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Development // Adders // Keyboard Adding Machines // Future of Computing

In 1885, Dorr Eugene Felt of Chicago invented the first mechanical multifunctional calculating machine that used a keyboard to input data.  Called the Comptometer, Felt built the first model out of a wooden macaroni box, meat skewers, wire, string, and rubber bands.  That prototype can be viewed today at the Smithsonian Institution in Washington, D. C.   Felt then constructed a metal version the next year for which he received a patent in March 1887.  Around that time, he formed a partnership with Robert Tarrant to manufacture and market the Comptometer.  Four of the first eight machines were purchased by the U.S. Treasury Department.  An illustrated ad of the machine in the July 20, 1895 issue of Harper’s Weekly, under the headline “The Measure of Progress,” featured a bookkeeper tabulating accounts at his desk.  The design of the machine itself can be seen clearly in an ad in the October 12, 1907 issue.  As the ad text pointed out, all Comptometer functions were performed on a keyboard without pulling a lever after each data entry, as necessitated by the product’s rivals.  Comptometers were still in use in the 1950s at a leading New York City department store and other businesses. 

One of the leading lever-entry keyboard calculators was the Universal Adding Machine manufactured in St. Louis, Missouri.  The machine’s large handle on its right side was discernable in an illustrated advertisement in the March 21, 1908 Harper’s Weekly.  The ad text claimed that subsequent computations could be set up while the lever was only two-thirds of the way back, thereby allowing entries to be made more swiftly than with other lever-operated models.  The Universal printed the calculations on a paper roll, but also had a paper feed for loose-leaf or carbon paper.  The same year that the ad appeared, Universal Adding Machine Company was purchased by the Burroughs Adding Machine Company. 

William S. Burroughs had also invented a multifunctional calculating machine with a keyboard in 1885, but did not receive a patent until 1888—a year after Felt was awarded his for the Comptometer.  In 1886, Burroughs and three other men founded the American Arithmometer Company to sell his invention.  After the product failed at several competitive trials, Burroughs was awarded a patent in 1892 on an improved version modeled partly on Felt’s Comptometer.  The company began seeing greater market success in the late 1890s, despite the death of Burroughs in 1898.  In 1905, the firm changed its name to Burroughs Adding Machine Company, and sold a million machines over the next 20 years to become the nation’s largest manufacturer of adding machines.  An eye-catching ad in the March 20, 1909 issue of Harper’s Weekly emphasized “The Small Price for Enduring Accuracy:  7¢ Per Day.”  It also offered a free efficiency manual, “A Better Day’s Work,” with purchase of an adding machine.

Beginning in 1904, various manufacturers produced machines combining the functions of an adding machine and a typewriter, which were marketed with various descriptive terms, such as “typewriter-adding,” “typewriter-billing,” “type-bookkeeping,” and “writing-adding.”  In 1909, the Remington Typewriting Company introduced a model with a Wahl Adding and Subtracting Attachment.  It was marketed as “The Machine Which Does It All,” listing numerous office duties that the machine could handle, including bills, payrolls, invoices, and sales analyses.

Harper's Weekly References
1) July 20, 1895, p. 693, col. 2-3
illustrated ad, adding machine, Comptometer

2) October 12, 1907, p. 1503, col. 2
illustrated ad, adding machine, Comptometer

3) March 21, 1908, p. 27, col. 2
illustrated ad, Universal Adding Machine

4) March 20, 1909, p. 34, col. 3-4
illustrated ad, Burroughs Adding Machine

5) June 5, 1909, p. 2, col. 2
illustrated ad, Remington typewriter/adding machine

Sources Consulted

“Comptometer:  Biography of a Machine.”

Hancock, Michael.  “Burroughs Adding Machine Company, History—1857-1953.”

Redin, James.  “A Brief History of Mechanical Calculators.”

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