Astatic Galvanometer by Central Scientific Co.

Astatic Galvanometer, late 19th century. Made by Central Scientific Company. Good condition. Galvanometer with magnetized needle above and in fixed coils. An aluminum pointer attached to needles is suspended by a thread above paper scale graduated from 0°-90°-0°-90°-0°. L-shaped brass suspension support. Coils rest on circular brass base, with two binding posts and three leveling screws. A bell jar enclosure covers the meter.

Astatic Galvanometers are precision instruments used to detect small electric currents by generating a magnetic field. Thereby changing the direction of a suspended compass needle. From measuring the deflection of the compass needle from true North, the electric current can be detected, as well as it's relative strength (if needle moves completely around, the charge is greater- if the needle barely moves, the charge is smaller). As telescopes first showed us the macro world, astatic galvanometers first showed us the micro world. This instrument was a first for sensitive and quantitative electrical data, paving way for the incredible advancements in electron studies and technological innovations ever since. 

Weight: 1 lb. 3 oz. 

Dimensions: 5.0” x 4.5” x 6.5”