2 images. California Institute of Technology's seismic tape recorder...Turns temblor energy into sound, 21 November 1951. Doctor Hugo Benioff, In Charge of Instrumentation for the Seismographic Laboratory.; Supplementary material reads: "Memo: 1951-11-20. Captions for earthquake story for Thanksgiving. Picture A shows Dr. Hugo Benioff, in charge of instrumentation for the seismo lab, operating the tape recorder, which transforms vibratory movement of earth into small amount of electrical power. Picture B shows tape being run through a playback mechanism which magnifies seismic waves 600 times so they can be heard".