Click on the images below to see them at full scale.
The Quervain-Piccard mechanical 3-component seismograph
The springs. Valerie for scale.
The view from the second story
Jean-Marie Saurel looks for the on switch
Damping & recording drum – side view. Damping removes the free oscillation of the pendulum allowing the Quervian-Piccard to record ground motion. The recording drum would have been smoked over a diesel flame by a technician, carbon coating the paper. The needle would have then etched the ground motion into the carbon. After the paper was full, the technician would have removed it and passed it through varnish thus fixing the carbon to the paper.
the mass suspended by the four springs. 220 cast iron plates each weighing between 70 and 95 kg constitute the 20 ton mass.
Click to enlarge
Alfred de Quervain, the man who built the first portable seismograph. SRC: UPI
For all of the details see:
- de Quervain, A. & Piccard, A., 1924. Beschreibung des 21-Tonnen-UniversalSeismographen System de Quervain – Piccard, Jahresber. Schweiz. Erdbebendienst
- de Quervain, A. & Piccard, A., 1927. Déscription du séismographe universel de 21
tonnes système de Quervain-Piccard, Publ. Bureau Centr. Séism. Int. Sér. A, 4(32).
(thanks Erhard Wielandt)
Click here for a stellar document on old-school seismic instrumentation.