Long-Period Vertical Seismometer (WWSSN)
date: label: date made
content: 1961-1962
name: label: maker
content: W. F. Sprengnether Instrument Co.
notes: label: Description
content: Working at the Lamont Geological Observatory, a Columbia University facility in Palisades, N.Y., Frank Press and his mentor, Maurice Ewing, developed seismometers that responded to surface waves of long-period and small-amplitude, whether caused by explosions or by earthquakes. The first long-period vertical seismometer at Lamont came to public attention in early 1953 with news that it had recorded waves from a large earthquake that had recently occurred at Kamchatka, in the Soviet Union. A painting of a subsequent but similar Lamont instrument appeared on the cover of <i>Scientific American</i> in March 1959.
label: Description
content: This example was made for the World Wide Standard Seismological Network. Established in 1961, the WWSSN was designed to detect underground nuclear tests and generate valuable information about the earth’s interior and its dynamic processes. 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. 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.
label: Description
content: Each of the 120 WWSSN stations had an instrument of this sort. This example was used in Junction City, Tex. It would have been linked to a matched galvanometer (such as 1999.0275.09) and a photographic drum recorder (such as 1999.0275.10). The “Sprengnether Instrument Co.” signature refers to a small shop in St. Louis, Mo., that specialized in seismological apparatus.
label: Description
content: Like other long-period vertical seismometers developed at Lamont, this one was built around a “zero-length spring” of the sort that had been proposed in 1934 by Lucien LaCoste, a graduate student in physics at the University of Texas, and later incorporated into the gravity meters manufactured by LaCoste & Romberg.
label: Description
content: Ref: United States Coast and Geodetic Survey, <i>Instrumentation of the World-Wide Seismograph System, Model 10700</i> (Washington, D.C., 1962)
label: Description
content: Ta-Liang Teng, “Seismic Instrumentation,” in <i>Methods of Experimental Physics</i>, vol. 24 part B, <i>Geophysics</i> (1987), pp. 56-58.
label: Location
content: Currently not on view
place: label: place made
content: United States: Missouri, Saint Louis
topic: label: related event
content: Cold War
setName: label: See more items in
content: Medicine and Science: Physical Sciences
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content: Seismographs
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content: Science & Mathematics
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content: Measuring & Mapping
creditLine: label: Credit Line
content: U.S. Geological Survey
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1999.0275.03
label: catalog number
content: 1999.0275.03
label: accession number
content: 1999.0275
objectType: label: Object Name
content: seismometer
physicalDescription: label: Measurements
content: overall: 25 in x 15 in x 26 in; 63.5 cm x 38.1 cm x 66.04 cm