Comptometer, Macaroni Box Model


This is the prototype for the Comptometer, a key-driven adding machine invented by Dorr E. Felt of Chicago. It is a scarred wooden box (originally used to transport macaroni) that contains the levers and wheels for a 5-column adding machine with one partial column of keys (wooden skewers), four of which are missing. The number dials are at the front. Two screws are on the top of the back panel. A series of rubber bands, used to set the levers to accept the next keystroke, are missing.

Compare to replica, which has catalog number MA.323646.


J. A. V. Turck, Origin of Modern Calculating Machines, Chicago: Western Society of Engineers, 1921, pp. 52-56.

Date Made: 1884-1885

Maker: Felt, Dorr E.

Place Made: United States: Illinois, Chicago

Subject: Mathematics


See more items in: Medicine and Science: Mathematics, Adding Machines, Science & Mathematics

Exhibition: Inventing In America

Exhibition Location: National Museum of American History

Credit Line: Gift of the Heirs of Dorr E. Felt

Data Source: National Museum of American History

Id Number: MA.311192Catalog Number: 311192Accession Number: 143207

Object Name: adding machine

Physical Description: wood (overall material)cork (overall material)metal (overall material)Measurements: overall: 25 cm x 20 cm x 52.5 cm; 9 27/32 in x 7 7/8 in x 20 21/32 in


Record Id: nmah_690461

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