--.-<br />

Long. Camp.<br />

-<br />

COlllP.<br />

--<br />

Lon,g. Obf.<br />

--<br />

Obfir.<br />

___ Long. Lat.<br />

--<br />

ly.I+- 5 12.35.28 3,=7053 24~24.47<br />

3'. 7.42 18. 7.22 IJ 27.7~. 3 26.22.52 IL<br />

3'.14.55 18.21.53 27.41. 7 26.rG.57<br />

kg, 2.14.56 20.17.16 27~29.32 2~.16.19<br />

6.10. &IO*495, 23.56.45 22. 2.5.0 z3*18.1-0 a+*'".~~ 23.16.55 24.12.19 - 1.25<br />

2~~42.23 22.47. f 20.40.32 22.49e 5 1.,-s<br />

g.10.26 26,5O.f2 16. 7.57 2Q* 6.37 16. f-IS 20. 6.10 - 2. 2 - 0.27<br />

lG,l~.lO If.Ii+. 1 TJ 3.48. 2.47.132 043. 3.30,487 11.37.33 9*34*‘6 3.2G.18 0*4’*lif 11.32, I 2 - 4,30 I.I2 - 0. ?.32<br />

16.If.44 5,4Y.3 3 ti 2‘+P.j’3 5JJ.;” 8 24*4Y- 5 9


DIG. JU u x 1) 1 %libcnturg qeaam f&m mocus klanetarym per corum Theorias, Et<br />

’ i’CT L’lJ’TE propterea Orbes Cometarum per hanc Theoriam esaumerari poi;<br />

lint, &, tcmp~ls periodicurn Comeraz in quolibet prbe revolwentis<br />

tandem fiirl, 6.~ rum demum Orbium Mlipticorum latera tranG<br />

verb & Ayheliorum altitudillcs innotekenc.<br />

Con,xeta retrograduls qui apparuit anno 1607, dckripfit Orbem<br />

cujus Nodus afcendens (computante H~&a’u) erat in 8 ~06’. 21’.<br />

hclimrio plani Orbis ad planurn Eclipticaz erac 17@* 2’. Perihelium<br />

erat in z 2 er* ~(i’, 6r diltantia perihelia a Sole erat 58680,<br />

exiknte mdio Orbis magni IOOOOO. Et Cometa erat in Perihelio<br />

08~4, 16”. 3”. $0’. Coagruir: hit Orbis quamproxime cum<br />

Orbe Comctz qul apparuit anno 1682. Si Cometaz hi duo fuerinc<br />

unus & idem, revolvetur hit Cometa fjatio arrnorum 79+, &<br />

axis major Orbis ejus erit ad axem majorem Orbis magni, ut<br />

$1~: 79~ 7~ ad I, ku 1778 ad 100 circiter. Et difiantia aphc-<br />

&,a Comet;c hujus a Sole, erit ad difiantiam mediocrem Terra: a<br />

Sole, ut 35 ad 1 circiter. @ibus cognit& haud difficilc fuerit<br />

Orbcm Ellipticurn Comets hwjus determinarc. Atque haze ita<br />

. i‘c h;lbebunr fi Cometa, [patio annorum kptuaginta quinque$ in<br />

hoc Orbe pofihac redierit. Comerz reliqui majori tempore revolvi<br />

videntur & altius afkendere.<br />

C3ztcrum Comet33 ob magnum eor&m numerumJ SE ‘magnam<br />

Apheliorum a Sole difiantiam, & longam moram in Apheliis, per<br />

gravitates in fk mutuo nonnihil turbari debent, 6r eorum eccenkricitates<br />

SC revolutionurn tempera nunc augeri aliquantulum,<br />

nunc diminui. Proinde non efi expe&andum ut Cometa idems<br />

in eodem Orbe sz iifdem temporibus periodicis, accurate redeat.<br />

Sufficit G mutationes Nan majores obvenerint, quam qua: a caufis<br />

prazditiis orian tur.<br />

t hint ratio redditur cur Cometx non comprehendantur %odisco<br />

(more Planetarum) kd inde migrent & mot&us variis in<br />

omnes c0.9orum regiones ferantur. Scilicet eo fine, ut in Apheliis<br />

dilis ubi tardiifime moventur, quam longiame difienc ab invicem<br />

& fe mutuo quam minime trahant. Qa de cauk Cornet= qui<br />

altius defiendunt, adeoque tarcMEme xnoventur in Apheliis, debent<br />

altius afcendere.<br />

Cometa qui anno x680 apparuit, minus diftabat a Sole in Peri-,<br />

.heIio cue quam parte kxta diametri Solis 5 & proptei: fi1mmax-n<br />

velocitatem in vicimia illa, & denfitatem aliquam Atmofpharaz So-<br />

&a, rchkntiam nonnullam Centire debuit, & aliquaatulum, tetar.-<br />

LdariJ


ari & propius ad Solem accedere : k IhguIis revolutionibus ac- 1, l i: 7 :,<br />

