Three-Channel Drum Photographic Recorder (WWSSN)

Each of the 120 stations in the World Wide Standard Seismological Network had several drum recorders that, covered with photographic paper, recorded the three components (one vertical and two horizontal) of seismic phenomena. This three-channel recorder would have been used with the three long-period seismometers. It is marked “United Electro Dynamics Inc. / United GeoMeasurements Division / Pasadena California / Recorder, Photographic / Model No. DR 275 / Part No. 217205 / Serial No. 11.” 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.
As the chief engineer of the Seismological Laboratory at the California Institute of Technology, Francis Lehner helped the scientists in that Pasadena institution design and make their instruments. Working with his nephew, Bob Griffith, he made seismological apparatus for other organizations. In 1960 after receiving a substantial contract to produce equipment for VELA Uniform, Lehner & Griffith became the core part of the United GeoMeasurements Division of United ElectroDynamics, a much larger defense contractor that was also located in Pasadena. In 1964 when United ElectroDynamics was sold to Teledyne, the seismological operations were merged with those of the Geotechnical Corporation. The seismic instrument designers and makers of United ElectroDynamics who refused to move to Texas then formed Kinemetrics.
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
United ElectroDynamics
place made
United States: California, Pasadena
overall: 35 cm x 139 cm x 44 cm; 13 25/32 in x 54 23/32 in x 17 5/16 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


Add a comment about this object