Ford Instrument Company Ball & Disc Integrator

Description:

Instruments for finding the area bounded by curved lines (integrators) date from the nineteenth century. This twentieth century example is based on a mechanism invented by British engineer James Thomson and used by his brother William (later Lord Kelvin) in constructing the first harmonic analyzer in 1876. The object shows modifications and refinements made by the American inventor Hannibal Ford. It consists of a metal mechanism held in an aluminum frame painted white that is attached to a black bakelite base. The mechanism includes two (rather than just one) hardened steel balls that roll against one another. The bottom ball is turned by a disc on the bottom driven by an input gear. The top ball drives a roller.

A metal tag on the front of the base reads: 2 ½ Inch (/) BALL AND DISK (/) INTEGRATOR (/) Presented by (/) FORD INSTRUMENT COMPANY (/) DIVISION OF SPERRY RAND CORPORATION.

Ford's integrators were used in devices for aiming guns on ships of the U.S. Navy from about 1915 into the 1940s. The company merged with Sperry Corporation and, in 1955, became a subdivision of the newly established Sperry Rand Corporation. This object dates from after the establishment of Sperry Rand and before the donation of the object to the Smithsonian in 1961. A leaflet describes “Ford Precision DBR Integrators.” Here the acronym DBR is defined to mean “DIsk-Balls and Roller Integrator.”

Compare 1982.0751.06 and 1979.0751.36.

References:

“Ford Precision DBR Integrators,” no date.

Accession file.

A.B. Clymer, "The Mechanical Analog Computers of Hannibal Ford and William Newell," Annals of the History of Computing, 15, #2, 1993, 19-34.

Date Made: ca 1960

Maker: Ford Instrument Company

Location: Currently not on view

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

Subject: Mathematics

Subject:

See more items in: Medicine and Science: Mathematics, Mechanical Integrators and Analyzers

Exhibition:

Exhibition Location:

Credit Line: Gift of Ford Instrument Company

Data Source: National Museum of American History

Id Number: MA.319517Catalog Number: 319517Accession Number: 239018

Object Name: integrator

Measurements: overall: 11.5 cm x 30.8 cm x 25.6 cm; 4 17/32 in x 12 1/8 in x 10 3/32 in

Guid: http://n2t.net/ark:/65665/ng49ca746aa-947c-704b-e053-15f76fa0b4fa

Record Id: nmah_1214999

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