Page:Scientific Memoirs, Vol. 1 (1837).djvu/546

534 of substituting for the cylindrical form the ordinary U form of electro-magnetic bars, and of augmenting within certain limits the number and magnitude of these pieces, as well as the length of the spirals. But not having arrived at the termination of my experiments on this subject, I confine myself for the present to pointing out the above-mentioned facts, which I have thought proper to make known, not only as interesting to science, but also because the study of the new class of effects with which it is connected may be considered as fertile in useful consequences in a physico-mechanical point of view.

 

electro-magnetism from its intrinsic importance certainly is one of the most remarkable and interesting discoveries of modern times, yet it would create a much higher interest, and gain in popularity, if it could be rendered practically useful. For some time past I had been occupied with the idea, whether the power of electro-magnets, which without doubt might be infinitely increased, could be applied as a motive power for machinery. It was known from Van Moll's experiments, that when the electric current which runs through the spiral of an electro-magnet is rapidly reversed, the magnetic poles are likewise instantly reversed; and that a light iron keeper, which is supported from its poles, falls off at that moment, but is immediately re-attracted. The experiments of Henry and Ten Eyck showed that the power of such electro-magnets might be very greatly augmented. The thought struck me, that a considerably heavier keeper or armature might be suspended from such an electro-magnet, and that by the attraction and repulsion of the same a machine might be put in motion; at the same time the action of the gyrotrope, and thereby the reversion of the poles, might also be effected: and although the distance which the keeper would recede from the magnet could be but very inconsiderable, still I thought that the rapidity with which these motions would follow each other might in great measure compensate for this defect. I was, however, 