The Complete Works in Philosophy, Politics and Morals of the late Dr. Benjamin Franklin, Vol. 2 [of 3]

By Benjamin Franklin

Page 133

surface; by which means much of the labour is lost. It is true, that
by placing the wheels higher out of the water, this waste labour
will be diminished in a calm, but where a sea runs, the wheels must
unavoidably be often dipt deep in the waves, and the turning of them
thereby rendered very laborious to little purpose.

Among the various means of giving motion to a boat, that of M.
Bernoulli appears one of the most singular, which was to have fixed
in the boat a tube in the form of an L, the upright part to have a
funnel-kind of opening at top, convenient for filling the tube with
water; which, descending and passing through the lower horizontal
part, and issuing in the middle of the stern, but under the surface
of the river, should push the boat forward. There is no doubt that
the force of the descending water would have a considerable effect,
greater in proportion to the height from which it descended; but
then it is to be considered, that every bucket-full pumped or dipped
up into the boat, from its side or through its bottom, must have
its _vis inertiæ_ overcome so as to receive the motion of the boat,
before it can come to give motion by its descent; and that will be a
deduction from the moving power. To remedy this, I would propose the
addition of another such L pipe, and that they should stand back to
back in the boat thus, figure 13, the forward one being worked as a
pump, and sucking in the water at the head of the boat, would draw it
forward while pushed in the same direction by the force at the stern.
And after all it should be calculated whether the labour of pumping
would be less than that of rowing. A fire-engine might possibly in
some cases be applied in this operation with advantage.

Perhaps this labour of raising water might be spared, and the whole
force of a man applied to the moving of a boat by the use of air
instead of water; suppose the boat constructed in this form, figure
14. A, a tube round or square of two feet diameter, in which a piston
may move up and down. The piston to have valves in it, opening
inwards to admit air when the piston rises; and shutting, when it
is forced down by means of the lever B turning on the centre C. The
tube to have a valve D, to open when the piston is forced down, and
let the

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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
--Positive and negative electricity.
Page 64
My arguments perverted some other young persons, particularly Collins and Ralph.
Page 90
Franklin for his opinion, gave rise to that correspondence which terminated about a year afterwards, in erecting the college upon the foundation of the academy, and establishing that gentleman at the head of both, where he still continues, after a period of thirty-six years, to preside with distinguished reputation.
Page 91
_ "SIR, "I received your favour of the 11th instant, with your new[7] piece on _Education_, which I shall carefully peruse, and give you my sentiments of it, as you desire, by next post.
Page 94
He then assembled his old colleagues at his own house, and being chosen their president, all their future meetings were, at his request, held there, till.
Page 134
What is driven out at the tail of the first, serving to charge the second; what is driven out of the second charging the third; and so on.
Page 136
--Which demonstrated the power to reside in glass as glass, and that the non-electrics in contact served only, like the armature of a loadstone, to unite the force of the several parts, and bring them at once to any point desired: it being the property of a non-electric, that the whole body instantly receives or gives what electrical fire is given to or taken from any one of its parts.
Page 145
Page 154
This shape may be rendered visible in a still air, by raising a smoke from dry rosin dropt into a hot tea-spoon under the electrified body, which will be attracted, and spread itself equally on all sides, covering and concealing the body[49].
Page 190
--But now, when I approached the wire of the charged phial to the rod, instead of the usual stream that I expected from the wire to the rod, there was no spark; not even when I brought the wire and the rod to touch; yet the bells continued ringing vigorously, which proved to me, that the rod was then _positively_ electrified, as well as the wire of the phial, and equally so; and, consequently, that the particular cloud then over the rod was in the same positive state.
Page 195
For the bur round the outside of the hole, is the effect of the explosion every way from the centre of the stream, and not an effect of the direction.
Page 199
This experiment may be made with very small brass balls hung by silver wire; and will succeed as well with sealing-wax made electrical, as with glass.
Page 212
The cork was not attracted to the inside of the can as it would have been to the outside, and though it touched the bottom, yet, when drawn out, it was not found to be electrified by that touch, as it would have been by touching the outside.
Page 221
Gawin Knight, inventor of the steel magnets, has wrote largely on that subject, but I have not yet had leisure to peruse his writings with the attention necessary to become master of his doctrine.
Page 245
If at some times the electricity appears to be negative, as that friction is the same, the effect must be from a negative state of the upper air.
Page 261
metal, the other not so good, it passes in the best, and will follow it in any direction.
Page 274
Whatever power there may be in the glass globe to collect the fulminating fluid, and whatever capacity of receiving and accumulating it there may be in the bottle or glass jar; yet neither the accumulation or the discharge ever exceeds the destined quantity.
Page 296
_ 69, "that he can electrise a hundred men, standing on wax, if they hold hands, and if one of them touch one of these surfaces (the exterior) with the end of his finger:" this I know he can, while the phial is charging, but after the phial is charged I am as certain he cannot: that is, hang a phial, prepared for the Leyden experiment, to the conductor, and let a man, standing on the floor, touch the coating with his finger, while the globe is turned, till the electric matter spews out of the hook of the phial, or some part of the conductor, which I take to be the certainest sign that the phial has received all the electric matter it can: after this appears, let the man, who before stood on the floor, step on a cake of wax, where he may stand for hours, and the globe all that time turned; and yet have no appearance of being electrised.
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