chess-The Oxford Companion to Chess - First Edition by David Hooper & Kenneth Whyld

68 CLEARANCE
live world chanpionship clenrs, quarter- and
seni-final respectively. In tournanenh ar New
York us$r made a clean score in r89l (+13).
Capablanca in 1913 (+13 including one d.fauli)l
but Fischer naiie the most remarkable achielenent
ol thn kind (+11) in the US chanpionship
1963, a toumamcnl ot abour cateeory 10.
CLDARANCE, or line clearance, a problem ma.-
cuvre in which a pie€ is moved alonB a line to
nate way for another piece ol the same colour to
be moved along thc same line. For two ofthe ways
in which lhis can be donc see ANNrsrL^rroN. add
B{srol CLFARANC!. (c.npare LrN. vacAroN.)
CLEMENZ OPENING,698, naned after tne
Estonian player Hermann Clenenz 0816 1908).
CLOCK, or .le$ clock, a device lor recordine
sepa.ately th€ timc takcn by cach player lbr
his noves. (For an earlier timinC dc,i.e scc
SANDGLA$.) When docks be8an to be ukd the
ruleswcre somelines based on $e manmum rime
for each move, and a singlc clock sutlied. Oilen
shen two cloclc were used one vas a$andardlimc
piccc the othei a stopwa tch , and the time taken b,
the player with tne ordinary clock was calc ated
by subtracting the stopwat.h reading. For rhe
ANDERSSEN sErNrz natch ol 1866 the rimc lor
each mov. was recorded and the lotal time
c.lculared by addilion. Ciadually ir be.ame rbe
cuslon lo use rwo pendulum clocks, one for each
player. While one playeis clock was iicking thc
oiher clo.k was lain on its side.
Prompled by a disossion with BLACGUNE,
Thoh.s Bnght Wihon (1843 1915). se.rctary oI
tie Ma..hester che\scluh devised i irhnd wiih,
hovable beam. like a sc.saw, to hold two
pendulun clocks. This was used for thc intema
tional tournaoenl, London 1883. TIE rippi.g ol
the beam caused one clock 10 stop phile lhe other,
in an upnghl position, was goingj 'which saves
trouble and cannol Nell go wro.g. So much.annot
be said ol the minor toum,menr ckicks vhi.h
unless care was taken, had alrick ofgoingoneven
when turned o. their backs. A cotrnrer rotled up
the numberoitines the be.n had been iipped and
abcll rangwhen the requirednunberof moveshad
beenmade. In l68TFaltoriniolBradfordbrought
out a sinilar stand but withont ihe counr* a.d
beil. This cheap delice sold wel for sone rime but
had two majo. deleds: both clocks could not be
sbPped al thesanetime and unles the beamsas
noled at $e nght speed tbe upnght clock vould
not start. The fi6t ches patent laken out in the
United Kingdom was in 188,1i it was tor a clock
designed by Amandus SchieMaterj a watch and
clock maker lron Uverpool. He made improvements
in timepieces, applicable for indicaling the
time spcnt by cach playerwhen playing g.nes, and
for other puryoses . . it n desig.cd chielty tor
recording tbe movenents ol a gane ol chess . . .
though it @uld easily be adapted . . . lor orher
usefDl purposes- such as . . . tralellers passine
from placetoplacc. the time ollhep.rticularplace
could be nored on lhe secondary dial- wnhout
havingtoaller. . . tbeprinarydial.'rhelargcdial
showcd the tolal tine while snall dlals on eithet
side showed ca.h playcls individual tine. A large
ineer on lhe central dial showed lhc total number
ofnoles played.nd a snal nnger pointed to rhe
sid€ shosc clock sd ticking. This lirst true chess
clock was well liked. but had a short lile.
Ofa clock used ar Leipzig 1894 socER wrotc: 'A
A ches clock of.hc 1390s:
rhc a.on shaped leidurutrE
werc noppcd ed $aned bt,
ltum one side to the othcr