Comptograph - National Museum of American History
After inventing the Comptometer, Dorr E. Felt turned his attention to manufacturing a printing adding machine, which he dubbed the Comptograph. This early example is a full keyboard adding machine in a wooden case, with eight columns of metal keys covered with white discs.
Comptograph - National Museum of American History
At the back of the machine is a wide carriage, the printing mechanism for the adding machine, and a ribbon. This mechanism prints eight-digit entries and totals. A bell on top of each of the spools for the ribbon rings to warn that the ribbon is almost unwound.
Comptometer Explained – Everything You Need To Know
2023年7月27日 · The Comptograph was never as successful as the later Burroughs adding and listing machine, and it was phased out in the 1920s. However, several of Felt’s Comptograph inventions were licensed to others (including Burroughs), becoming the foundation of the “accounting machine” business.
Comptometer - Wikipedia
The Comptometer was the first commercially successful key-driven mechanical calculator, patented in the United States by Dorr Felt in 1887.
Comptometer Explained – Everything You Need To Know
2024年3月26日 · The Comptometer: A Revolutionary Calculating Machine That Transformed Business. The comptometer was the first commercially successful key-driven mechanical calculator and a revolutionary device that transformed bookkeeping, accounting and many other business processes for nearly a century.
John Wolff's Web Museum - Felt & Tarrant - The Comptometer
2014年4月5日 · The Comptograph never had the success of the later Burroughs adding and listing machine, and was discontinued in the 1920s. Several of Felt's Comptograph patents were licensed to others (including Burroughs), and eventually formed the basis of the "accounting machine" industry.
Dorr Felt - Wikipedia
During the US Thanksgiving holidays of 1884 he decided to build the prototype of a new calculating machine that he had invented. Because of his limited amount of money, he used a macaroni box for the outside box, and skewers, staples and rubber bands for …
Bookkeeping Machines | National Museum of American History
Beyond adding machines, the Burroughs Adding Machine Company sold bookkeeping machines, which carried out a wider range of accounting functions. This example was preserved in the company’s Patent Division.
John Wolff's Web Museum - Burroughs
The book "Origin of modern calculating machines" by engineer Joseph A.V.Turck (1921) discusses the mechanism and the development of the early Burroughs machines in relation to the Comptometer and the Comptograph.
NCR Bookkeeping Machines
The Early Office Museum covers combination typewriter-adding machines, also known as billing and bookkeeping machines, in the exhibit on Special Purpose Office Typewriters. One type of bookkeeping machine does not fit there, however: bookkeeping machines that were descendants of cash registers.