Analog Computing Component - Barrel Gear


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.

Date Made: 1940s

Maker: Ford Instrument Company

Location: Currently not on view

Place Made: United States: New York, Queens, Long Island City

Subject: Mathematics


See more items in: Medicine and Science: Mathematics


Exhibition Location:

Credit Line: Ford Instrument Company, Division of Sperry Rand Corporation

Data Source: National Museum of American History

Id Number: 1982.0751.32Catalog Number: 1982.0751.32Accession Number: 1982.0751

Object Name: analog computing component

Physical Description: aluminum (overall material)plastic (tag material)Measurements: 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


Record Id: nmah_690600

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