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nd a point
be presented quick to it, though at a considerable distance, 'tis
surprising to see how suddenly it flies back to the tube. Points of
wood will do as well as those of iron, provided the wood is not dry; for
perfectly dry wood will no more conduct electricity than sealing-wax.
"To show that points will THROW OFF as well as DRAW OFF the electrical
fire, lay a long, sharp needle upon the shot, and you cannot electrify
the shot so as to make it repel the cork ball. Or fix a needle to the
end of a suspended gun-barrel or iron rod, so as to point beyond it
like a little bayonet, and while it remains there, the gun-barrel or rod
cannot, by applying the tube to the other end, be electrified so as to
give a spark, the fire continually running out silently at the point. In
the dark you may see it make the same appearance as it does in the case
before mentioned."(3)
Von Guericke, Hauksbee, and Gray had noticed that pointed bodies
attracted electricity in a peculiar manner, but this demonstration
of the "drawing off" of "electrical fire" was original with Franklin.
Original also was the theory that he now suggested, which had at least
the merit of being thinkable even by non-philosophical minds. It assumes
that electricity is like a fluid, that will flow along conductors and
accumulate in proper receptacles, very much as ordinary fluids do. This
conception is probably entirely incorrect, but nevertheless it is likely
to remain a popular one, at least outside of scientific circles, or
until something equally tangible is substituted.
FRANKLIN'S THEORY OF ELECTRICITY
According to Franklin's theory, electricity exists in all bodies as a
"common stock," and tends to seek and remain in a state of equilibrium,
just as fluids naturally tend to seek a level. But it may, nevertheless,
be raised or lowered, and this equilibrium be thus disturbed. If a body
has more electricity than its normal amount it is said to be POSITIVELY
electrified; but if it has less, it is NEGATIVELY electrified. An
over-electrified or "plus" body tends to give its surplus stock to
a body containing the normal amount; while the "minus" or
under-electrified body will draw electricity from one containing the
normal amount.
Working along lines suggested by this theory, Franklin attempted to show
that electricity is not created by friction, but simply collected from
its diversified state, the rubbed glass globe attracting a certain
quantity of "el
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