First Appearance of the Conversion of Decimal=>Binary Input and a Computing Classic (1936)

VALTAT, Raymond. "Calcul mecanique.-Machine a calculer fondee sur l'emploi de la numeration binaire." In Comptes rendus 202 (1936): 1745-48 in the weekly issue of pp (725)-824, removed from a larger bound volume.  Followed by:  Maurice d'Ocagne, "Observations relatives a la note de M. Raymond Valtat", pp 1747-1748, same issue.  AND WITH: M. Paulino Castellas Vidal, "Sur une machine a resoudre les systemes d'equations lineaires", this too presented by d'Ocagne, pp 1748-1751.  GOOD copy, only; this has an old vertical crease running vertically through the issue.  On teh positive side, this issue has its original front wrapper, though it is somewhat tatty around the edges.  Provenance: U.S. Weather Bureau.  $300

Raymond Valtat (1898-1986) filed a patent in 1932¹ for a mechanical calculator founded on the conversion of decimal input into binary prior to calculation², publishing his results on his calculator for the first time in this issue of the  Comptes Rendus in 1936. This came before those contributions at very nearly the same time as Louis Couffignal (who in the 1936 wrote on “the use of the binary notation in the calculating machine” and who "filed a patent in 1936 for a mechanical calculator founded on the conversion of decimal input into binary prior to calculation"--history-computer dot com). There is also John Atanatsoff who in 1939 built the first prototype binary computer,  William Phillips, Alan Turing (working in 1936 on an electromechanical binary multiplier), and Konrad Zuse in Germany. Valtat's work also preceded that of George Stibitz's binary adder of 1938, and also that of Claude Shannon (in his thesis published n the AIEE Transactions in 1938).  

Valtat's paper was presented to the Academy by Maurice d'Ocagne, inventor of the nomogram, mechanical engineer and mathematician, who was also mentor and teacher and calculator-nurturer of Couffingal, and a very busy man.

Notes:

1. Midhat J. Gazalé, Number: From Ahmes to Cantor p 54

2. George Dalakov, History of Computers website, http://history-computer.com/Babbage/LouisCoufignal.html