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– The Tate-Layton machine was largely based on the work of Thomas de Colmar and other 19th century arithmometers. – Charles and Edwin Layton, founders of C. & E. Layton, were originally publishers.
Tate-Layton’s machines are generally considered to be the heaviest duty and best made of all of the late 19th century arithmometers. They were primarily manufactured for use by the insurance industry.
The plate that covered the drums and top of the machine had slits in it to allow these and other parts to move. The edges of the slits next to digit levers were numbered from 0 to 9 to indicate the digit entered.
Like previous arithmometers, the machine was popular in the insurance industry for performing complex calculations.