eledendo ad Solem, incidet is tandem in corpus Solis, Sed R in ~7:: 7 b- I<br />

Aphelia ubi tardiflime movetur, aiiquando per attraaioncm aliurum<br />

Cometarum retahri porefi Sr fubinde in Solem incidere.<br />

Sic etiam StelI32 fix32 ‘qua2 paulacim expiranc in lucem & vapores,<br />

Cometis in ipfas incidentibus refici poflunt, 8;: tlovo alimcnto<br />

accenfz pro Stellis Novis haberi. Vapores autcm qui es SoIc k<br />

St&is fixis St- caudis Cometarum oriuntur, incidere poflitt~t per<br />

gravitatem ham in Atmofplwras Planetarum, & ibi condenihrr.<br />

& canverti in aquam & I-pkrus humidos, & Ctubinde per 1entu:a-t<br />

d-aIorem in files, & fidphura, Ik cirduras, I(r &mum, & lutum, &<br />

argillams & arenam, & lapides, & coralla, & hbitatlrias alias<br />

rerrehes pautatim migrare. Decrefcenre autem corpore Solis<br />

snotus medii Planetarum circum Solem paulatim tardefcent , &<br />

crekentc Terra motus medius Lutz circum Terram paulatim augebitur.<br />

Et collatis quidem obfervationrbus Eclipfium Ba~Gyhricis<br />

cum iis Albategnii & cum hodiernis, HuZIet’w IloiFer motum<br />

medium Lun;e cum motu diurno Terrae collatum, paularim accelerari,<br />

primus omnium quod fciam deprehendit.<br />

Hypotkefis Vorticum multis premitur difficulratibus. Ut PIa.-<br />

neta unufquifque radio ad Solem du&o areas defcribat tempori<br />

proportionales, tempora periodica partium Vorticis deberent efi<br />

in duplicata ratione diitantiarum a Sole. Ut periodica Planetarum<br />

tempora fint in proportione fifquiplicata diltantiarum a<br />

Sole, tempora periodica partium Vorticis deberent efle in eadem<br />

ldifiantiarum proportione. Ut Vortices minores circum Saturnum,<br />

Jovem St alias Planetas gyrati conkrventur & tran.quille<br />

natent in Vortice Solis, tempora periodica partium Vortrcrs So-<br />

Iaris deberent eire zqualia. Revolutiones SoIis & Planetarum circum<br />

axes Cues ab omnibus hifce proportionibus difcrepant. MOtw<br />

Cometarum funt filmme regulares, & eafdem Ieges cum Planetarum<br />

motibus obfervant, & per Vortices explicari nlequeunr.<br />

Feruntur Comet% motibus valde eccentricis in omnes calorum<br />

partes, quad fieri non pockfi nifi Vortices tollantur.<br />

I?roje&ilia, in jere nofiro, folam aeris refifientiam kn tiunt.<br />

Sub]ato acre, ut fit in Vacua ~uyhno, refifientia ceffah. fiqui-<br />

&m pfulna tenuis & aurum folidum zquali CUM velocltate In hoc<br />

Qns<br />

ViClIQ


J)E fij”Nn’ Vacua cadun~. Et par efi ratio fpatiorum cxlefiium quz funt<br />

Srs’rrih’n’rE fupra acmofpharam Terr35 Corpora omnia in ifiis fpatiis liberrime<br />

moveri dcbenc; & propterea Planeta & Cometrr: in orbibus<br />

fpecic & pofitiorle daris, kundum leges fupra expofitas, perpctuo<br />

revolvi. Perfeverabunt quidem in orbhus f..lis per leges<br />

gravicntis, red regularem orblum hum primitus acquirere per<br />

leges hake minime potuerunt.<br />

Planer;e 6x principnles revolvuntur circum Solem in circulis<br />

Soli concentricis, eadem mows direaione, in eodem plano quamprox<br />

ime. Lund decem revolvunrur circum Terram, yovem & Sarurn\ltn<br />

in circuiis concencricis, eadem motus direQione, in planis<br />

orbium Fl:inecarum quamproxime, Et hi omnes motus regulares<br />

originem 11011 habcnc ex caufis Mechanicis 5 fiqu,idem Comets in<br />

Orbibus valde eccentricis, & in omnes cxlorum partes libere<br />

fcruntur. Quo mows genere Cometa per Orbcs Planetarum celerrime<br />

S= facillime tranreunt , & in Apheliis his u bi tardiores<br />

iimt CFX diutius morantur 9 quam longifflme diltant ab invicem,<br />

& i’e mutuo quam minime trahunt. ElegantiGma lwxce Solis,<br />

Planetarum & Cometarum compages non niG confilio & dominio<br />

Entis incelligenris &- potentis oriri potuit. Et fi Stelh fixze fint<br />

centra fimilium fyfiematum ; Ixx omnia fimili confilio confiru&a,<br />

fuberunt UZV’ZU dominio: prsfertim cum lux Fixarum fit ejufdem<br />

nntur,r: ac lux Solis, & fy’yltematn omnia lucem in omnia invicem<br />

immirtant.<br />

Hit omnia regit, non ut Anima mundi, fed ut univerforum Dominus<br />

; & propeer dominium hum Dominus Deus<br />

* Id elt, hpemtor<br />

w?iver/n!is. * ~VTGX&?W~ dici folet. Nam Dew e@ vox relativa<br />

& ad fervos rekrtur : & Dehzs e& dominatio Dei<br />

non in corpus proprium, fed in fervos. -2hs firnrn~~ eR Ens<br />

sternum, infinitum, abfoluce perfe&um; fed Ens utcunque perfetium<br />

fine dominio, non eR 13uminz~ 2%~. Dicimus enim WCNS<br />

meus, 53~~s ueJer, Dezcs IJrmZis : fed non dicimus &?temz~ ~~e.z,w~<br />

uEIernz4s z?eJfpr, bEternfi!J Ifrdclis j non dicimus In$ktttis mew,<br />

Pti$zilz4s ve/fer, ..lt$kitZ4S I/lrraeZis j non dicimus Terf’eAw meus, T~ep<br />

