The Comptometer was invented by the American Dorr Eugene Felt and was patented in 1887. Manufactured by the Felt and Tarrant Manufacturing Company  of Chicago, the Comptometer was the first truly practical and commercially successful key-driven adding machine. They proved very successful and were developed and manufactured in large numbers up until the early 1970s.

"Comptometer" eventually became to be used as a generic name for calculators of this type from other manufacturers, but technically it was a brand name that only a few companies had the rights to use.

The main manufacturers of Comptometer type machines were:

• Felt & Tarrant (later Comptometer Corporation, and Victor Comptometer), the original manufacturer.
• Burroughs Adding Machine Co., Detroit, U.S.A.
• Bell Punch Co., Uxbridge, England. Sold under the names Plus, Sumlock, and Sumlock Comptometer.

We believe this example in our collection to be the Sterling currency version of the model J. It was very kindly donated by Elsie Bennett and is in excellent working condition.

Manufacturer: Felt & Tarrant
Date: 1913

This exhibit has a reference ID of CH29895. Please quote this reference ID in any communication with the Centre for Computing History.

Click on the Image(s) For Detail