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at once experimenting with
electricity. In Watson's book were given directions for making
various experiments, and these assisted Franklin in repeating the old
experiments, and eventually adding new ones. Associated with Franklin,
and equally interested and enthusiastic, if not equally successful in
making discoveries, were three other men, Thomas Hopkinson, Philip Sing,
and Ebenezer Kinnersley. These men worked together constantly, although
it appears to have been Franklin who made independently the important
discoveries, and formulated the famous Franklinian theory.
Working steadily, and keeping constantly in touch with the progress of
the European investigators, Franklin soon made some experiments which
he thought demonstrated some hitherto unknown phases of electrical
manifestation. This was the effect of pointed bodies "in DRAWING OFF
and THROWING OFF the electrical fire." In his description of this
phenomenon, Franklin writes:
"Place an iron shot of three or four inches diameter on the mouth of a
clean, dry, glass bottle. By a fine silken thread from the ceiling
right over the mouth of the bottle, suspend a small cork ball, about the
bigness of a marble; the thread of such a length that the cork ball may
rest against the side of the shot. Electrify the shot, and the ball
will be repelled to the distance of four or five inches, more or less,
according to the quantity of electricity. When in this state, if you
present to the shot the point of a long, slender shaft-bodkin, at six
or eight inches distance, the repellency is instantly destroyed, and the
cork flies to the shot. A blunt body must be brought within an inch, and
draw a spark, to produce the same effect.
"To prove that the electrical fire is DRAWN OFF by the point, if you
take the blade of the bodkin out of the wooden handle and fix it in a
stick of sealing-wax, and then present it at the distance aforesaid,
or if you bring it very near, no such effect follows; but sliding one
finger along the wax till you touch the blade, and the ball flies to
the shot immediately. If you present the point in the dark you will see,
sometimes at a foot distance, and more, a light gather upon it like that
of a fire-fly or glow-worm; the less sharp the point, the nearer you
must bring it to observe the light; and at whatever distance you see the
light, you may draw off the electrical fire and destroy the repellency.
If a cork ball so suspended be repelled by the tube, a
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