Experiments and Observations on Electricity Made at Philadelphia in America

By Benjamin Franklin

Page 8

a wood fire; and the light of red-hot iron do
it likewise; but not at so great a distance. Smoke from dry rosin dropt on
hot iron, does not destroy the repellency; but is attracted by both shot
and cork-ball, forming proportionable atmospheres round them, making them
look beautifully, somewhat like some of the figures in _Burnet_'s or
_Whiston_'s theory of the earth.

_N. B._ This experiment should be made in a closet where the air is very
still.

The light of the sun thrown strongly on both cork and shot by a
looking-glass for a long time together, does not impair the repellency in
the least. This difference between fire-light and sun-light, is another
thing that seems new and extraordinary to us.

We had for some time been of opinion, that the electrical fire was not
created by friction, but collected, being really an element diffus'd among,
and attracted by other matter, particularly by water and metals. We had
even discovered and demonstrated its afflux to the electrical sphere, as
well as its efflux, by means of little light windmill wheels made of stiff
paper vanes, fixed obliquely and turning freely on fine wire axes. Also by
little wheels of the same matter, but formed like water wheels. Of the
disposition and application of which wheels, and the various phaenomena
resulting, I could, if I had time, fill you a sheet. The impossibility of
electrising one's self (tho' standing on wax) by rubbing the tube and
drawing the fire from it; and the manner of doing it by passing the tube
near a person or thing standing on the floor, &c. had also occurred to us
some months before Mr _Watson_'s ingenious _Sequel_ came to hand, and these
were some of the new things I intended to have communicated to you.--But
now I need only mention some particulars not hinted in that piece, with our
reasonings thereupon; though perhaps the latter might well enough be
spared.

1. A person standing on wax, and rubbing the tube, and another person on
wax drawing the fire; they will both of them, (provided they do not stand
so as to touch one another) appear to be electrised, to a person standing
on the floor; that is, he will perceive a spark on approaching each of them
with his knuckle.

2. But if the persons on wax touch one another during the exciting of the
tube, neither of them will appear to be electrised.

3. If they touch one another after exciting the tube, and drawing the fire
as aforesaid, there will be a stronger spark between them, than was

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Text Comparison with Experiments and Observations on Electricity Made at Philadelphia in America

Page 1
Animals are in an Instant struck breathless, bodies almost impervious by any force yet known, are perforated, and metals fused by it, in a moment.
Page 4
FIG.
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B.
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To take the charg'd phial safely by the hook, and not at the same time diminish its force, it must first be set down on an electric _per se_.
Page 12
Vary the experiment, by charging two phials equally, one thro' the hook, the other thro' the coating: hold that by the coating which was charged thro' the hook; and that by the hook which was charg'd thro' the coating: apply the hook of the first to the coating of the other, and there will be no shock or spark.
Page 13
A phial cannot be charged standing on wax or glass, or hanging on the prime conductor, unless a communication be form'd between its coating and the floor.
Page 14
_ we may take away part of it from one of the sides, provided we throw an equal quantity into the other.
Page 17
On the principle, in s 7, that hooks of bottles, differently charged, will attract and repel differently, is made, an electrical wheel, that turns with considerable strength.
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25.
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Perhaps if that due quantity of electrical fire so obstinately retained by glass, could be separated from it, it would no longer be glass; it might lose its transparency, or its brittleness, or its elasticity.
Page 21
Thus the stream of a fountain, naturally dense and continual, when electrified, will separate and spread in the form of a brush, every drop endeavouring to recede from every other drop.
Page 26
But tho' the light seems to shoot from the north southerly, the progress of the fire is really from the south northerly, its motion beginning in the north being the reason that 'tis there first seen.
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And we know that common matter has not.
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10.
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And this form it takes, because it is attracted by all parts of the surface of the body, tho' it cannot enter the substance already replete.
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Lightning has often been known to strike people blind.
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10 the upper corner.
Page 45
As this charg'd part of the globe comes round to the cushion again, the outer surface delivers its overplus fire into the cushion, the opposite inner surface receiving at the same time an equal quantity from the.
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1st, That a non-electric easily suffers a change in the quantity of the electrical fluid it contains.
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2.