Les Intégraphes. La Courbe Intégrale et ses Applications. [Bound together with C. Bohn: Über Linsenzusammenstellungen und Ihren Ersatz].

Paris, Gauthier-Villars, 1886. Royal8vo. In contemporary half cloth with paper label pasted on to top of spine. Occassional brownspots throughout. With 94 figures in the text. X, 156 pp.; (4), 88 pp. 20, 16, 15, 18, (31) advertising

First edition of Abakanowicz's famous integraph. It was invented independently about 1880 by the British physicist Sir Charles Vernon Boys and by Bruno Abakanowicz, however, the later being referred to as inventor (Goldstein, L'Europe mathématique: histoires, mythes, identities). "The developments in the integraph design made by Abdank-Abakanowicz in France in the 1870s have been acknowledged as amongst the most noteworthy" (Small, The Electronic Analogue Computer, P. 59).

"The integraph is an elaboration and extension of the planimeter, an earlier, simpler instrument used to measure area. It is a mechanical instrument capable of deriving the integral curve corresponding to a given curve. Hence, it is able to solve elementary differential equations graphically. However, it was not until 1878 that he succeeded in developing a practical model. "
This volume is a description of the basic Abakanowicz instrument and a few of its later modifications. Abdank-Abakanowicz's instrument was able to produce solutions for only simpler differential equations, i.e., the commonly entountered class having the form dy/dx = F(x). An instrumental solution requires that as a first step a graph of the function F be drawn. Next, a pointer on the instrument is used to follow (trace) this graph. The value of the integral may then be read from the instrumentdials. This Abakanowicz approach was widely adopted in the early twentieth century, and the instrument was produced, and later improved, by such well-known instrument makers as Coradi in Zurich" (The Erwin Tomash Library, Vol. 1, p. 2.).

Bound with Abakanowicz's Integraph is:
Répertoire Alphabétique des Procédés et Recettes publiés par Le Monde de la Science et de l'Industrie pendant les Années 1880 à 1886. Lausanne, Jaunin, 1887. 15 pp.
Du régime de l'invention. Examen des améliorations proposées à la législation relative aux inventions à propos du nouveau projet de loi sur les brevets. Paris, A. Durand, 1862. 160 pp.

Erwin Tomash Library A1.

Order-nr.: 49270

DKK 6.500,00