Voltaic Induction. 33 
also well known that when the metal in which the induction takes place, 
is made to move to and from the magnet, opposite voltaic currents, 
result; the cause of which, admitting the hypothesis, will be appa- 
rent. For it is obvious that the magnetic forces Nx, Na’, Nx” do 
not act in parallel lines, but diverge from the point N, of the mag- 
net; and whether we attribute this want of parallelism, to a repul- 
sion among themselves, to an attraction towards the opposite poles 
of the instrument, or, which is most probable, to the curvature that 
characterizes their action as they issue from the polar surface, and 
which is exhibited more intelligibly by the electro-dynamie cylinder, 
still it will follow that the particles, placed between them, must be 
more influenced by those forces intercepted than by those upon the 
opposite sides, and from which they arereceding. Accordingly, the 
outer forces Na, Ne” will effect induction during the motion towards 
the magnet and the inner ones duriag the retreat. The difference 
between the four movemeats will be apparent from an inspection of 
the figure. All particles in their motion downwards will have a simi- 
larity of magnetic rotation, which also will happen when they are 
moved upwards; but the direction in the last case will be the reverse 
of the former. When, however, we suppose the motion to be to or 
from the magnet, counter currents will arise on opposite sides of the 
magnetic axis SN, all the particles, above it, acquiring one kind of 
rotation, and all those below it, the opposite. 
Viewed in relation to single particles, the difference of induction, 
here supposed to result from motion, upon opposite sides, may ap- 
pear to be very inconsiderable ; but it must be remembered that the 
portions of matter, simultaneously influenced, are infinitely numerous 
and are exposed, almost in the same instant of time, to an infinity of 
forces acting in uniformity with each other. ‘The disproportion is, 
perhaps, not much greater, (for infinity limits both,) than that which 
exists between an atom and the universe. But it is freely admitted 
that all this reasoning should have no weight attached to it, unless 
fully supported by experiment; I shall, therefore, proceed to deter- 
mine the direction of the voltaic currents corresponding with these 
circles of magnetic rotation and show that the hypothetical deduction 
is in full accordance with their actual existence. This point being 
satisfactorily established, the conclusion urges itself irresistibly, that 
all voltaic currents, arising from the influence of a magnet or elec- 
tro-dynamic cylinder, are caused by the ordinary process of magnet- 
ic induction, remotely and immediately by the order of rotation. 
Vout. XXVI.—No. 1. 5 
