The Complete Works in Philosophy, Politics and Morals of the late Dr. Benjamin Franklin, Vol. 1 [of 3]

By Benjamin Franklin

Page 248

reduced to vapour, is said to occupy 14,000 times
its former space. I have sent a charge through a small glass tube,
that has borne it well while empty, but when filled first with water,
was shattered to pieces and driven all about the room:--Finding no
part of the water on the table, I suspected it to have been reduced
to vapour; and was confirmed in that suspicion afterwards, when I
had filled a like piece of tube with ink, and laid it on a sheet of
clean paper, whereon, after the explosion, I could find neither any
moisture nor any sully from the ink. This experiment of the explosion
of water, which I believe was first made by that most ingenious
electrician, father Beccaria, may account for what we sometimes
see in a tree struck by lightning, when part of it is reduced to
fine splinters like a broom; the sap vessels being so many tubes
containing a watry fluid, which, when reduced to vapour, rends every
tube lengthways. And perhaps it is this rarefaction of the fluids in
animal bodies killed by lightning or electricity, that, by separating
its fibres, renders the flesh so tender, and apt so much sooner to
putrify. I think too, that much of the damage done by lightning to
stone and brick-walls may sometimes be owing to the explosion of
water, found, during showers, running or lodging in the joints or
small cavities or cracks that happen to be in the walls.

Here are some electricians that recommend knobs instead of points
on the upper end of the rods, from a supposition that the points
invite the stroke. It is true that points draw electricity at greater
distances in the gradual silent way; but knobs will draw at the
greatest distance a stroke. There is an experiment that will settle
this. Take a crooked wire of the thickness of a quill, and of such a
length as that one end of it being applied to the lower part of a
charged bottle, the upper may be brought near the ball on the top of
the wire that is in the bottle. Let one end of this wire be furnished
with a knob, and the other may be gradually tapered to a fine point.
When the point is presented to discharge the bottle, it must be
brought much nearer before it will receive the stroke, than the
knob requires to be. Points besides tend to repel the fragments of
an electrised cloud, knobs draw them nearer. An experiment, which I
believe I have shewn you, of cotton fleece hanging

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Text Comparison with Benjamin Franklin and the First Balloons

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Benjamin Franklin and the First Balloons BY ABBOTT LAWRENCE ROTCH Reprinted from the Proceedings of the American Antiquarian Society Volume XVIII WORCESTER, MASSACHUSETTS THE DAVIS PRESS 1907 BENJAMIN FRANKLIN AND THE FIRST BALLOONS.
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It is supposed that not less than 50,000 People were assembled to see the Experiment.
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Please to accept and present my Thanks.
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The Air rarified.
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There was a vast Concourse of Gentry in the Garden, who had great Pleasure in seeing the Adventurers go off so chearfully, & applauded them by clapping &c.
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They say they have a contrivance which will enable them to descend at Pleasure.
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We should not suffer Pride to prevent our progress in Science.
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30, 1783 Dear Sir, I did myself the honour of writing to you the Beginning of last Week, and I sent you by the Courier, M.
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Charles, Professor of Experimental Philosophy, & a zealous Promoter of that Science; and one of the Messieurs Robert, the very ingenious Constructors of the Machine.
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_Letter of August 30.
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The plate forming the frontispiece to this volume shows the balloon as seen from Mr.
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