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

By Benjamin Franklin

Page 230

is
founded, may be well enough accounted for without it. Will not cork
balls, electrised negatively, separate as far as when electrised
positively? And may not their separation in both cases be accounted
for upon the same principle, namely, the mutual attraction of the
natural quantity in the air, and that which is denser or rarer in the
cork balls? it being one of the established laws of this fluid, that
quantities of different densities shall mutually attract each other,
in order to restore the equilibrium.

I can see no reason to conclude that the air has not its share of
the common stock of electricity, as well as glass, and perhaps, all
other electrics _per se_. For though the air will admit bodies to
be electrised in it either positively or negatively, and will not
readily carry off the redundancy in the one case, or supply the
deficiency in the other, yet let a person in the negative state,
out of doors in the dark, when the air is dry, hold, with his arm
extended, a long sharp needle, pointing upwards, and he will soon
be convinced that electricity may be drawn out of the air; not
very plentifully, for, being a bad conductor, it seems loth to part
with it, but yet some will evidently be collected. The air near the
person's body, having less than its natural quantity, will have
none to spare; but, his arm being extended, as above, some will be
collected from the remoter air, and will appear luminous, as it
converges to the point of the needle.

Let a person electrised negatively present the point of a needle,
horizontally, to a cork ball, suspended by silk, and the ball will be
attracted towards the point, till it has parted with so much of its
natural quantity of electricity as to be in the negative state in the
same degree with the person who holds the needle; then it will recede
from the point, being, as I suppose, attracted the contrary way by
the electricity of greater density in the air behind it. But, as this
opinion seems to deviate from electrical orthodoxy, I should be glad
to see these phenomena better accounted for by your superior and more
penetrating genius.

Whether the electricity in the air, in clear dry weather, be of the
same density at the height of two or three hundred yards, as near
the surface of the earth, may be satisfactorily determined by your
old experiment of the kite. The twine should have throughout a very
small wire in it, and the ends of the wire, where the

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Text Comparison with Benjamin Franklin and the First Balloons

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M.
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And presently the Globe was seen to rise, and that as fast as a Body of 12 feet Diameter, with a force only of 39 Pounds, could be suppos'd to move the resisting Air out of its Way.
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S.
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He was complimented on his Zeal and Courage for the Promotion of Science, but advis'd to wait till the management of these Balls was made by Experience more certain & safe.
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F.
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FRANKLIN SIR JOSEPH BANKS, Bar^t.
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Multitudes in Paris saw the Balloon passing; but did not know there were Men with it, it being then.
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Robert, two Brothers, very ingenious Men, who have made it in concert with Mr.
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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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I shall inclose one of the Tickets of Admission, on which the Globe was represented, as originally intended, but.
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is altered by the Pen to show its real State when it went off.
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Il avoit perdu son air inflammable par le Robinet qu'on avoit laisse ouvert expres pour empecher l'explosion a trop grande hauteur.
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" Since Franklin's copy of the _Proces-Verbal_ differs only in his spelling the word "_sang-froid_" instead of "_sens-froid_," I do not print it.
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2d" corrected to "Sept.