90 
MR. H. WILDE’S EXPERIMENTAL RESEARCHES 
adduced for the purpose of illustrating some analogous phenomena observed in connexion 
with certain combinations of static and dynamic force in molecular mechanics which 
form the subject of the present research, it is not my intention to enter into the ratio- 
nale of either of them, but to direct attention to some new and paradoxical phenomena 
arising out of Faraday’s important discovery of magneto-electric induction, the close 
consideration of which has resulted in the discovery of a means of producing dynamic 
electricity in quantities unattainable by any apparatus hitherto constructed. 
3. If round a piece of iron forming the armature of a permanent magnet a quantity 
of insulated wire be wound at right angles to the line which joins the poles of the 
magnet, and if the free ends of the wire be connected together directly, or indirectly by 
the interposition of some conductor, a momentary wave of electricity, as is well known, 
is generated in the wire every time the armature is suddenly removed from the magnet, 
or suddenly approaches it; and the wave of electricity generated by the removal of the 
armature moves in the opposite direction to that generated by the approach of the 
armature. With a description of this simple experiment, Faraday announced (in 1831) 
the discovery of magneto-electricity*, which was found to possess all the distinguishing 
characteristics of electricity derived from any other source. 
4. The force of a permanent magnet is usually estimated by the weight which is 
required to separate the armature or submagnet from its poles; and if the question 
were asked, for the first time, what relation existed between the sustaining-power of an 
electro-magnet., excited by means of a magneto-electric machine, and the sustaining- 
power of the permanent magnet from which the electricity was derived, it would pro- 
bably be answered, that since the permanent magnet was the primary cause of the 
phenomena, the electro-magnet would possess, at the most, no greater sustaining-power 
than the permanent magnet. This, however, is not the case ; for I have found that an 
indefinitely small amount of magnetism, or of dynamic electricity, is capable of inducing 
an indefinitely large amount of magnetism. And again, that an indefinitely small 
amount of dynamic electricity, or of magnetism, is capable of evolving an indefinitely 
large amount of dynamic electricity. 
5. That Faraday himself stood on the threshhold of this discovery, will be obvious 
from the following observations made by him in a paper “ On the Physical Character 
of the Lines of Magnetic Force” f, in which, when speaking of the magnet as a source 
of electricity, he says, “ Its analogy with the helix is wonderful, nevertheless there is, as 
yet, a striking experimental distinction between them ; for whereas an unchangeable 
magnet can never raise up a piece of soft iron to a state more than equal to its own, as 
measured by the moving wire (3219), a helix carrying a current can develope in an iron 
core magnetic force, of a hundred or more times as much power as that possessed by 
itself, when measured by the same means. In every point of view, therefore, the magnet 
deserves the utmost exertions of the philosopher for the development of its nature, both 
as a magnet and also as a source of electricity, that we may become acquainted with the 
* Philosophical Transactions, 1832, vol. cxxii. f Philosophical Magazine, June 1852, par. 3273. 
