TIM Calculating Machine


This heavy, stepped drum, full-keyboard electric calculating machine has a metal frame painted black and green, and eight columns of black and white plastic numeral keys. The carriage is in back of the machine, with nine revolution counter wheels and sixteen result wheels. Both the revolution counter and the result register have sliding decimal markers. Digits can be set in the revolution register using thumbscrews. A bell rings when the result passes through 0.

The machine sits on a metal stand, also painted black, which holds the machine above and the motor below. The nine silver-colored metal digit keys below the keyboard toward the front of the stand are numbered from left to right. The crank for operating the machine manually is to the right of the keyboard. Left of the keyboard is a lever that can be set for addition/multiplication or subtraction/division. The cord is on the right front of the machine.

A mark on the carriage reads: Ludwig Spitz & Co. (/) G.m.b.H. (/) T I M (/) TIME IS MONEY (/) TRADE MARK. A small metal tag attached below the row of metal keys at the front of the machine reads: 860. The machine is stamped on the left side underneath the carriage: 12571.

The Berlin maker Ludvig Spitz began his business offering sturdy, manually operated, stepped drum calculating machines. After World War I, he introduced key-set machines like this one. The example comes from the collections of Felt & Tarrant Manufacturing Company.


E. Martin, The Calculating Machines (die Rechenmaschinen), trans. P. A. Kidwell and M. R. Williams, Cambridge: MIT Press, 1992, pp. 191–194.

Date Made: 1920s

Maker: Ludwig Spitz & Co.

Location: Currently not on view

Place Made: Germany: Berlin, Berlin

Subject: Mathematics


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


Exhibition Location:

Credit Line: Gift of Victor Comptometer Corporation

Data Source: National Museum of American History

Id Number: MA.323587Accession Number: 250163Maker Number: 860Catalog Number: 323587

Object Name: calculating machine

Physical Description: cloth (overall material)plastic (overall material)metal (overall material)Measurements: overall: 40.5 cm x 58 cm x 32 cm; 15 15/16 in x 22 27/32 in x 12 19/32 in

Guid: http://n2t.net/ark:/65665/ng49ca746a5-0f7b-704b-e053-15f76fa0b4fa

Record Id: nmah_690621

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