Portable reflecting galvanometer

Made by Leeds & Northrup Co in Philadelphia, Pennsylvania, United States of America, 1938-1946.

The first galvanometer was built in Germany by Johann S. Schweigger in 1820. It is a device used to measure low-level electric currents by electromechanical action. A mirror galvanometer is a mechanical meter that senses electric current, except that instead of moving a needle, it moves a mirror. In the D’Arsonval design the coil has many turns of fine wire, and is suspended by a flat ribbon of wire which serves as one lead-in wire.

Although many have been replaced by electronic instruments, ga...


This is a portable, D'Arsonval type moving coil reflecting galvanometer, contained in a painted grey wooden box, with two sets of terminals mounted on the exterior of the box, two for connection of a 6-volt AC or DC power source, and the other two for test connection.

The top of the box hinges back to show a horseshoe magnet lying horizontally. The galvanometer system is a light coil assembly with a pivotable mirror suspended between the poles of the horseshoe magnet.

D'Arsonval type galvanometers operate by means of a light coil of wire being suspended from a metal ribbon a few thousandths of a millimetre wide and less than 0.02mm thick. The light system comprises a lamp, lamp-holder and lens assembly. Mirror and light assembly operate in the same plane, to reflect the light beam on to a frosted glass panel on the front inside of the box. The glass panel is marked with a scale graduated in millimetres. The coil, which can freely rotate between the permanent magnet poles carries the small mirror which acts as the optical pointer, showing the coil position. Current is conducted to and from the coil by the suspension ribbons.

A galvanometer is an instrument for detecting and measuring electric current. It is an electromechanical transducer that produces a rotary deflection through a limited arc in response to electric current flowing through its coil.


137 mm
140 mm
220 mm


This galvanometer was made by Leeds & Northrup Co, in Philadelphia, Pennsylvania, United States of America, 1938-1946.

Leeds & Northrup was established in 1903 when Edwin Northrup joined the Morris E. Leeds Company. Leeds & Northrup was bought out by the Foxboro Company, now called APV Australia Pty Ltd.
Leeds & Northrup Co 1938-1946


Gift of Foxboro Australia, 2007
7 November, 2007

Cite this Object

Portable reflecting galvanometer 2016, Museum of Applied Arts & Sciences, accessed 19 November 2017, <https://ma.as/348835>
{{cite web |url=https://ma.as/348835 |title=Portable reflecting galvanometer |author=Museum of Applied Arts & Sciences |access-date=19 November 2017 |publisher=Museum of Applied Arts & Sciences, Australia}}
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