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Felt & Tarrant Manufacturing Company, Chicago USA.

The Felt and Tarrant Manufacturing Company was founded to manufacture the Comptometer, invented by Dorr Eugene Felt and patented in 1887. This machine was the first truly practical and commercially successful adding machine, with the first serious manufacture and sales occuring in 1888.

The Comptometer was a very successful adding machine. There was steady development and these machines were produced into the early 1970s. Felt and Tarrant also diversified into leisure goods and developed the Electrowriter which transmitted what was written on a special pad.

In 1957 the name of the company was changed to Comptometer Corporation. However, in the difficulties following the Second World War, the manufacture of Comptometers in Britain was built up there due to restrictions on importing into that country Comptometers and many other manufactured goods. This profitable operation accounted for 25% of Comptometer's total production and this loss from it's Chicago plant seriously affected the profitability there.
In 1960, following a management reorganiation, the operation in England, including the right to the Comptometer name in England, was sold to Control Systems Ltd., which merged it with its own company to form Sumlock-Comptometer. Comptometer Corporation then contracted with Control Systems to have all its machines made by Control Systems in England and shipped back to the U.S.A. This resulted in all Comptometer production ceasing in Chicago in 1961.
There were financial difficulties at this time, exacerbated by the development costs of the Electrowriter, which resulted in a merger with Victor Adding Machine Company to form Victor Comptometer Corporation in 1961.


Example of a Comptometer

Comptometer model J

Comptometer model J, Sterling currency (£sd) version.

Vintage Calculators

© Text & photographs copyright Nigel Tout   2000-2015 except where noted otherwise.