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

By Benjamin Franklin

Page 270

jointly operate on the electric fluid in the point,
opposing its descent, and _aiding the point_ to retain it; contrary
to the repelling power of the prime conductor, which would drive it
down.--And this may also serve to explain the different powers of the
point in the preceding experiment, on the slipping down the finger
and thumb to different distances.

Hence is collected, that a pointed rod erected _between two tall
chimnies_, and very little higher (an instance of which I have seen)
cannot have so good an effect, as if it had been erected on one of
the chimneys, its whole length above it.


EXPERIMENT IV.

If, _instead_ of a long pointed wire, a _large solid body_ (to
represent a building without a point) be brought under and as near
the prime conductor, when charged; the ball of the electrometer will
_fall_ a little; and on taking away the large body, will _rise again_.


OBSERVATION.

Its _rising again_ shows that the prime conductor lost little or
none of its electric charge, as it had done through the point: the
_falling_ of the ball while the large body was under the conductor
therefore shows, that a quantity of its atmosphere was drawn from the
end where the electrometer is placed to the part immediately over the
large body, and there accumulated _ready_ to strike into it with its
whole undiminished force, as soon as within the striking distance;
and, were the prime conductor moveable like a _cloud_, it would
approach the body by attraction till within that distance. The swift
motion of clouds, as driven by the winds, probably prevents this
happening so often as otherwise it might do: for, though parts of
the cloud may stoop towards a building as they pass, in consequence
of such attraction, yet they are carried forward beyond the striking
distance before they could by their descending come within it.


EXPERIMENT V.

Attach a small light _lock of cotton_ to the underside of the
prime conductor, so that it may hang down towards the pointed wire
mentioned in the first experiment. _Cover_ the point with your
finger, and the globe being turned, the cotton will extend itself,
stretching down towards the finger, as at _a_; but on _uncovering_
the point, it instantly flies up to the prime conductor, as at _b_,
and continues there as long as the point is uncovered. The moment
you cover it again, the cotton flies down again, extending itself
towards the finger; and the same happens in degree, if (instead of
the finger) you use, uncovered, the _blunt_ end of the wire uppermost.


OBSERVATION.

To explain this, it is supposed that

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Text Comparison with Benjamin Franklin and the First Balloons

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Williamson, of Grandview-on-the-Hudson, to whom they had come from Vienna.
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A hollow Globe 12 feet Diameter was formed of what is called in England Oiled Silk, here _Taffetas gomme_, the Silk being impregnated with a Solution of Gum elastic in Lintseed Oil, as is said.
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One of 38 feet Diameter is preparing by Mr.
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It is said the Country People who saw it fall were frightned, conceiv'd from its bounding a little, when it touched the Ground, that there was some living Animal in it, and attack'd it with Stones and Knives, so that it was much mangled; but it is now brought to Town and will be repaired.
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It has been even fancied that in time People will keep such Globes anchored in the Air, to which by Pullies they may draw up Game to be preserved in the Cool & Water to be frozen when Ice is wanted.
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Smaller Repetitions of the Experiment are making every day in all quarters.
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_Planant sur l'Horizon.
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One of these courageous Philosophers, the Marquis d'Arlandes, did me the honour to call upon me in the Evening after the Experiment, with Mr.
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We should not suffer Pride to prevent our progress in Science.
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Never before was a philosophical Experiment so magnificently attended.
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The Wind was very little, so that the Object, tho' moving to the Northward, continued long in View; and it was a great while before the admiring People began to disperse.
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Charles voulant profiter du peu de Jour qui lui restoit, pour.
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_ The hand-writing is in a more flowing style than the subsequent letters.
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28th and first printed in the _Journal de Paris_ but was republished by Faujas de Saint-Fond in his second volume.
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2d" corrected to "Sept.