(December 17 1797 May 13 1878
) was an American scientist. While building electromagnets, he discovered the electromagnetic
phenomenon of self-inductance
. He also discovered mutual inductance, independently of Faraday
, but Faraday was the first to publish his results. His work on the electromagnetic relay was the basis of the electrical telegraph
, jointly invented by Morse
The SI unit of inductance, the henry, is named after him.