Johann S. Schweigger

From ETHW

Biography

Born: April 8, 1779

Died: Sept. 6, 1857

Johann S. Schweigger was a German chemist and physicist who invented the first galvanometer, a tool for measuring the strength and direction of electric current.

Schweigger was born in Bavaria, Germany, in 1779. He received his doctorate from the University of Erlanger in 1800 and spent his academic career at the Gymnasium of Bayreuth, the Polytechnic School of Nuremberg, and the University of Halle.

He started the Journal for Chemistry and Physics in 1811 and continued to co-edit it until 1828. During these years, the study of electromagnetism was advancing through the research of Andrew-Marie Ampere, Hans Oersted, and William Wollaston. As a journal editor, Schweigger was exposed to these ideas and pursued his own experiments in magnetism. Inspired by Oersted, Schweigger created a device to measure electrical current by wrapping a coil of wire around a magnetic compass needle. It was initially called a “multiplier” because the effect of the magnetic field increased as the number of turns of wire multiplied.

He presented this device, which would later be renamed a galvanometer after Italian physicist Luigi Galvani, in paper at the University of Hall on September 16, 1820. Meanwhile, two other scientists—Johann Poggendorff of Berlin, Germany, and James Cumming of Cambridge, England—independently invented similar multipliers in 1821.