60. Oersted Effect

Often during his lectures at the University of Copenhagen H. C. Oersted had demonstrated the non-existence of a connection between electricity and magnetism. He would place a compass needle near to and at right angles to a current carrying wire to show that there was no effect of one on the other. After one of the lectures a student asked, "but, Professor Oersted, what would happen if the compass needle was placed parallel to the current carrying wire?" Oersted said, "Well, let's see," and went down in the history of physics; the student's name is forgotten.

(Adapted from H.E. White, Modern College Physics, pp 433, D. Van Nostrand, Princeton, 1962)