Note 11 — Chapter X · ELECTROMAGNETIC INDUCTION

NOTE.—Faraday’s own description of his discovery is as follows: “Two hundred and three feet of copper wire in one length were coiled round a large block of wood; another two hundred and three feet of similar wire were introposed as a spiral between the turns of the first coil, and metallic contact everywhere prevented by twine. One of these helices was connected with a galvanometer, and the other with a battery of one hundred pairs of plates, four inches square, with double coppers, and well charged. When the contact was made there was a sudden and very slight effect at the galvanometer, and there was also a similar slight effect when the contact with the battery was broken.”