ar forms on
a second board, so that when brought near the first, the wires should
everywhere touch, except that a sheet of thick paper was interposed. One of
these wires was connected with the galvanometer, and the other with a
voltaic battery. The first wire was then moved towards the second, and as
it approached, the needle was deflected. Being then removed, the needle was
deflected in the opposite direction. By first making the wires approach and
then recede, simultaneously with the vibrations of the needle, the latter
soon became very extensive; but when the wires ceased to move from or
towards each other, the galvanometer-needle soon came to its usual
position.

19. As the wires approximated, the induced current was in the _contrary_
direction to the inducing current. As the wires receded, the induced
current was in the _same_ direction as the inducing current. When the wires
remained stationary, there was no induced current (54.).

20. When a small voltaic arrangement was introduced into the circuit
between the galvanometer (10.) and its helix or wire, so as to cause a
permanent deflection of 30 deg. or 40 deg., and then the battery of one hundred
pairs of plates connected with the inducing wire, there was an
instantaneous action as before (11.); but the galvanometer-needle
immediately resumed and retained its place unaltered, notwithstanding the
continued contact of the inducing wire with the trough: such was the case
in whichever way the contacts were made (33.).

21. Hence it would appear that collateral currents, either in the same or
in opposite directions, exert no permanent inducing power on each other,
affecting their quantity or tension.

22. I could obtain no evidence by the tongue, by spark, or by heating fine
wire or charcoal, of the electricity passing through the wire under
induction; neither could I obtain any chemical effects, though the contacts
with metallic and other solutions were made and broken alternately with
those of the battery, so that the second effect of induction should not
oppose or neutralise the first (13. 16.).

23. This deficiency of effect is not because the induced current of
electricity cannot pass fluids, but probably because of its brief duration
and feeble intensity; for on introducing two large copper plates into the
circuit on the induced side (20.), the plates being immersed in brine, but
prevented from touching each other by an interposed cloth, the effect at
the i