fet7us ueJier, Fofek7m .IJriaeZis. HX appeIlationes relationem non<br />

habent ad fkrvos. VOX TIeus pairrm figaificac %?omhztina, kd<br />

omnis Dominus non efi Dew. Dominatio Entis fpirituaIis 5Yezw.z<br />

conltituit, vera verum, fumma fummum, fit2-a fiQum. Et ex dominatione<br />

vera fkquitur, Deum verum, efk vivum, intejligentem &<br />

potentem j ex reliquis perfetiionibus Summum efi Ve:l fumme perfeErum,


fb%m. MrernsJs eiE 8r: ..hJinitus,<br />

L, D E II<br />

Omnipotens Sr Of&?f$j/cjens, id<br />

efi, &rat ab azterno in sternum & adefi ab infinite in infinitum, TERT,uj.<br />

omnia regit & omnia cognokit qu3: fiunt aut Cciri porunt, Non I<br />

efi azternitas vel infinitas, fed zternus & infmitus; non efi duratio<br />

vd fpatium, fed durat & adefi. Durat fernper & adefi ubique, &<br />

exifiendo fernper & ubique durationem & fpatium, a(ernirarenl<br />

St infiniracem confrituit, Cum unaquzque fpatii particula fit<br />

feirApw, 8~ unumquodque durationis indivifibile momentum &+~ j<br />

certe rerun omnium Fabricator ac Dominus non erit nz17zqzgnlir<br />

nz&@ana. Omniprzfens efi non per zrirttitem folam, fkd etiam<br />

per fii~flantiam : nam virtus fine iitbfiantia<br />

iilbfifiere non potelf. In ipfo * continentur A~l~i~$/~~~~~~z ~JY?r<br />

82 moventur univerfa, fed abfque mutua paf tie, POW in m. 7.27, 28.<br />

l- zone. Deus nihil patitur ex corporum moti- ~;@!~D;;~$;;~;,~;;;;<br />

bus: illa nullam fentiunt refiitentiam ex om- tllDn aeg.;3. t7. $,b. 22.<br />

niprafen tia Dei. Deum fummum ne&&rio 12. ‘feren%m Prophcta ~3.<br />

exifiere in confeffo eit: Et eadem necefitate 23B ‘+<br />

Jhzpet eft & zdique. Unde etiam totus efi Cuifimilis, totus ocuius,<br />

totus auris, torus cerebrum, totus brachium, totus vis fentlendi,<br />

intelligendi & agendi; fed more minime humane, more minime<br />

corporeo, more nobis prorfus incognito, Ut czcus ideam non<br />

habet coIorum , fit nos ideam non habemus modorum quihus<br />

Deus fipientiffimus kntit & intelligit omnia. Gorpore omni &<br />

figura corporea prorfus defiituitur, ideoque vrderi non potefi,<br />

net audiri, net tangi, net fub fpecie rei alicujus corporei coli debet,<br />

Ideas habemus attributorum ejus, fed quid fit rei alicujus<br />

Subfiantia minime cognofcimus. Videmus tantum corporum figuras<br />

& colores, audimus tantum fonos, tangimus tantum ruperficies<br />

externas, olfacimus adores folos, St gufiamus iapores; Intimas<br />

fubfiantias nullo fenfu, nulla a&one reflexa cognofcimu& 8~<br />

nlulto minus idearn habemus fubfiantiae Dei. Hunt cognofci?us<br />

folummodo per proprietates fuss & attributa, Sr per fapientlfimas<br />

& optimas rerum firu&uras, & caufas finales j veneralllur autern<br />

& colimus ob dominium. Deus enim .fine dominio, provident&<br />

SC caufis finalibus, nihil aliud efi quam Datum & Natura.<br />

Et hxc de Dee; de quo utique ex Phanomenis difirere,<br />

ad ~b~~~~~@zrn Experhentalem pertinet.<br />

&&enus Phanomena wlorum & maris nofiri per Vim ravitatis,,ex<br />

ofuiS fed caufam Gravitatis nondum afignavi. 8 ritur<br />

urique, R 8c Vi5 a caufa aliqua 4 etrat ad ufque centra Solis<br />

2 &


lan~tarum9 fine virtutis diminutione; quzque a&r: non pro.<br />

rsTEn’nT,‘quax~titate~~~e~~~ierN# particularum in quas aglc (Lit ffjle$E caUFz<br />

