Toepfer Variometer

This variometer, which measures slight changes in magnetic declination, is based on a design developed by J. F. A. M. Eschenhagen, Director of the Prussian Magnetic Observatory at Potsdam. This example is marked "Otto Toepfer & Sohn Potsdam XIII." The U.S. Coast and Geodetic Survey obtained several instruments of this sort from Toepfer around 1901 and kept them in use for many years. The U.S. Geological Survey acquired this example in 1973 when it assumed responsibility for the geomagnetic program of the federal government, and transferred it to the Smithsonian in 1982.
Ref: M. Eschenhagen, "Magnetic Intensity Variometers," Terrestrial Magnetism 5 (1900): 59-62.
Otto Toepfer & Sohn, Neue transportable Feinregistrir-Einrichtung für Erdmagnetismus (Potsdam, 1903).
Daniel Hazard, Results of Observations Made at the Coast and Geodetic Survey Magnetic Observatory at Baldwin, Kansas, 1901-1904 (Washington, D.C., 1909), pp. 10-11.
Currently not on view
Object Name
Otto Toepfer & Sohn
Physical Description
metal (overall material)
overall: 19 1/2 in; 49.53 cm
Place Made
Deutschland: Brandenburg, Potsdam
ID Number
accession number
catalog number
Measuring & Mapping
Science & Mathematics
Science & Scientific Instruments
Science & Scientific Instruments
See more items in
Medicine and Science: Physical Sciences
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
U.S. Department of the Interior, U.S. Geological Survey

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