Burns Addometer

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This U.S. patent model for a lever-set non-printing adding machine has wooden sides and metal covers for the back and the lower front. Four large toothed wheels are used for setting numbers, with five registering wheels in front and below these. Between each of the large wheels is a strip of metal; the digits from 0 to 9 are indicated along the edges of these strips. Each of the four right registering wheels is attached to a spur wheel with ten teeth that meshes with a large toothed wheel. Placing a finger in one of the teeth of a large wheel and rotating it forward advances the registering wheel proportionally. The number entered is visible in a row of windows at the front of the model. The four registering wheels to the left have on their left side a ring of ten equidistant pins that are used in carrying.
The patent tag for the machine reads: 21243 (/) J. Burns (/) Addometer (/) Patented Aug 24 (/) 1858 (/) Calculator.
On March 26, 1867, Jabez Burns of New York City took out U.S. Patent 52934 for an improved powder mixer. The model for this patent is in the Medical Sciences collection of the Smithsonian’s National Museum of American History. It seems likely that this is the same person who invented the addometer and the same Jabez Burns who was born in Ireland in about 1827, came to new York at age 18 in January of 1845, and worked variously as a cartman, peddler, accountant, and inventor. He had a son, also called Jabez Burns.
Jabez Burns, "Addometer," U.S. Patent 21243, August 24, 1858.
U.S. Census records 1850, 1860. Civil War draft regisration records, June, 1863. New York City directories.
Currently not on view
date made
Burns, Jabez
place made
United States: New York, New York
Physical Description
wood (overall material)
tin (overall material)
brass (overall material)
paper (overall material)
overall: 16 cm x 38.7 cm x 12.2 cm; 6 5/16 in x 15 1/4 in x 4 13/16 in
ID Number
accession number
catalog number
See more items in
Medicine and Science: Mathematics
Science & Mathematics
Adding Machines
Data Source
National Museum of American History


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