1938 Proposal

The National Cash Register Company, Figuring Book for Engineers and Draftsmen, Book 5810 , No. 1; J R Desch, Research Department, May 31, 1938, p. 16, Sept. 15, 1938

A scheme to use gas filled thyratron tubes as impulse counters in a system of addition and multiplication has been set up to determine the operating conditions for the thyratron 884 and 885 tubes available at this time. The original scheme was intended for cosmic ray counting and was set forth in “Electron Tubes in Industry.” A sketch attched to this page shows my first conception of how this chain of tubes could be used to count and transfer a pulse to a second higher order counter. Of course ten tubes and a transfer tube are necessary in adding one column of digits and as many sets of counter tubes are necessary as there are figures in the sum required. For a sum in 6 figures, then six chains of counters are necessary. Accordingly a set up has been made arranging 5 tubes in order in the circuit shown and impulses from a commutator sent to the system. With impulses sent at a relatively slow speed, visual observation of the successive tripping of the tubes is possible. At high speeds the eye cannot follow the successive tripping of the tubes, all appear ignited and firing.