lUecllanic,r,) kd pro quantitate n~atcri~fiJOli~!~j & cujus altio in<br />

Jtsamenfi~s dikwtias undique extcndi turS decrefcendo i&per in<br />

duplicata ratione difiantiarum. Gravitas in Solem CO~lpOi~itU~’<br />

ex gravitatibus in Gngulas Solis particulas, St recedendo a Sole<br />

decrekit accurate in dupliczts rar~one difiantriarum ad uiquc or-.<br />

hem Saturni, uc ex quicte ApheliorIlm Flanetarum manifcRum eilt,<br />

& ad ucque ulrima Comeurum iiphelia, ii mode Aphelia illa<br />

quiekant. Rationem vero harum Gravitaris praprict~~tum ex<br />

Phccnomcnis nondum potui deducere, or: Hypotheks non fingo.<br />

Qicquid enim ex Phaznomenis non deducitur, HypotheJs vocanda<br />

eit j & Hypotheks feu Metaphyfics, ku Fhyfictn, ku Qualitatum<br />

occulrarum, feu Mechanicrt, in “PhPlofo/$z’d EX~E7imentnl~<br />

Bocum non habent. In hat Fhilo~ophia Propofitioncs deducuncur<br />

ex Pbxnomenis, & redduntur generales p&r Indufiionem. Sic<br />

impenetrabilitas9 mobilitas, SC imp,etus corporum 8~ iegcs motuum<br />

& gravitatis innotuerunt. Et fitrs cl1 quod Cravitas revera exifiat,<br />

& agat fecundurn leges a nobis expofitas, & ad corporuill<br />

c3z:lefii~1ti1 & .maris nofiri rnottis omnes fufficiat.<br />

Adjicere jam liceret nonnulla de §piritu quodam fubtiliili.mo corpora<br />

craffa pervadente, & in iifdem latente; cujus vi & a&ionibus<br />

particulz corporum ad miniwas difiantias k rnutuo attrahunt,<br />

& contiguz faQz colwrent; & corpora Ele#rica agunt ad difiantias<br />

majores, tam repellendo quam attrahcndo corpukula vilcina<br />

j & Lux emittitur, refleCEitur, refringiturs infk&itur , & ,corgora<br />

Cal&Citj & Senfitio omnis excitacur, & membra Ani-malium<br />

ad voluntatem moventur, vibrationibus fiilicet hujw Spiripus<br />

per folida nervorum cagillamenta ab externis fenfirum orgar~is<br />

ad cerebrum SC a cerebra in mufcu~Ios propagatis, Sed has<br />

paucis exponi non pof&nt; neque adefi Mkicns copia Experimentorurn,<br />

quibus Sieges aBionun3 hujus Spiritw accurate deter-<br />

Gnari & monfisari d-ebent.<br />

‘,


A.<br />

Quino&iorum prtecefio<br />

cau& hujus motus indicantar III,<br />

21<br />

quantitas motus eX caufis computatur III, 39<br />

den&s ad quamlibet altitudinem colligitur<br />

ex prop. 22 I Lib. II. quanta fit ad altitudincm<br />

nnius fccnidiametri Terrefiris ofien-<br />

&Rica vis quali caulk tribui poffit 11, 23<br />

gravitas cuni Aqua gravitate collata 47oj 3<br />

rcfiitcntia quanta GC, per Espcrinacuh Pendulorum<br />

colligitur 286, 28; pee ExPcriyenta<br />

corporum cadcntium & Thcoriam<br />

accur@s invcnitur 3 27, x3<br />

&aguli c~Qz~&iis non .fLmt cm3ncs ejnfilem generjs,<br />

J&J slii aliis infbitc minores p.,32<br />

Apfidum niol;us cspcndltur I, Se& p ,<br />

Area ‘~uas corpora in.gyr%s a&a, radiis ad contrllil1<br />

vjrium d&is, dcfcribunt, canhrnntur<br />

~11x12 temporibus dcfcriptianum. I, I, 2, 3,<br />

Author f, 17: 147~52: 172, 31: 483,34,<br />

c.<br />

CFli<br />

relifkntin de[lituWlul III, IO : 444, 20:<br />

4.7 I, 28 j & ~r~~~rercn.Fluiilo olaani COrpO-<br />

l-e0 328, 18<br />

Calorc virga ferrc~ compertn efi augcri longitndinc<br />

386, 4<br />

Calor sulk quant~rs fit: i,? diverfis a SpIc difbtiis<br />

qunntus apud Cometam anni IGO in Pcrihelio<br />

verfantcm 466, zz<br />

Centrum commune gravitaris corporum plwriam,<br />

ab atiionibus corporum inter fc, non<br />

mutat ftatum filum vcl motus vcl quietis<br />

P* a7<br />

Centrum commune gravitatis Tcrrz, Solis &<br />

Planctarum omnium quic~cecere III, I I j confirmatur<br />

ex Cor. 2. Prop. 14, Lib. 111.<br />

Ccntrum commune grav itatis Terra & Lunn:<br />

motu annuo percurrit Or&m magnum 3 7G, 6<br />

quibus intervallis difiata Terra & Luna 430,~~<br />

Ccntrum Virium quibus corpora revolventia in<br />

Orbibus rctinentur<br />

qtifili Arearam indicio invcnitur 38, i+<br />

qua ratione ex datis rcvolvenrium velocitatibus<br />

invenitur I, 7<br />

Circuli circumfercntia, qua .lcgc vis ccntiipetarr<br />

tendcntis ad pun&urn quodcunquc datum dercribi<br />

Pot& a corpore rcGolvcute I, 4, ,7, 8<br />

Comctae<br />

Genus font Planctawm , non Mcteororun~<br />

44.4924: 466, a r<br />

Luna fiiperiores fiint, 8: in rcgione Planetaruin<br />

verfkntur p. 43 g<br />

Difiantia eorum qua ratione per Obfervatim<br />

nes colligi Pot& quamproximc 439, 2 1<br />

plures obfirvati filnt: in hcmiljkzrio Solem<br />

verfirs, clunm in hemifPhsri0 oppofito; &<br />

unde hoc fiat 44+ r<br />

Splenden: lute solis a f.2 ICfieSil &ij.Lj.B+j LUX<br />

illn quanta cffct folet 4+!, 12.<br />

Cinguntur AcmofPhwis ingcntibus 442, x2:<br />

Q?$ ~Laa prqhs acccdunt ut plurilaauna<br />

nillorcs &ii cXi~irnnlltul* ~$77, 7<br />

Quo fine non comprcl’endlulltur Zodiacs<br />

(mwe Planetnrum) fed in omncs c~loruru<br />

qrioncs varic fcruntur 480,, 30<br />

Pofl’unt nliqunudo in Solem incidere & novtw<br />

illi nlimcncum ignis prxcberc 480,. 37<br />

‘Ulis eorum fuggcritur 47 3, I : 45 I, 7<br />

COIlI@-


avertunrur a Sole 488, 39<br />

maxirun: ftlnt & fulgentifimz fiatim pofi<br />

trarkum per viciniam Solis 467,8<br />

infignis earurn rnritas 470, 3 2<br />

origo ei nsturn earundem 442, 19: 467, 13<br />

(1~10 temporis fpatio a capite afcendunt 47 1) I<br />

COlll~t~<br />

Moventur in Se&tionibus Conicis umbilicos<br />

in centro Solis habentibws, & radiis ad Sokm<br />

d&is defcribunt areas temporibus proportionales.<br />

Et qnidcm in Ellipfibws rnoventur<br />

fi in Orbcm redeunt, hae tamen<br />

Parnbolis crunt maxime finitimz III, 40<br />

TrajcEtoria Parn!,olica ex datis tribws Obkrvationibus<br />

invenitur III,41 j Inventa corrigitur<br />

III, 42<br />

Locus in Parabola invenitur ad tempus dat’tllll<br />

445, 3CJ: I, 30<br />

Vclocitas cum vclocitate Planctarum confertul’<br />

44f> I7<br />

Cometa annorum 1664 & 1665<br />

Htljus motes obfirvatus expenditur, et cum<br />

Theoria accurate congrwere deprehenditur<br />

Com~ta~%orum 1680 & 1681<br />

Hujus moms obkrvatus cum Theoria accurare<br />

congruere invenitur p.4y5 & feqq.<br />

Videbatur in Ellipfi revolvi fpatio annorum<br />

plufqu”m qwingentorwm 464, 37<br />

TrajeBoria illius & Cauda lingulis in locis<br />

dclincantur p. 46~<br />

Cometa anni 1682<br />

Hujus motus accurate refpondet Theoria<br />

a.<br />

i. 479<br />

Comparuiffe virus eft anno I 607, iterwmquc rcditurus<br />

videtur period0 7s annorum 480~6<br />

Cometa anni 1682<br />

Hujus motws .ccwrate rcfpondet Theoriz<br />

