Faraday knew of all the discussions which had arisen respecting Arago’s rotations. They may have been the cause of his unsuccessful attempts of 1824 and 1825. In April, 1828, for the fourth time he tried to discover the currents which he was convinced must be producible by the magnet, and for the fourth time without result. The cause of failure was that both magnet and coil were at rest. [Illustration: FIG. 4.] The summer of 1831 witnessed him for the fifth time making the attack on the problem thus persistently before him. In his laboratory note-book he heads the research “Experiments on the production of electricity from magnetism.” The following excellent summary of the laboratory notes is taken from Bence Jones’s “Life and Letters”:-- I have had an iron ring made (soft iron), iron round and ⅞ths of an inch thick, and ring six inches in external diameter. Wound many coils of copper round, one half of the coils being separated by twine and calico; there were three lengths of wire, each about twenty-four feet long, and they could be connected as one length, or used as separate lengths. By trials with a trough each was insulated from the other. Will call this side of the ring A. On the other side, but separated by an interval, was wound wire in two pieces, together amounting to about sixty feet in length, the direction being as with the former coils. This side call B.[22] Charged a battery of ten pairs of plates four inches square. Made the coil on B side one coil, and connected its extremities by a copper wire passing to a distance, and just over a magnetic needle (three feet from wire ring), then connected the ends of one of the pieces on A side with battery: immediately a sensible effect on needle. It oscillated and settled at last in original position. On breaking connection of A side with battery, again a disturbance of the needle. [Sidenote: SUCCESS IN SIGHT.] In the seventeenth paragraph, written on the 30th of August, he says, “May not these transient effects be connected with causes of difference between power of metals at rest and in motion in Arago’s experiments?” After this he prepared fresh apparatus. As was his manner, he wrote off to one of his friends a letter telling what he was at work upon. On this occasion the recipient of his confidences was his friend Phillips:-- [_Michael Faraday to Richard Phillips._] Royal Institution. Sept. 23, 1831. MY DEAR PHILLIPS,