Comptometer Model E


This full-keyboard non-printing adding machine has a brown metal case, eight rows of plastic keys for entering numbers that are colored according to the place value of the digits entered, eight subtraction levers with decimal markers, and a row of nine windows at the front of the machine to show the result. Complementary numbers are indicated on the keys. Keys for odd digits are concave, and those for even ones are flat. There is a button on the upper right of the keyboard and a zeroing lever on the right side. The machine featured an error-locking mechanism. Metal “wings” extending on the right and left side of each key are introduced as part of an “individual key lock” mechanism.

The machine has serial number 61612. The last patent date on the metal tag behind the keyboard is: JUN.7.10.


Felt & Tarrant, Accession Journal, 1991.3107.06.

Date Made: 1913

Maker: Felt & Tarrant Manufacturing Company

Location: Currently not on view

Place Made: United States: Illinois, Chicago

Subject: Mathematics

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


Exhibition Location:

Credit Line: Gift of Victor Comptometer Corporation

Data Source: National Museum of American History

Id Number: MA.323647Maker Number: 61,612Catalog Number: 323647Accession Number: 250163

Object Name: adding machine

Physical Description: metal (overall material)plastic (overall material)wood (overall material)Measurements: overall: 14 cm x 24 cm x 36.2 cm; 5 1/2 in x 9 7/16 in x 14 1/4 in


Record Id: nmah_690471

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