I)* 478<br />

Curve: difiinguuntur in Geometrice rationaIes &<br />

Geometrice irrationales I on, 5<br />

Curvatura figurarwm qua rationc aeiiimanda fit<br />

235, 23 O: 398, 3f<br />

,Cycloidis fecu Epicycloidis<br />

retiificatio I, 4% 49 : 142, 1S<br />

Evolwta I, 50: 142, 22<br />

Cylindri nttrafiio ex particwlis trahcntibus compoliti<br />

quarum vires fwnt reciproce ut quadrata<br />

diflantiarum 198, L<br />

D.<br />

Dci Naturn p. 482, & 453<br />

‘Dckcnltis gravium in vacwo quantus fit, cx longitudinc<br />

Pendwli colligitur 377, I<br />

,Del’cen& vel Afccnhs reailinci fpatia dcfcripta,<br />

temporn defcriptionum & velocitates ac-<br />

quitke conteruntur, pofita cujuliuilqk gcneris<br />

vi centripeta I, Se&. 7<br />

Defcenft1s ?k Akenfus corporum in Mediis rcfifientibus<br />

II, 3,“8, g, 41~ 13~ 14<br />

E.<br />

Ellipfis<br />

qua lege vis contripetae tendentis ad ccntrum<br />

figutz defcribitwr a corpore revolvente<br />

I, IO, 64<br />

qua lege vis centripetz tendentis ad wmbilicum<br />

figurx defcribitur a corpore revelvente<br />

I, 11<br />

Fluidi definitio P. 260<br />

Fluidorwm den&as & comprefio quas kges habent,<br />

ofccnditur II, Se& c<br />

Fluidorum per foramkn in &k fatiwm efluentium<br />

determinatur motus II, 36<br />

Fumi in camino afcenfuus obitercxplicatur 4~2~4<br />

G.<br />

Graduwm in Meridian0 TerreRri menfira exhibctur,<br />

& quatn fit exigua inzqualitas o&nditur<br />

ex Thcoria III, 20<br />

Gravitas<br />

dive& eR generis a vi Magnetica 368, 27<br />

mutua efi inter Terram & ejus partes 22, 18<br />

ejus caufi non anignatur $83, 34<br />

datur in Planetas univerfos 365, I$J & pergendo<br />

a fuperficiebus Planetarum fur&m<br />

decrefcit in duplicata ratione difiantiarwm<br />

a centro III, 8, deorfwm dccrefkit in fimplici<br />

ratione quamproxime III, 7<br />

datur in corpora omnia, & proportion& eR<br />

quantitati materig in fingulis III, 7<br />

Gravitatem eire vim illam qua Luna retinetur<br />

in Orbc III, 4, computo accuratiori comprobatur<br />

430~25<br />

Gravitatem effe vim illam qua Planets primarii<br />

& Satellites Jovis & Saturni retinentur in<br />

Orbibus III, 5<br />

1-I.<br />

I-Iydrofiaticx: principia traduntur II, Se& 5<br />

Hyperbola<br />

qua legc vis centrifuge tendcntis a figure tentro<br />

defcribitwr a corpo1c revoivcnte 4,7,26<br />

.qwa lege vis centrifwgz tendentis ab umbilico<br />

figwrz defcribitwr a corpore revolvente j-r,6<br />

qua legc vis ccntripeta tcndcntis ad umbilicwm<br />

fi uraz defcribitwr a corpore rcvolvente T, I 2<br />

‘I[-Iypot 7 lefes cujufcunqwc generis rcjiciwntur, nb<br />

,hac Philofophia 484, 8.<br />

I. Iner-,


1.<br />

Illerti;e vis dcfinitur p. 2<br />

Juvis<br />

difinntia n Sole 361, x<br />

femidiamctcr npperens 3 71, 3<br />

fimidiamctcr Vcril 371, 14<br />

~ttmtiiva vis cjll~llta fit 370, 31<br />

p01ltlus corporunl in cjus fuupcrficic 37 I, 19<br />

ddras 3 7 1, 3!<br />

q~~antitas matcr1e 3 7 I, 27<br />

perlurbntiu 3 Saturn0 quantn fit 37f, 33<br />

~~iametroru~ll proportio compnto cxhibttur<br />

331,1-T<br />

convcrfia circum axc1n quo tcmporc abfolvi-<br />

I ,.<br />

~.OCUS &ii&w, & difiinguitur in nl9f0lutum &<br />

rclativum 6, 12<br />

Loca c~rporum in Se&mibus conicis inotorum<br />

invcniuntlW ad rempus afignatnm I,<br />

SC&, 6<br />

Luck<br />

propagatio non cfi infkmth3 2.07, f; n0:<br />

fit per a-gitationem Mcdii nlicuJus .&rhorc~<br />

342, 36<br />

velaclras in divcrfis Mcdiis divcrb I, 9r<br />

rcflexio qumhm cxplicntur 1, 96<br />

&m&i0 cxplicntur I, 94; 11011 fit in pun&a<br />

folum incidcnti~ 207, 29<br />

incnrvatio prapc carporun~ tcrminos Expcrimentis<br />

obfcrvata 207, 8<br />

LUKC<br />

carporis Ggura c!ompUto colli itur ll1, 38<br />

is& cdh pntcWkt, ct1r cant 8 cm kmpcr facicm<br />

in Tcrran~ obverrat 43 a, 9<br />

& lilwationes csplicantur III, I7<br />

dinnictcr nwdiocris appmcns 430, I z<br />

clian1cccr vcra 430, x7<br />

pondus corporum in ejus fupcrficic 430, 20<br />

dcnlitns $30, I$-<br />

vis sd Marc IYK~VC~U~ q”nntn fit TIT, 37;<br />

non fcntiri powIt in flxperimcnris pendularlm,<br />

vel jn Staticis aut tlydmfiaticis<br />

quibulkmquc 430, 3.<br />

teinpus pcriodicum 430, ?%<br />

tcmpus rcvulutionis i nod1c3o 398; 1<br />

maw mcdius cum 1 iurno motu Tcrrx: col-<br />

LUlw nms 8~ motu~ml inzqunlitates a car&<br />

fiyis dcrivantur IIT, 22: pdpr k fcc14.<br />

tardlus rcvolsitur Luna dilatato Orbe, ~II p<br />

rjheli0 Term; citius in nphcli~, contra&u<br />

Orb2 III, 22: 421, 6<br />

~aXh revolvitur, dilatat0 Orbe, in Ap0gzi<br />

SyzygiiS CLllll Sok; cities in Quadraturk<br />

ApogaC contra&o Orbe +22, I<br />

tnrdius rcvolvitur, dilataro orbe, in Syzygiis<br />

Nodi cum Sole; citius in Quadraruris Nodi,<br />

contra&o Orbe 422, 21<br />

tnrdius movctur in Quadraturis f& CURJ Sole,<br />

citius in Syzygiis j & radio ad Terram<br />

duRo dekribit: aream pro rempore minorem<br />

in priorc car& majorem in pokiorc<br />

III, 2~. : Inzqualitas harum Arearum cornpmtw<br />

lII, 26. Orh~ i&per habet magis<br />

curvum & longius a Terra recedit in<br />

priorc cafil, minus c1trv1~121 ha& Orbenl<br />

6~ propius ad Tcrram acccdit in poficriorc<br />

III, 22. Orbis hujus figura & proportio<br />

diamctrorum ejus computo colligirur III,<br />

28. Et fiibindc proponitur methodus invcnicndi<br />

dikmtiam Lunz a Terra ex motu<br />

ejus horario III, 27<br />

Apogeum tardius movctur in Aphelio Tcrrz.<br />

vclocius in Perihelia III, 22: 421, 21<br />

Apogrum ul9i tit in Solis Syzygiis, maxime<br />

progrcditur; in Quadraturk rcgreditur<br />

-<br />

IU,<br />

22: 422,37<br />

Ecccntricitas maxima cfi in Apoggi Syzygiis<br />

cum Sale, minima in Quadraturis III, 22:<br />

422~ 39<br />

Nodi tardius moventur in Aphelia Tcrrz, vblocius<br />

in Pcrihclio III, 22’: 4,2r. 21<br />

Nodi quiefcunt in Syzy$is i-iii; c& Sole, &<br />

vclocifimc rcgrediuntur in Quadmtnris<br />

III, 2%. Nodorum motus & inaqnalitates<br />

motuum computanrur cx Theoria Gravitatis<br />

Ill; 30, 3 I, 32, 33<br />

Inclinatio OrLis ad Eclipticam maxima eR in<br />

Syzygiis Nodorum cum Sole, minima in<br />

@adraturis I,66 Cor. JCJ. Inclinationis variationes<br />

computantur cx Thcoria Graviratis<br />

III, 34, 35<br />

Lunarium m0tuum Bquationcs ad ufus. ARronomicos<br />

p.421 ti fiqp<br />

&lotus mcdii Luna:<br />

&,quatio nnnua 421,.4<br />

fEquati0 fb-neilris prima 4.22, X<br />

