mirror galvanometer

measurement instrument

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Last updated

July 19, 2026

Quick Summary

A mirror galvanometer is an instrument used to measure small electrical currents. It operates by using the current's force to deflect a moving coil. This deflection is mechanically translated, often by a mirror attached to the coil, which reflects a beam of light. The angle of this reflected light beam indicates the magnitude of the electrical current flowing through the coil. This type of galvanometer is particularly sensitive and can detect very faint electrical signals.12

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William Thomson, Baron Kelvin
Early life
…his telegraph receiver, called a mirror galvanometer, for use on the Atlantic cable. (The device, along with his later modification called the siphon recorder, came to be used on most of the worldwide network of submarine cables.) Eventually the directors of the Atlantic Telegraph Company fired Whitehouse, adopted Thomson’s suggestions…
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…his telegraph receiver, called a mirror galvanometer, for use on the Atlantic cable. (The device, along with his later modification called the siphon recorder, came to be used on most of the worldwide network of submarine cables.) Eventually the directors of the Atlantic Telegraph Company fired Whitehouse, adopted Thomson’s suggestions…
Read More