About forty members of the Electric Club of the Institute of Technology, besides a number of Harvard students listened to Professor Trowbridge's lecture in the Physical Laboratory last evening on Magnetism.

Before the time of Farady there were two theories in electricity. The one that it was caused by molecular motion. The other that it was caused by a wave motion similar in many ways to the waves of light and sound. Both of these theories, though apparently so different, may be satisfactorily explained.

A great amount of work has been done in recent years in trying to find new effects of light on magnetism and if possible to show a similarity between them, but on the whole these experiments have not been successful.

In the course of the lecture several very delicate and interesting experiments were performed with alternating currents; among others was the experiment showing the magnetic effect produced by alternating currents on iron filings.

In closing Professor Trowbridge invited the members of the club to look about the laboratory, calling especial attention to the rooms for more advanced work in light and electricity in the west end of the building.