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

By Benjamin Franklin

Page 156

farther from C, than any other part of the atmosphere
over the lines C, B, or B, A: and, besides the distance arising
from the nature of the figure, where the attraction is less, the
particles will naturally expand to a greater distance by their mutual
repulsion. On these accounts we suppose electrified bodies discharge
their atmospheres upon unelectrified bodies more easily, and at a
greater distance from their angles and points than from their smooth
sides.--Those points will also discharge into the air, when the
body has too great an electrical atmosphere, without bringing any
non-electric near, to receive what is thrown off: For the air, though
an electric _per se_, yet has always more or less water and other
non-electric matters mixed with it: and these attract and receive
what is so discharged.

17. But points have a property, by which they _draw on_ as well as
_throw off_ the electrical fluid, at greater distances than blunt
bodies can. That is, as the pointed part of an electrified body will
discharge the atmosphere of that body, or communicate it farthest to
another body, so the point of an unelectrified body will draw off
the electrical atmosphere from an electrified body, farther than a
blunter part of the same unelectrified body will do. Thus, a pin
held by the head, and the point presented to an electrified body,
will draw off its atmosphere at a foot distance; where, if the head
were presented instead of the point, no such effect would follow. To
understand this, we may consider, that if a person standing on the
floor would draw off the electrical atmosphere from an electrified
body, an iron crow and a blunt knitting-needle held alternately in
his hand, and presented for that purpose, do not draw with different
forces in proportion to their different masses. For the man, and
what he holds in his hand, be it large or small, are connected with
the common mass of unelectrified matter; and the force with which
he draws is the same in both cases, it consisting in the different
proportion of electricity in the electrified body, and that common
mass. But the force with which the electrified body retains its
atmosphere by attracting it, is proportioned to the surface over
which the particles are placed; _i. e._ four square inches of that
surface retain their atmosphere with four times the force that one
square inch retains its atmosphere. And as in plucking the hairs from
the horse's tail, a degree of strength not sufficient to pull away a
handful at once, could yet easily strip it hair by hair;

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Text Comparison with Benjamin Franklin and the First Balloons

Page 0
In.
Page 1
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.
Page 2
I am much obliged to you for the Care you have taken.
Page 3
They say the filling of it in M.
Page 4
It was dismissed about One aClock in the Morning.
Page 5
The Air rarified.
Page 6
I was then in great Pain for the Men, thinking them in danger of being thrown out, or burnt for I expected that the Balloon being no longer upright the Flame would have laid hold of the inside that leaned over it.
Page 7
_ That is their Provision of Straw; of which they carried up a great Quantity.
Page 8
This Experience is by no means a trifling one.
Page 9
Faujas's Book upon the Balloons, which I hope you have receiv'd.
Page 10
Between One & Two aClock, all Eyes were gratified with seeing it rise majestically from among the Trees, and ascend gradually above the Buildings, a most beautiful Spectacle! When it was about 200 feet high, the brave Adventurers held out and wav'd a little white Pennant, on both Sides their Car, to salute the Spectators, who return'd loud Claps of Applause.
Page 11
I am reliev'd from my Anxiety, by hearing that the Adventurers descended well near l'Isle Adam, before Sunset.
Page 12
Il avoit perdu son air inflammable par le Robinet qu'on avoit laisse ouvert expres pour empecher l'explosion a trop grande hauteur.
Page 13
As this interesting document has never been published, to my knowledge, I have given it here _literatim_ from my press-copy.
Page 14
2^d", for 2nd.