P. HISTORY OF ' AATHEMATICAL - School of Mathematics

EQUALITY 303
the most influential mathematicians of the seventeenth century. It
worked its way into more elementary textbooks. Jean Prest,etl
adopted it in his Nouveaux l?l~mens, published at Paris in 1689. This
fact is the more remarkable, as in 1675 he2 had used the sign =. It
seems to indicate that soon after 1675 the sign w was gaining over =
in France. Ozanam used in his Dictionaire mathematique (Amster-
dam, 1691), though in other books of about the same period he used
-, as we' see later. The Cartesian sign occurs in a French text by
Bernard lam^.^
In 1659 Descartes' equality symbol invaded England, appearing
in the Latin passages of Samuel Foster's Miscellanies. Many of the
Latin passages in that volume are given also in English translation.
In the English version the sign = is used. Another London publication
employing Descartes' sign of equality was the Latin translation
of the algebra of the Swiss Johann Alexander.' Michael Rolle uses w
in his Trait6 d7alg8bre of 1690, but changes to = in 1709.6 In Holland,
Descartes' equality sign was adopted in 1660 by Kinckhvysen,B
in 1694 by De Graaf,? except in writing proportions, when he uses =.
Bernard Nieuwentiit uses Descartes' symbol in his Considerationes of
1694 and 1696, but preferred = in his Analysis infinitmum of 1695.
De la Hires in 1701 used the Descartian character, as did also Jacob
Bernoulli in his Ars Conjectandi (Basel, 1713). Descartes' sign of
equality was widely used in France and Holland during the latter part
of the seventeenth and the early part of the eighteenth centuries, but
it never attained a substantial foothold in other countries.
265. Variations in the form of Descartes' symbol.-Certain variations
of Descartes' symbol of equality, which appeared in a few texts,
are probably due to the particular kind of symbols available or improvisable
in certain printing establishments. Thus Johaan Cam-
1 Jean Prestet, Nouveauz ~1hen-s &s mathdmaliques, Vol. I (Paris, 1689),
p. 261.
J. P. [restet] &has des mathdmaiiques (Paris, 1675), p. 10.
a Bernard Lamy, Ehens des malhematiques (3d ed.; Amsterdam, 1692), p. 93.
Synopsis Algebraica, Opua poslhumum Johnnis Alezandri, Bedis-Heluelii.
In usum scholae mdhematieae apud Hospilium-Chrisli Londinense (Londini, 1693),
p. 2.
6 Mem. & I'acadhie royale &s sciences, mn6e 1709 (Paris), p. 321.
'Gerard Kinckhvysen, De Grondl dm MeeGKonsl (Te Haerlem, 1660), p. 4.
7 Abraham de Graaf, De Geheele Mathesis of Wiskunsl (Amsterdam, 1694),
p. 45.
De la Hire, Noweaw dL4mem des sectha coniques (Paris, 1701), p. 184.