ID: 
38
Maker's Name: 
Griffin, London
Where made: 
England
Dimensions: 
17 × 20.5 × 19.5 cm

In this instrument the coil in enclosed in a thin-walled tube, to the upper end of which the optically worked concave mirror is attached. It is suspended so that it swings in the narrow gap between the poles of a powerful permanent magnet. Owing to its long narrow shape the coil has a very small moment of inertia and the instrument is extremely sensitive. The suspension mount fits into a socket in the base of the galvanometer, and the suspended system can this be instantly changed for another of different resistance or period. (From Griffin catalogue)

The white (ivory) tube in this instrument suggests it was used as a ballistic galvanometer.