Signedunsigned
Inscribedstamped on upper right corner of wooden base: 17 / PHYSICS 3
stamped on smaller wooden plank: 2800 OHMS
FunctionWall-mounted galvanometer consists of a coil that has been wound with very fine wire mounted between the poles of a permanent U magnet. A small mirror turns in the presence of electrical currents. The change of angle can be detected by shining a light at the mirror and observing the reflection on a large scale that is placed in front of the device.
ProvenanceFrom the Department of Physics, Lyman Laboratory attic, Harvard University, 12/12/1971.