&quatio km&is kcunda 422,21<br />

&quatio centri prima 423, 2!i: pi 101 Ik<br />

fcqq.<br />

~~qvntio centri fecunda 424, ry<br />

Vnriado pritia III, 29<br />

Varbio kcunda 42fa $<br />

Mob


~%‘iotus n\cdii Apogzi<br />

fEquati0 annua 421, 21<br />

fE+atio iemcfitris 4.22, 37<br />

Ecccutricitatis<br />

Quatio km&is 422, 37<br />

?~Iotiis medii NoJorum<br />

fik~uat10 annua 42 I, 21<br />

fEqu:ltio hneftris 111, 33<br />

Iuciillatiouis OrLilz ad Ecliplicam<br />

:Equalio Itmcltris 4,2r~, 22<br />

Eunarium motu11n1 ~l~corin, qua Methodo<br />

1+&n lir I‘c1’ Obkrvationcs 425, 33.<br />

M.<br />

fia-<br />

I\lagnetica vi:: 22, 13 : 271, 2f : 368, 29:<br />

MZi~~~iits a caulis iilis derivatur III, 24, 3G, 37<br />

Msrtis<br />

diltan~ia n Sole 361, I<br />

Aphziii motus 376, 33<br />

ii1atcr.i.r<br />

vis impreffa definitur p. 2<br />

c.~renfio, tlurities, impenetrabilitas, mobilitas,<br />

vis inertia, Eravitas, qua ratione innotefctmt<br />

3 ~7, 1 iJ: 484, 10<br />

divifibilitas nondum co&at f @, 18<br />

M&ria fubtilis CH’tt$ano?‘UflJ ax examen quoddam<br />

revocatur 292, I2<br />

Materia vel fibtilifima Gravitate non defiituitur<br />

368, I<br />

Mechanico, qufe dicuntur, Potentiae explicantur<br />

& demonfirantur p. 14 & 15 : p, 23-<br />

Mercurii<br />

difiantiaa Sole 3Gr, I.<br />

Aphelii motus 376, 33<br />

Mcthodus<br />

Rationtim primarnm & ultimerum I, Se&. I<br />

Tranfmutandi figuras in alias qua: fiint ejufdcm<br />

Ordinis Analytici I, Lem.22. pag.7~<br />

~ltixionum 11. Lcm. 2. P- 224<br />

Differentialis rI1, Lemk f & 6. pagg. 446<br />

p: 447<br />

ln~cn’iendi Curvarum omnium quadraturas<br />

pro&e veras 447, 8<br />

Scricrum convergcntium adhibetur ad iblutionem<br />

Problematum dif?iciliorum p. I 27 :<br />

128: 202: 235: 414<br />

Motus quantitas definitur p. I<br />

Motus abfolutas & relativus p. 6: 7: 8: 9 ab<br />

inviccm fecerni poffunt, exemplo demonfiratur<br />

p. IO<br />

‘Motus Legcs p. I2 EC feqq.<br />

Mottlum compoiitio si rcfolutio ‘p. 14<br />

&lotus corporum congredientitun poli: reflexioncm,<br />

qunli Eaperimento r&e colligi poffimt,<br />

oltcnditur 19, 21<br />

Moms corporum<br />

in Conicis feeRionibus ccccntricis I[, Se&, 3<br />

in Orbibus mobilihus I, Se&. 9<br />

in Superkiebus datis & Funependulorutn<br />

motus rcciprocus I, Se& IO<br />

Motus corporum viribus centripetis fc mutuo<br />

petentium I, Se&. 11<br />

Motus corporum Minimorum, que viribus &ntriFetis<br />

ad fiugulas Magni alicujus corporis<br />

parks tendentibus agitnntur I, Se&. 14<br />

Motus corporum quibus refifiitur<br />

in ratione velocitatis II, Se&. I<br />

in duplicata ratione velocitatis II, Se&. 2<br />

partim in ratione velocitatis, partim in cjul-<br />

dem ratione duplicata II, SC&. ” 2<br />

Motus<br />

corporum fola vi inlita progredieutium in<br />

Mediis refificntibus II, I, 2, f, 6, 7, I I,<br />

12: 302, I<br />

corporum re&a afcendentium vel defieuden-<br />

tium in Mediis rcfifientibus, agentc vi Gravitatis<br />

uniformi II, 3, 8, 9, 4.0, 13, 14<br />

corporum projcAorum in Mediis refiitentibus,<br />

agentc vi Gravitntis uniformi II, 4, I o<br />

corporum circumgyrantium in Mediis rcfifientibus<br />

11, Se%. 4<br />

corporum Funepcndulorum in Mediis refificntibus<br />

II, Se&t. 6<br />

Moms k refifientia Fluidorum II, Se&. 7<br />

Motus per Fluida propagatus II, Se&. 8<br />

Mows circularis ieu Vorticofus Fluidorum I&<br />

Se&. g<br />

Mundus orieinem non habet ex caufis Mechanicis<br />

p.432, 12.<br />

N.<br />

Navium co&uAioni Propofitio<br />

3w 4.<br />

0.<br />

non<br />

inutilis<br />

Opticarum ovalium inventio quam Carte& celaverat<br />

I, 97. Carreji:ni Probleniatis generalior<br />

foltitio I, 98<br />

Orbitaruni inventio<br />

quas corpora defcribunt, dc loco dato data<br />

cum velocitate, ficundum datum re&am<br />

CglTffj.; ubi vis centripefa en reciprocc ut<br />

quadraturn difbmtix: & vis illius quantitas<br />

abfoluta cognofcitur I, I7<br />

quas corpora defcrihunt ubi vircs centripet%<br />

funt rcciproce ut cubi difinntiarum 4~~ I 8 :<br />

x18,27: 12~, 25<br />

quas corpora viribus quibufcunqme centripetis<br />

agitata defcribunt I, SC& 8.


I N .D E dip R E .R v<br />

&lb<br />

in dive& Terra rrgionifus inve!liunrur &<br />

P. inter fc comgamtur III, z.<br />

Protlematis<br />

PaWh’ia, qua lege vis ccntripetaz tellden& ad K@hwi folutio per Trochoidcm & per<br />

umbilicum figur;e, dehibitur a corpore rcvol- Approximationes I, 3 I<br />

ventc I, 13 Veterm de quatuor his, a ~q~po memorati,<br />

Peadulorum affettiones cxplicanrur 1, $0, pI, a Cautf&o par cnlculum Analyticum tcntati,<br />

52, 53: II, Sea. 6. cornpolitio Geometrica 70, I g<br />

Pet%dUlorum iibchronorum lon~itodines diverfz ProjcCtilia, il’pofita Medii rcliltcatia, moveri ilr<br />

in diverfis horum Latitudlnihs inter {e Parabola col@tur 47, 23 : zoe, 23 : 23G, 29<br />

co~1feruntur., turn per Obfcrvatio~~s, turn per Projcc’Nium motus in Mediis reliiIcntihs II,<br />

‘Pheoriam Gravitatis 1x1, 20 &,I0<br />

Rhik&oplmndi Regul~ p. 357 Pulhnn Acris, quibus Soni propagantur, detcr-<br />

Planeta minantur intervalln feu latitudines II, 50: 344,<br />

r1otl dcFcrontur a Vorricibus corporcis 3r2, 16. Hnc intervalla in apertnrum Fihhtm<br />

.37: 3j-4, 2g: @I,21 his zquari duplis longitudinibus Fifhlnrum<br />

Priinarii vcrofimile CR 344, 2G<br />

Solem cingunt 360, 7<br />

Inoventur in Elliplibus umbilicum habeuti.<br />

CL<br />

bus in centro Solis III, 13<br />

radiis ad Solem du&is dcfcribuut areas tern- Quadrntura generalis Ovalium dari non pot&<br />

poribus proportionah 361, rf : III, I 3 per hitos termiuos I, Lem, 28. p. g8<br />

tcmporibus pcriod,icis rcvolvuntur que ht C$alitates corporum qua ratione innotehnt &<br />

in fcfquiplicata rntione difiantiarum a admittuutor 3f7* 16<br />

Sole 360, 17 : III, 13 & I,, I$ Qaics vera & relativa p. 6, y1 S, 9.<br />

rctinentur in Orl.+tus his a vi Gravitatia<br />

qu2.2 rcfpicit Solcm, & elk reciproce ilt R.<br />

quadraturn diitantis nb ipfiw ccntro<br />

,IIX, 2, 5 RefiRentiz qwntitas<br />

Sccundarii in .Mediis non continuis II, 3~<br />

k2ovcntur in EllipGbus umbilicum balxxti- in, Mcdiis continuis II, 3 8<br />

bus in ccntro IYimwiorum III, 22 in Me&is cujuhtnque generis 303, 32<br />

racjiis ad Primaries ,.(iuas duQis defcr$~mt Refificntiarum Theoris conihnatur<br />

areas temporibus proportionales 3 p9, 3, per Experimenta Peudulorum II, 30~3 I, Sch.<br />

