CHASLES, MICHEL.

Histoire de l'arithmétique - Règles de l'Abacus.

(Paris, Bachelier), 1843. 4to. No wrappers. In: "Comptes Rendus Hebdomadaires des Séances de L'Academie des Sciences", Tome XVI, Pp. 218-46. (Entire issue offered: Pp. 215-80 ).

First appearance of Chasles' famous paper in which he via the tenth century wrintings on the abacus by the monk Gerbert (later Pope Sylvester II) argued for a Pythagorean rather than a Hindu origin for our numeral system.
"Gerbert's abacus was not a standard table abacus, but had columns in which special counters were placed. It is thought that Gerbert, disguised as an Arab, made his way into Spain and learned of the Hindu-Arabic numerals there. The Gerbert abacus was not convenient to use and was soon abandoned." (Erwin Tomash Library C70).

"Chasles wrote two historical works elaborating points in the Aperçu historique (notes 12 and 3 respectively) which had given rise to controversy. The histoire d'arithmétique (1843) argued for a Pythagorean rather than a Hindu origin for our numeral system. Chasles based his claim on the description of a certain type of abacus, which he found in the writings of Boethius and Gerbert. The second work was a reconstruction of the lost book of Prisms of Euclid (1860). Chasles felt that the porisms were essentially the equations of curves and that many of the results utilized the concept of the cross ratio. Neither of these works is accepted by contemporary scholars." (DSB).

(Erwin Tomash Library C70)

Order-nr.: 50603