Joseph Henry's Contributions to the Electromagnet and the Electric Motor

Henry discovered that if a cell of a single pair of electrodes is to be used with a given magnet, the magnet should be wound with several coils of wire in parallel; on the other hand, if a battery of many cells is to be used, the magnet winding should form a single long wire. Henry was the first person to understand this idea. It later became a fundamental basis for much of electrical technology, and, in particular, made Samuel F. B. Morse's telegraph feasible.

Applying this principle (together with the valuable but less easily described practical skill in magnet-making he had acquired in the course of his experiments), Henry, with the assistance of a colleague, Philip Ten Eyck, went on to build a 21-pound "experimental magnet on a large scale." With a modest battery, this "Albany magnet" supported 750 pounds, making it, Henry claimed, "probably, therefore, the most powerful magnet ever constructed.


No comments:

Post a Comment