Galvanometer Test Set (WWSSN)

Each of the 120 stations in the World Wide Standard Seismological Network used an instrument of this sort to test the sensitivity of its galvanometers. This one is marked “Geotech / Model 8431 / Galvo Test Set / Microamperes / Mfd by General Electric Co.” 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 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.
Ref: United States Coast and Geodetic Survey, Instrumentation of the World-Wide Seismograph System, Model 10700 (Washington, D.C., 1962).
Currently not on view
date made
General Electric Company
overall: 18.5 cm x 10 cm x 11 cm; 7 9/32 in x 3 15/16 in x 4 11/32 in
ID Number
accession number
catalog number
Credit Line
U.S. Geological Survey
related event
Cold War
See more items in
Medicine and Science: Physical Sciences
Measuring & Mapping
Science & Mathematics
Data Source
National Museum of American History


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