Editing Comptometer (section)

===Comptometer and comptograph===
[[Image:Mechanical-Calculator.png|thumb|left|<div align="center">Comptograph (1914)</div>]]

The original comptometer design was patented by the American Dorr E. Felt. The first two patents were granted on July 19, 1887<ref>[https://patents.google.com/patent/US366945 U.S. Patent No. 366,945], filed on July 6, 1886</ref> and on October 11, 1887.<ref>[https://patents.google.com/patent/US371496 U.S. Patent No. 371,496], filed on March 12, 1887</ref>

Two years later, on June 11, 1889, he was granted a patent for the Comptograph.<ref>[https://patents.google.com/patent/US405024 U.S. Patent No. 405,024], filed on January 19, 1888</ref>  A Comptograph is a comptometer with a printing mechanism making it more like a key-set calculating machine (even though the keys are registered as they are typed and not when a handle is pulled), therefore slower and more complicated to operate. It was the first printing-adding machine design to use individualized type impression which made its printed output very legible.

The first comptograph was sold to the Merchants & Manufacturers National Bank of Pittsburgh, PA. in December 1889. It was the first sale of a {{nowrap|recording-adding}} machine ever. This machine is now on display at the Smithsonian Institution in Washington, D.C..

The Felt & Tarrant Manufacturing Company built both comptometers and comptographs throughout the 1890s. In 1902, the Comptograph Company was set up to manufacture comptographs exclusively, but was shut down at the beginning of [[World War I]].

Forty years later, in the mid-1950s, the Comptometer Corporation reused the name Comptograph for a line of 10-key printing machines.