Eötvös Torsion Balance

Torsion balances are used to measure weak natural forces. Torsion balances generally consist of a straight rod with masses attached to each end, suspended from a wire. It is then encased in metal to isolate it from temperature or wind disturbance. All mass near or far has an influence on the rod, but the wire resists this force and twists in the opposite direction, producing through its twisting the measurements of the forces imposed upon it.
Although torsion balances had been used for physics experiments since the 1780s, their development for geophysical purposes began with the Hungarian nobleman, Loránd (Roland) von Eötvös (1848– 1919), a professor of physics at the University of Budapest. An Eötvös torsion balance suitable for field work won an award at the international exposition held in Paris in 1900. Within a few years, several European scientists were using instruments of this sort for geodetic work (the study of measuring and representing the Earth), and Hugo de Boeck, director of the Hungarian Geological Survey, was urging that they be used for geological work as well. An Eötvös torsion balance was used in the first gravimetric survey for petroleum prospecting that occurred in the Egbell field in Slovakia in 1915 1916. The American prospector Everette De Golyer tried to obtain an Eötvös torsion balance at that time but the Great War stymied his efforts. De Golyer received his first torsion balances from Budapest in 1922.
Eötvös' original torsion balance could determine the gravitational gradient in only one direction at a time. In 1906 he described a double instrument that consisted of two balances placed 180 degrees from one another, and that substantially shortened the time needed to determine the gravitational gradient. This example is of that sort. It was probably made by Ferdinand Süss, the artisan who made many instruments for Eötvös. The Eötvös Loránd Geophysical Institute in Budapest is active to this day.
The Humble Oil & Refining Co. purchased this torsion balance from the Baron Von Eötvös Company in 1925, and sent Arnold Romberg, professor of physics at the University of Texas, at Austin, to Budapest to learn about it. Humble then used it for oil exploration on the Gulf Coast of Texas and Louisiana until the introduction of gravimeters in 1936.
Ref: H. Shaw and E. Lancaster-Jones, "The Eötvös Torsion Balance," Proceedings of the Physical Society of London 35 (1923): 151-166.
Currently not on view
date made
place made
Magyarország: Budapest, Budapest
overall: 32 in x 10 1/2 in; 81.28 cm x 26.67 cm
ID Number
catalog number
accession number
Credit Line
Humble Oil and Refining Company
See more items in
Work and Industry: Agriculture and Natural Resources
Measuring & Mapping
Data Source
National Museum of American History, Kenneth E. Behring Center


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