Analog Computing Component - Barrel Gear

Analog Computing Component - Barrel Gear

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This aluminum ballistic barrel cam is almost round on the bottom and more pointed on the top – though still with curved sides. It was made by Ford Instrument Company for the Computer Mark I, an analog device it built for the U.S. Navy. A mark on the more pointed end reads: u(V4)j (/) O.P. 1184 (/) 5”54CAL. 2550 F.S.I.V. Also on this surface is the mark: 596175. The center bearing hole is 1.8 cm. wide at each end. Each end also has three equally spaced shallow holes around the bearing hole. The small end also has a larger shallow hole with another small hole coming into this one from the cam side. A plastic tag stored with the object reads: 71 BALLISTIC (/) BARREL CAM.
A.B. Clymer, "The Mechanical Analog Computers of Hannibal Ford and William Newell," Annals of the History of Computing, 15, #2, 1993, 19-34.
Accession file.
Currently not on view
Object Name
analog computing component
date made
Ford Instrument Company
place made
United States: New York, Queens, Long Island City
Physical Description
aluminum (overall material)
plastic (tag material)
overall: 5.7 cm x 6.7 cm x 6.4 cm; 2 1/4 in x 2 5/8 in x 2 17/32 in
ID Number
catalog number
accession number
Credit Line
Ford Instrument Company, Division of Sperry Rand Corporation
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Medicine and Science: Mathematics
Data Source
National Museum of American History
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