nd on both
sides of the place of greatest intensity, but gradually diminished in force
from that place. It appeared to be equally powerful at equal distances from
the place of the magnetic poles, not being affected in that respect by the
direction of the rotation. When the rotation of the disc was reversed, the
direction of the current of electricity was reversed also; but the other
circumstances were not affected.

93. On raising the plate, so that the magnetic poles were entirely hidden
from each other by its intervention, (a. fig. 10,) the same effects were
produced in the same order, and with equal intensity as before. On raising
it still higher, so as to bring the place of the poles to c, still the
effects were produced, and apparently with as much power as at first.

94. When the conductor was held against the edge as if fixed to it, and
with it moved between the poles, even though but for a few degrees, the
galvanometer needle moved and indicated a current of electricity, the same
as that which would have been produced if the wheel had revolved in the
same direction, the conductor remaining stationary.

95. When the galvanometer connexion with the axis was broken, and its wires
made fast to two conductors, both applied to the edge of the copper disc,
then currents of electricity were produced, presenting more complicated
appearances, but in perfect harmony with the above results. Thus, if
applied as in fig. 11, a current of electricity through the galvanometer
was produced; but if their place was a little shifted, as in fig. 12, a
current in the contrary direction resulted; the fact being, that in the
first instance the galvanometer indicated the difference between a strong
current through A and a weak one through B, and in the second, of a weak
current through A and a strong one through B (92.), and therefore produced
opposite deflections.

96. So also when the two conductors were equidistant from the magnetic
poles, as in fig. 13, no current at the galvanometer was perceived,
whichever way the disc was rotated, beyond what was momentarily produced by
irregularity of contact; because equal currents in the same direction
tended to pass into both. But when the two conductors were connected with
one wire, and the axis with the other wire, (fig. 14,) then the
galvanometer showed a current according with the direction of rotation
(91.); both conductors now acting consentaneously, and as a single
conductor did befo