Magnetometer

Object Details

T. Cooke & Sons Ltd.

Description

This instrument, a lighter and more robust version of the standard unifilar magnetometer used at the Kew Observatory, was designed by H. A. Denholm Fraser for the Magnetic Survey of India. Features include scales graduated on optical glass, and a phosphor-bronze ribbon to suspend the magnet. This example is marked "T. COOKE & SONS LTD. LONDON & YORK. No. 26" and "U.S.C.& G.S. No. 40." It was used at the U.S. Coast and Geodetic Survey's magnetic observatory in Honolulu from 1927 to the 1950s. The U.S. Geological Survey acquired it in 1973, when it took over the geomagnetic program of the federal government, and transferred it to the Smithsonian in 1982.

Thomas Cooke began in business in York, England, in 1837. The firm became T. Cooke & Sons in 1868, and T. Cooke & Sons Ltd. in 1897. A merger with Troughton & Simms Ltd. in 1922, led to the formation of Cooke, Troughton & Simms Ltd.

Photograph 82-15291 shows this magnetometer fitted with the induction apparatus developed by J. H. Nelson in 1938.

Ref: H. A. Denholm Fraser, "The Unifilar Magnetometer of the Magnetic Survey of India," Terrestrial Magnetism 6 (1901): 65-69.

T. Cooke & Sons, Illustrated Catalogue of Surveying Instruments, etc. (London, 1907), pp. 62-63.

Anita McConnell, Instrument Makers to the World. A History of Cooke, Troughton & Simms (York, 1992), pp. 69-70.

Location

Currently not on view

Credit Line

U.S. Department of the Interior, U.S. Geological Survey

ID Number

1982.0671.02

accession number

1982.0671

catalog number

1982.0671.02

Object Name

magnetometer

Physical Description

metal (overall material)

wood (part material)

Measurements

horizontal circle: 6 in; x 15.24 cm

overall in case: 11 1/2 in x 22 1/8 in x 14 1/2 in; 29.21 cm x 56.1975 cm x 36.83 cm

Place Made

United Kingdom: England, London

United Kingdom: England, Jorvik

See more items in

Medicine and Science: Physical Sciences

Science & Mathematics

Measuring & Mapping

National Museum of American History

Subject

Science & Scientific Instruments

Science & Scientific Instruments

Record ID

nmah_1029288

Metadata Usage (text)

CC0

GUID (Link to Original Record)

https://n2t.net/ark:/65665/ng49ca746a8-e610-704b-e053-15f76fa0b4fa