ZLZ: 361, 27: III, 2%<br />

Gen. p. 284<br />

~emporihis periodicis revohultur qu” hit per Experimenta corporum CadentiWl 11, +h<br />

in fiijuiplicata hone difiantiarum a Sch, p. 3 rg<br />

Primariis his 3 59, 3, za : SKI, 22 ik I, 11 Refieutia Mcdiomm<br />

r&incuttw in Orbihs his a vi Gravitatis CR’ tit cprundem detlfitas, c~teris paribus<br />

quz rcfpicit Primnrios, & efi reciproce 290,2.9: 291,3y: 11,33,35-, 38: 327, '4<br />

ut’ quadrntum diRantire ah eorum cewris eR in duplicata rationc vclocitatis corporum<br />

m I, 3%4, ,P quibus refifkitiir, cWzris paribus 217, 24 :<br />

Planetarum 2849 33 j 11, 33*35138: 3% 23<br />

difksntix 3 SoIc 36X, I cR in duplicata rationc dinmctri corporum<br />

Orbium A$wlin & Nodi prope quichint Sphwicorum quibus refifiitur, cztcris pa-<br />

III, I$ ribh 288, 4: zgp, 11:’ II, 33, 3~~ 38:<br />

Qrbes determinantw III, z 5, 16 Sch. p. 3 I9<br />

10~3 in Ohibus invcniuntur x, 3 I aon iyinllitilr ab a&ionc Fluidi in pwtcs po-<br />

&dim cnlori quizm a Sole rccipiiiuh ac- fticas corporis inoti 3 12, 23<br />

conm~oclntur 372, 7 Rcfifktitia Pluidorum dttplcx cfi; oriturquc vel<br />

converfiones diurw fiint tfquabilcs 1x1, * 7 al2 1nertin match Auidz, vcl nb Elatiicitntc,<br />

axes font minorcs diamctris q~;e ad eofdelu Tcuacitatc & FriQione partium cjus 3 13, I.<br />

axes normaliter ducuntUr 111, J 8 ,Relificntia ~LI’C htitur iu I;‘luidis i’erc tota<br />

Fondcra corporum efi prioris gcneris 326, 32, 8: mintti non pojn<br />

TC~IYIIII ~1 ~&rn vcl Plnnctnm qtlemvis~ tcfi per fi&ilitntonl ywti~~xn Phi&, ,runocnte<br />

L paribus difiant$s ,311 cortm7 ccntris~. iimt ut deillitatc 325, 7<br />

gUantitates mater& ill corpnribiis II& 6 Refifie~~ti? ;Globi, ad refificntiam Cyhdri pro-<br />

IIC)~I pdctlt 3b c0rm Eormis & texturis portio,.;Lydiis, non co,ntinuis II, 34<br />

