Variometer
name: label: maker
content: Ruska Instrument Corporation
notes: label: Description
content: This variometer measures slight changes in the vertical component of the earth's magnetic field. The surrounding Helmholtz coil enables its scale value to be determined electrically. This example is marked "RUSKA INSTRUMENT CORPORATION HOUSTON TEXAS No. 5728 MADE IN U.S.A." The U.S. Coast and Geodetic Survey acquired it in 1957, probably for use during the International Geophysical Year. The U.S. Geolgical Survey acquired it in 1973 when it assumed responsibility for the geomagnetic program of the federal government, and transferred it to the Smithsonian in 1982.
label: Description
content: Ref: Ruska Instrument Corporation, <i>Magnetic Instruments</i> (Houston, 1955).
label: Location
content: Currently not on view
place: label: Place Made
content: United States: Texas, Houston
topic: label: Subject
content: Science & Scientific Instruments
label: Subject
content: Science & Scientific Instruments
setName: label: See more items in
content: Medicine and Science: Physical Sciences
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content: Science & Mathematics
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content: Measuring & Mapping
creditLine: label: Credit Line
content: U.S. Department of the Interior, U.S. Geological Survey
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1982.0671.13a
label: accession number
content: 1982.0671
label: catalog number
content: 1982.0671.13a
objectType: label: Object Name
content: variometer
physicalDescription: label: Physical Description
content: metal (overall material)
label: Measurements
content: overall: 19 in; 48.26 cm
label: Measurements
content: overall: 8 7/8 in x 12 1/4 in; 22.5425 cm x 31.115 cm