Michael Faraday — 150 years after the discovery of electromagnetic induction

Abstract

On August 29^th, 1831 Michael Faraday discovered electromagnetic induction. He realized for the first time that a variable current in one circuit could induce a current in a second and isolated circuit. Since this discovery fills only a few lines in Faraday’s Laboratory Note Book (his Diary, as he named it), and since this Diary has been published, under the patronage of Sir William H. Bragg, by the Royal Institution of Great Britain, it may be appropriate to quote the relevant passages verbatim: “Have had an iron ring made (soft iron), iron round and 7/8 inches thick and ring 6 inches in external diameter. Wound many coils of copper wire around one half, the coils being separated by twine and calico ..., will call this side of ring A. On the other side but separated by an interval was wound wire in two pieces together amounting to about 60 feet in length, the direction being as in former coils; this side call B.”

Lecture in Geneva, February 22, 1982.