ordinary magnetic needle so that it is
parallel to it. The magnetic needle will be set in motion and will
deviate towards the west under that part of the conductor which comes
from the negative pole of the galvanic battery. If the wire is not more
than four-fifths of an inch distant from the middle of this needle, this
deviation will be about forty-five degrees. At a greater distance
the angle of deviation becomes less. Moreover, the deviation varies
according to the strength of the battery. The conductor can be moved
towards the east or west, so long as it remains parallel to the needle,
without producing any other result than to make the deviation smaller.

"The conductor can consist of several combined wires or metal coils. The
nature of the metal does not alter the result except, perhaps, to make
it greater or less. We have used wires of platinum, gold, silver, brass,
and iron, and coils of lead, tin, and quicksilver with the same result.
If the conductor is interrupted by water, all effect is not cut off,
unless the stretch of water is several inches long.

"The conductor works on the magnetic needle through glass, metals, wood,
water, and resin, through clay vessels and through stone, for when we
placed a glass plate, a metal plate, or a board between the conductor
and the needle the effect was not cut off; even the three together
seemed hardly to weaken the effect, and the same was the case with an
earthen vessel, even when it was full of water. Our experiments also
demonstrated that the said effects were not altered when we used a
magnetic needle which was in a brass case full of water.

"When the conductor is placed in a horizontal plane under the magnetic
needle all the effects we have described take place in precisely the
same way, but in the opposite direction to what took place when the
conductor was in a horizontal plane above the needle.

"If the conductor is moved in a horizontal plane so that it gradually
makes ever-increasing angles with the magnetic meridian, the deviation
of the magnetic needle from the magnetic meridian is increased when the
wire is turned towards the place of the needle; it decreases, on the
other hand, when it is turned away from that place.

"A needle of brass which is hung in the same way as the magnetic needle
is not set in motion by the influence of the conductor. A needle of
glass or rubber likewise remains static under similar experiments. Hence
the electrical conductor