Calcul Mecanique -- Machine a calculer fondee sur l'emploi de la numeration binaire (Valtat, pp. 1745-1748) WITH Sur l'emploi de la numeration binaire dans les machines a calculer et les instruments nomomecaniques (Couffignal, 1970-1972) in Comptes Rendus 202, 1936, [VALTAT’S IMPORTANT DESCRIPTION OF HIS PATENTED CALCULATING MACHINE ALSO: COUFFIGNAL ON ELECTRICAL CALCULATORS]

Paris: Gauthier-Villars, 1936. 1st Edition. Full volume. FIRST EDITION OF VALTAT’S DESCRIPTION OF HIS PATENTED CALCULATING MACHINE FOUNDED ON THE CONVERSION OF DECIMAL INPUT INTO BINARY INPUT PRIOR TO CALCULATION. Valtat here notes “that binary digits could be represented either mechanically or electrically. He also stated that in an electric circuit the switch "on" would equal 1 and the switch "off" would equal 0” (Jeremy Norman, History of Science). As noted below, some instead credit Louis Couffignal who in 1936 and in this same volume, wrote of employing binary notation in a calculating machine. Couffignal "argues the utility of representing numbers by binary notation in computers and discusses the design of electrical calculators" (Aiken, Proposed Automatic Calculating Machines, 10).

A Frenchman, Raymond Valtat (1898-1986) patented his calculator in 1932, but this 1936 paper is his first written account of his invention. In this paper, Valtat finally explains his thought and methodology, strongly advocating for the usage of the binary system in calculating apparatus over that of the decimal system.

The scholarship on the invention of the first binary-based calculating machine is confusing. The discovery is sometimes credited to Claude Shannon’s master’s thesis published in 1938 but written in 1937. Some credit Konrad Zuse who working in Germany, applied for a patent on a binary calculating machine in 1936. Others credit Louis Couffignal who in 1936 also wrote of employing binary notation in a calculating machine. Valtat, however, “may have been the first to propose a binary-based calculating machine” – this because though he did not publish until 1936, he applied for his patent in 1932, thus predating both Zuse and Shannon (Norman; Ptak). Randell 1982a, 519-20. Origins of Cyberspace 397. Item #680

CONDITION & DETAILS: Complete volume. Ex-libris stamp on the rear of the first page; slight ghosting at the spine where a spine level has been removed. Illustrated throughout, including the Pouillet paper. 4to (11 x 8 inches; 275 x 200mm). Continuously paginated: pp. 1225-2331. Full blue cloth binding, gilt-lettered at the spine; ghosting from the removal of a label at the spine; stamp on the rear of the title page.

Price: $250.00