Experiments and Observations on Electricity Made at Philadelphia in America

By Benjamin Franklin

Page 18

it, did not seem in the least to retard its
motion.--This is called an electrical jack; and if a large fowl were
spitted on the upright shaft, it would be carried round before a fire with
a motion fit for roasting.

22. But this wheel, like those driven by wind, water, or weights, moves by
a foreign force, to wit, that of the bottles. The self-moving wheel, though
constructed on the same principles, appears more surprising. 'Tis made of a
thin round plate of window-glass, seventeen inches diameter, well gilt on
both sides, all but two inches next the edge. Two small hemispheres of wood
are then fixed with cement to the middle of the upper and under sides,
centrally opposite, and in each of them a thick strong wire eight or ten
inches long, which together make the axis of the wheel. It turns
horizontally on a point at the lower end of its Axis, which rests on a bit
of brass cemented within a glass salt-celler. The upper end of its axis
passes thro' a hole in a thin brass plate cemented to a long strong piece
of glass, which keeps it six or eight inches distant from any non-electric,
and has a small ball of wax or metal on its top to keep in the fire. In a
circle on the table which supports the wheel, are fixed twelve small
pillars of glass, at about four inches distance, with a thimble on the top
of each. On the edge of the wheel is a small leaden bullet communicating by
a wire with the gilding of the _upper_ surface of the wheel; and about six
inches from it is another bullet communicating in like manner with the
_under_ surface. When the wheel is to be charged by the upper surface, a
communication must be made from the under surface to the table. When it is
well charg'd it begins to move; the bullet nearest to a pillar moves
towards the thimble on that pillar, and passing by electrifies it and then
pushes itself from it; the succeeding bullet, which communicates with the
other surface of the glass, more strongly attracts that thimble on account
of its being before electrified by the other bullet; and thus the wheel
encreases its motion till it comes to such a height as that the resistance
of the air regulates it. It will go half an hour, and make one minute with
another twenty turns in a minute, which is six hundred turns in the whole;
the bullet of the upper surface giving in each

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

Page 3
179 Further experiments confirming the preceding observations.
Page 19
To return.
Page 36
he said, a young man of very promising talents, and that, of consequence, I ought to be encouraged; that there were at Philadelphia none but very ignorant printers, and that if I were to set up for myself, he had no doubt of my success; that, for his own part, he would procure me all the public business, and would render me every other service in his power.
Page 45
He then said, Osborne will never acknowledge the smallest degree of excellence in any production of mine.
Page 54
In a garret of the house there lived, in the most retired manner, a lady seventy years of age, of whom I received the following account from my landlady.
Page 74
Godfrey undertook to negociate our little treaty.
Page 84
The similarity of lightning and electricity is so strong, that we need not be surprised at notice being taken of it, as soon as electrical phenomena became familiar.
Page 94
Franklin and the other trustees were enabled to prosecute their plan, for perfecting the institution, and opening the college upon the large and liberal foundation on which it now stands; for which purpose they obtained their additional charter, dated May 27th, 1755.
Page 126
The non-electric contained in the bottle differs, when electrised, from a non-electric electrised out of the bottle, in this: that the electrical fire.
Page 128
So wonderfully are these two states of electricity, the _plus_ and _minus_, combined and balanced in this miraculous bottle! situated and related to each other in a manner that I can by no means comprehend! If it were possible that a bottle should in one part contain a quantity of air strongly comprest, and in another part a perfect vacuum, we know the equilibrium would be instantly restored _within_.
Page 137
Turn up the glass, and gild the fore side exactly over the back gilding, and when it is dry, cover it, by pasting on the pannel of the picture that hath been cut out, observing to bring the correspondent parts of the border and picture together, by which the picture will appear of a piece, as at first, only part is behind the glass, and part before.
Page 151
F.
Page 178
When the air within the.
Page 225
But the chain itself was destroyed, being partly scattered about in fragments of two or three links.
Page 232
page 336.
Page 233
This experiment, I remember, you proposed to me before you left Philadelphia; but I never tried it till now.
Page 269
--But the finger and thumb being substantial and blunt bodies, though as near the prime conductor, hold up better their _own_ natural quantity against the force of that repulsion; and so, continuing nearly in the natural state, they.
Page 328
iii.
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318.
Page 335
_Rosin_, when fluid, will conduct electricity, i.