Long-Period Galvanometer Control (WWSSN)

Each of the 120 stations in the World Wide Standard Seismological Network had three long-period control units for use with its three long-period galvanometers (such as 1999.0275.09). This one is marked “Galvanometer Control / Geotechnical Corp. / Garland, Texas / Model 12591 / Serial 17.” It was used at Georgetown University in Washington, D.C.
Established in the early 1960s, the WWSSN was a key component of VELA Uniform, a Cold War project that was funded by the Advanced Research Projects Agency (ARPA), a branch of the Department of Defense. The WWSSN was designed to detect underground nuclear tests and generate valuable information about the earth’s interior and its dynamic processes. It was managed first by the U.S. Coast and Geodetic Survey and then by the U.S. Geological Survey. That agency transferred this instrument to the Smithsonian in 1999.
Incorporated in 1936, the Geotechnical Corporation conducted research in and produced instruments for the earth sciences. It got into defense work after World War II, went public in 1962, and was bought by Teledyne in 1965.
Ref: United States Coast and Geodetic Survey, Instrumentation of the World-Wide Seismograph System, Model 10700 (Washington, D.C., 1962).
Currently not on view
overall: 14 cm x 10.3 cm x 20.2 cm; 5 1/2 in x 4 1/16 in x 7 15/16 in
ID Number
catalog number
accession number
Credit Line
U.S. Geological Survey
related event
Cold War
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Medicine and Science: Physical Sciences
Measuring & Mapping
Science & Mathematics
Data Source
National Museum of American History