Comptograph
date: label: date made
content: 1889
name: label: maker
content: Felt & Tarrant Manufacturing Company
notes: label: Description
content: Not long after inventing the Comptometer, Dorr E. Felt of Chicago proposed a machine that would print the results of computations. This is an example of that machine, the Comptograph.
label: Description
content: The full keyboard printing manual adding machine has a case made out of cherrywood and eight columns of metal keys with white discs in the metal key tops. Digits and complements of digits are indicated on the discs. There are nine keys in each of the eight columns. A spring surrounds each key stem. The cover under the keys is made up of wooden slats with holes drilled in them, with one slat for each column of keys. Slats are alternately of cherry and a lighter-colored wood (possibly beech). In front of the keyboard is a shaped tin plate with 9 windows cut in it to reveal 9 metal wheels that record totals. A row of eight levers above the dials provides decimal markers.
label: Description
content: On the right side of the machine toward the front are a knob and a small lever. Depressing the lever allows one to turn the knob and zero the total wheels. To the right of the keyboard is a large button that advances the paper tape and ribbon. This tape and the mechanisms for printing the numbers entered and the totals are behind the keyboard. It appears that only eight-digit totals are printed. The paper tape is set inside a cherrywood lid that folds down when the machine is not in use. A knob on the right side at the back advances the carriage when loading paper. Compare to MA.323633.
label: Description
content: According to J. A. V. Turck, a machine of this type was at the National Museum in Washington in 1921. It seems likely that this is the machine he refers to, although the machine pictured by Turck more closely resembles MA.323633, which arrived later.
label: Description
content: Reference:
label: Description
content: J. A. V. Turck, <I>Origin of Modern Calculating Machines</I>, Chicago: Western Society of Engineers, 1921, pp. 116-120.
label: Location
content: Currently not on view
place: label: place made
content: United States: Illinois, Chicago
topic: label: Subject
content: Mathematics
setName: label: See more items in
content: Medicine and Science: Mathematics
label: See more items in
content: Adding Machines
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content: Science & Mathematics
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MA.322454
label: catalog number
content: 322454
label: maker number
content: 38
label: accession number
content: 247834
objectType: label: Object Name
content: adding machine
physicalDescription: label: Physical Description
content: metal (overall material)
label: Physical Description
content: wood (overall material)
label: Physical Description
content: paper (overall material)
label: Physical Description
content: cloth (overall material)
label: Physical Description
content: rubber (overall material)
label: Measurements
content: overall: 21.8 cm x 22.5 cm x 39.8 cm; 8 19/32 in x 8 27/32 in x 15 21/32 in