\ ’ * It&h-<br />

‘pa67.3.f


~cfif\entin qunm yntitur a Fluid0 fruitum CO-<br />

IIIC~IIII, qu3 ratione fiat minima 299, 3’1<br />

Rclillwtin: minima Solidum 300, 15.<br />

S.<br />

SJtclliris<br />

~uvidis estimi elongntio maxima holioccntricn<br />

n centro Jovis 370, 3~<br />

.FI~~grni,wi elo~igatio maxima hcliocentricn a<br />

centro Saturni 37 I, f<br />

Snlcllitum<br />

lovialium tcmpora pcriodica Sr difiantk a<br />

d centro Jovis- 1~9,~’ 2<br />

Sattrrniorum t&pora periodica & difiantiz a<br />

ccntro Saturni 360, 1<br />

Joviaiiuni & Snturniorum inzqualcs motus<br />

a motibus Lunz derivari pofi‘c ofknditur<br />

111, 23<br />

Saturni<br />

difiantia a Sole 3Gr, 1<br />

femidiameter appni-ens 37 I, 9<br />

fimidiameter vcra 3 7 I, 14<br />

vis attra&iva quanta fit 370, 33<br />

p011dus corporum in cjus fuperficie 371,19<br />

denlitas 37r, 37<br />

quantitas matcria: 371, 27<br />

perturbatio a Jove quanta fit 375, 16<br />

diameter apparcns Annuli quo cingitur 37 I, 8<br />

SeEtiones Conicz, qua lege vis centrlpetae tendentis<br />

ad pun&urn quodcunque datum, defcribuntur<br />

a corporibus revolventibus &20<br />

Sc&ionum Conicarum defcriptio Geometrica<br />

ubi dantur Umbilici I, Se&, 4<br />

ubi non dantur Umbilici I, Se&. y. ubi dantur<br />

Centra vel Afymptoti 87, 9<br />

Sefquiplicnta ratio definitur 31, 40<br />

Sol<br />

circum Planetarum omnium commune gravi-<br />

tatis centrum movctur 111, 12<br />

femidiamcter ejus mediocris apparens 37 I, 12<br />

iemidiameter iera 37 I, 14<br />

parallaxis ejus horizontalis 3 70, 33<br />

uarallaxis menfirua 276, 4<br />

ks ejus attra&iva &&;a ‘fit 370, 3 3<br />

pondus corporum in ejus iiipcrficic 37 I, I9<br />

den&as ejus 371, 37<br />

qua&as mnterke 3 7 r, 2 7<br />

vis ejus ad perturbandos motus Luna: 363,<br />

15: III,25<br />

vis ad Mare movendum III, 36<br />

Sonorum<br />

nntura cxplicatur 11,43,47,48,49, $0<br />

propagatlo divergit a re&o tramite 332, g,<br />

fit per agitationem Aeris 343, I<br />

velocitas computo colligitur 343,8, paiilulum<br />

major effe debct Bfiivo quam Hyberno<br />

ternpore, per Thcoriam 344, I I<br />

ceffatio fir fiatim ubi ceffat motns corporis<br />

augmentatio per tpbos ficnterophonicos<br />

3+4,32<br />

Spatinm<br />

nbfolutum & rclntivum p. 6,~<br />

non tit aqualiter plenum 368, 16<br />

Sphrrroidis nttra&io, cujus particularum vires<br />

hnt rcciprocc ut quadrata diitantiarun~<br />

198, 21<br />

Spiralis qua: i&at radios fuos omnes in angulo<br />

data, qua lege vis centripetz tendentis ad<br />

centrum Spiralis defcribi potefi a corpore<br />

revolvente, ofienditur I, 9: II, 15, 16<br />

Spiricum quendam corpora pervadentem & in<br />

corporibus latentem, ad plurima narum phznomena<br />

folvenda, requiri fuggeritur 484, I 7<br />

St&rum fixarum<br />

quies demonfiratur 376, r8<br />

radistio & fcintillatio<br />

quibus cnufis rcfercnd;E<br />

tint 467, 38<br />

Stelle Now unde oriri poffint 48 I, 5<br />

Subfiantiazrerum omnium occulta: fimt 483,23<br />

T.<br />

Tempus abfolutum & relativum p. 5,7<br />

Temporis &quatio Aftronomica per Horologium<br />

ofcillatorium & Eclipfes Satellitum Jovis<br />

comprobatur 7, IF<br />

Tempora periodica corporum revolventium in<br />

Ellipiibus, ubi vires centripetz ad umbilicum<br />

tendunt I, I$<br />

Terra<br />

dimenfio per Picnvttm 3 78, I I, per Caflgtim<br />

3y8,2r, per No~~oorluna 378, 28<br />

figura invenitur, & propordo diamctrorum,<br />

& menfura grnduum in Mcridiano III,<br />

19, 20 -<br />

altitudinis ad AZquatorcm filpra altitudinem ad<br />

Poles qunntus iit exceffus 38 x,7 : 387, I<br />

fimi$inmcter maxima, minh & mcdiocris<br />

387, IO<br />

globus denlior elz quam ii totus cx Aqua con-<br />

hrCt 372, 31<br />

globus denlior eR ad centrum<br />

quam ad filper-<br />

ficiem 386, I:<br />

molcm indics augeri verofimile tit 47 3, I 8 :<br />

@I, 13<br />

axis nutatio 11X, 21<br />

motus annuus in Orbc magna demonfiratur<br />

III, 72, ‘3 : 478, 26<br />

Eccentricitas quanta fit 42 I, I 5<br />

Aphclii motus quantus fit 376, 33.<br />

V.<br />

Vacuum datur, vel fpatia omnia (G dicantus<br />

effe plena) non funt azqaalirer plena 328,n<br />

36% as<br />

8 z


Cor. 2<br />

Velocitates corporum in SeLkionibus conicis motornm,<br />

ubi vires ccntripek ad umbilicum<br />

tendunt I,. 16<br />

Veneris<br />

djfiantia a Sole 361, I<br />

tempus periodicum 370, 23<br />

Aphelii moms 376, 33.<br />

Virillm compoiitio & relolutio p. 14<br />

Yircs attraLtive corporunl<br />

fpI~~riCOlWtl1 cx particulis qnacunque lege<br />

trabentibus compofitorum 9 expcnduntur<br />

I, SC&. 12<br />

non fpkericorun~ ex pmticnlis qnacunque<br />

lege trahentibus compofitorum, espenduntur<br />

I, Se&. 13<br />

vjs ccntrifuga coryorum in Bquatorc Terra:<br />

quma fit 3791 2.2<br />

Vis centripcta definltur p. 2<br />

quan&as ejus abfoluta dcfi$tur p. 4<br />

quatltitas accelcratrix ~CfillltUl* p. 4<br />

qua&as matrix dcfillltW p. +<br />

yroportio cjas ad vim quamhket notam, qua<br />

rarionc colligenda fit, ofkndltur 40, r<br />

,vi&m CcntripetalXUI inventio, ubi corpus in<br />

{patio non rcfificntel circa ccntfwm imnlobile,<br />

in Orbe qu0CuII~~UC rCVohtur I, 6: I,<br />

Se&* 2 82 3<br />

Viribus ccnEripctis datis ad quodcuuque pun-<br />

&m fcn~cmibus, quibus. Figum qwvis a<br />

.- .’<br />

corporc ~.cr~olve~~te dehibi potefi ; dnntur<br />

vires ccntripetz ad aliud quodvis pun&m~<br />

tcndenrcs, qhibus eadem Figurn codcm tern--<br />

.p~re periodic0 defcribi pot& 44, 3<br />

Vu&us ccntripetis datis quibus Figura qurvis<br />

defcribitur a coryore revo1ventc.c; dantar vires<br />

quibus Figura nova deli-ribi potclt, li Ordinat32<br />

augeantur vel minuantur in ratione quacunquc<br />

data, vel angulus Ordinationis utcunque<br />

mutetur, nxmente tcmporc periodic0<br />

47, 28<br />

Viribus centripetis in dnplicatn &one difiantiarum<br />

decrekencibus, quznam k’iguw delcribi<br />

poffunt, oitenditur 5 3, 1 : I 50, 8<br />

Vi centripcta<br />

quze fit reciprocc at cubs ordinstirn applica.<br />

Ke tendcntis ad centrum virium maximc<br />

l0ngi11quum , corpus movebitur in dara<br />

quavis coni fXtionc 4~, 1<br />

qw fit ut cubus ordinatim applicata ten&n-.<br />

fis ad centrum virium maxime longincl uum,<br />

corpus movcbitur in Hyperbola 202, 7.6<br />

Umbra Terre&is in Eclipfibus Lunz auger& ck<br />

proptcr Atmof$harz rcfra6Conem 4,2~, 27.<br />

Umbra: Terre&is diametri non ftmt qualesj<br />

quanta fit differentia oRenditur 387, 8<br />

in aqua2 fiagnantis fiperficie propavelocitas,<br />

invenitur II, 46<br />

Voiticum natura 6% confiitutio ad examcn rcvoratur<br />

II, Se&. 9: 48 I, 2 x<br />

UC. Hujus vocuIae fignificatio Mathcmatica dc{<br />

,finitur 30, 19. 1<br />

. . L


ACT. 3, h. I 4 igc, C$o minur wit. ejus gravitas pro quantitatc mntdx vcl major kc.<br />

I’. ;> I. S [qy, ut cx veriorc ternpore nlcoiixent motus ,&c. P.If, l. 115 Iege, ham PH<br />

i!l plXl& kc. r. 17, 1. 20 loge, ccntri corporis tertii kc. p. 41, 1.3 zcge, runt reciyrocc ut<br />

vclocitatcs cwporis in puu&is P kg; kc. P. 44, i. 23 hge, re&nngdo &&LZX % It N+ ZN &c.<br />

P. 47. 1. ~xw!z. LL~F, iu Abfccifi pofitum rcndcntes a binis quibufvis figurarum lock, ad qua terminantw<br />

Ordinata correfpondcntibus Abfci~l~rum punLtis infiftentes, augentur vel &c. I’.549 I.4<br />

ZC~C, ut arca ~T%SP, qus dnto tcmpore dehibitur, du&a in &c. P. 51~ 1.25 Zege, Nimirum<br />

ii calit corporis kc. P,Gl, k12 Icgc, ita ut fit GA ad AS & Gw ad aS ut et% KK<br />

ad B S, .& ax kc. 1.1’5 Iegc, & cum iit GA ad AS ut Gti ad a~, erit divifim Ga ---GA<br />

SixI ~a ad ns -AS Seu SH in eadcm kc. P. S7, 1. 7 Zcge, per Protl. XIV. kc.<br />

P. 89 S: P. go iv j&w.3 jnngatw FB. P. 92 in figura junganrrrr FG & H 1. 2. ‘363<br />

Z. 2 Icge, perimetrunl BP tic, B. 16l, 1. S lege, motus uterqw wit UC tempus periodicurn<br />

corporis kc. P. 233, 1. I&. lege, $yzQRo3 +-kc. P. 244; 1.22 Iege,<br />

ZU@-273<br />

VG.<br />

n-2<br />

Y. 3 17, 1. pemlt. lefe, velocitntem i/lam mnximam H, &c. P. 367, I. s4 lege, eccentricitas<br />

foret &c. P. 379, 1. 13 2-c 23 Iege, vim centrihgam corporum &c. P. 4lf, 1. I I lege$<br />

f-kzc eR zquatio fimeftris motus Nodorum. ,R. 41J, 1. a$ lege, alteri ,fkneRri, alteri sutem<br />

menitrw j &c.<br />

J

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