TIM Calculating Machine


This manually operated, non-printing stepped drum calculating machine has a brass and steel mechanism, eight zinc alloy stepped drums, one of them cracked, and iron sides. The drums are only half-cylinders. On top of the drums is a metal plate painted black with slits for sliding levers used to set digits. The digits from 0 to 9 are marked along the edge of each slit. Six of the levers have steel bands next to them with the digits 0 to 9 stamped on them. These bands move so that the number set appears in a row of windows over the levers. The digit indicator is missing for the sixth and eighth windows.

On the carriage are nine windows in the revolution counter and 16 to show the result. The crank at the right is broken and has no handle. Decimal markers include one flimsy painted metal piece for numbers entered, one for the revolution counter, and three for the result. The add & multiply / subtract & divide lever is on the left, but has broken off. The stepped drums are not covered on the underside.

A mark below the entry levers reads: Rechenmaschinenfabrick LUDWIG SPITZ & Co., G.m.b.H., Berlin - Wien - New-York. A mark on the front of the machine reads: TIM. A mark at the left reads: PATENT (/) BREVET. A mark on the front edge of the carriage near the zeroing knobs reads: 828. A mark under the carriage reads: 01153. Another mark reads: Ludwig Spitz & Co. (/) TIM (/) TIME IS MONEY (/) TRADE MARK .

This is a TIM machine removed from a wooden case and placed on an iron stand, but without the central plate and other features of later TIM machines. The TIM was introduced in 1907 and first sold in a cast-iron housing in 1909.

The donor inherited this machine from his father.


Accession file 1994.0092.

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

Date Made: ca 1909

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 Philip W. Steiner

Data Source: National Museum of American History

Id Number: 1994.0092.01Catalog Number: 1994.0092.01Accession Number: 1994.0092Maker Number: 01516

Object Name: calculating machine

Physical Description: iron (overall material)brass (overall material)aluminum (overall material)Measurements: overall: 13.6 cm x 54.5 cm x 18 cm; 5 11/32 in x 21 15/32 in x 7 3/32 in

Guid: http://n2t.net/ark:/65665/ng49ca746a5-16cc-704b-e053-15f76fa0b4fa

Record Id: nmah_690672

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