534: DR. SCITULTHESS ON THE APPLICATION OF 
of substituting for the cylindrical form the ordinary U form of eleetro- 
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-men- 
tioned 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*. 
Part of a Lecture on Electro-Magnetism, delivered to the 
Philosophical Society at Zurich, February the 18th, 1833 ; 
by the late Dr. R. ScHuttuEss t+. 
From a work intitled ‘“‘ Ueber Electromagnetismus, nebst Angabe einer neuen 
durch electromagnetische Kriifte bewegten Maschine: Drey Vorlesungen 
von Dr. R. Schulthess. Zurich, 1835.” 
Tuoucu 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 popula- 
rity, 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 experi- 
ments, 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, 
* The apparatus mentioned in this Note was constructed by M. Jast, me- 
chanician of the Royal University of Turin, who executes with the same success 
and the same accuracy ail other kinds of philosophical instruments. 
+ The translation has been communicated by E, Solly, jun., Esq. 
