Signedon base between the binding posts: LEEDS & NORTHRUP CO. / PHILADELPHIA PA
Inscribedon base, front (serial number): 220749
moulded flap swings out from underneath the base with the meter's specifications (see Card)
on case, top: MADE IN U.S.A.
FunctionReflecting galvanometers are used to measure very small electrical currents and voltage differences. Instead of having a scale with a pointer, in these galvanometers 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. Alternatively, a scope is pointed at the mirror to see the change in the angle that the scope points to on a scale seen through the mirror. In those cases, the scales that are used are mirror-inverted.
ProvenanceFrom Byerly Laboratory (Harvard University), 10/13/1964. Was used in undergraduate experiments when many of the classes were given there.