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

By Benjamin Franklin

Page 222

propose, the sparks
would not only be near strait _in vacuo_, but strike at a greater
distance than in the open air, though perhaps there would not be a
loud explosion. As soon as I have a little leisure, I will make the
experiment, and send you the result.

My supposition, that the sea might possibly be the grand source
of lightning, arose from the common observation of its luminous
appearance in the night, on the least motion; an appearance never
observed in fresh water. Then I knew that the electric fluid may be
pumped up out of the earth, by the friction of a glass globe, on
a non-electric cushion; and that, notwithstanding the surprising
activity and swiftness of that fluid, and the non-electric
communication between all parts of the cushion and the earth, yet
quantities would be snatched up by the revolving surface of the
globe, thrown on the prime conductor, and dissipated in air. How
this was done, and why that subtle active spirit did not immediately
return again from the globe, into some part or other of the cushion,
and so into the earth, was difficult to conceive; but whether from
its being opposed by a current setting upwards to the cushion, or
from whatever other cause, that it did not so return was an evident
fact. Then I considered the separate particles of water as so many
hard spherules, capable of touching the salt only in points, and
imagined a particle of salt could therefore no more be wet by a
particle of water, than a globe by a cushion; that there might
therefore be such a friction between these originally constituent
particles of salt and water, as in a sea of globes and cushions; that
each particle of water on the surface might obtain from the common
mass, some particles of the universally diffused, much finer, and
more subtle electric fluid, and forming to itself an atmosphere of
those particles, be repelled from the then generally electrified
surface of the sea, and fly away with them into the air. I thought
too, that possibly the great mixture of particles electric _per se_,
in the ocean water, might, in some degree, impede the swift motion
and dissipation of the electric fluid, through it to the shores,
&c.--But having since found, that salt in the water of an electric
phial does not lessen the shock; and having endeavoured in vain to
produce that luminous appearance from a mixture of salt and water
agitated; and observed, that even the sea-water will not produce it
after some hours standing in a bottle; I suspect it to

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Text Comparison with Experiments and Observations on Electricity Made at Philadelphia in America

Page 0
* * * * * EXPERIMENTS AND OBSERVATIONS ON ELECTRICITY, MADE AT _Philadelphia_ in _America_, BY Mr.
Page 1
_ _It has, indeed, been of late the fashion to ascribe every grand or unusual operation of nature, such as lightening and earthquakes, to electricity; not, as one would imagine, from the manner of reasoning on these occasions, that the authors of these schemes have, discovered any connection betwixt the cause and effect, or saw in what manner they were related; but, as it would seem, merely because they were unacquainted with any other agent, of which it could not positively be said the connection was impossible.
Page 2
At the same time that the wire and top of the bottle, &c.
Page 6
LETTER II.
Page 10
_ We suppose it was _driven off_, and not brought on thro' that wire; and that the machine and man, _&c.
Page 11
We rub our tubes with buckskin, and observe always to keep the same side to the tube, and never to sully the tube by handling; thus they work readily and easily, without the least fatigue; especially if kept in tight pastboard cases, lined with flannel, and fitting closeto the tube.
Page 13
11.
Page 15
--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 a 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 16
for the reason given s 10.
Page 18
it, did not seem in the least to retard its motion.
Page 20
A dry cake of ice, or an icicle held between two in a circle, likewise prevents the shock; which one would not expect, as water conducts it so perfectly well.
Page 21
_April 29, 1749.
Page 26
But if two gun-barrels electrified will strike at two inches distance, and make a loud snap, to what a great distance may 10,000 acres of electrified cloud strike and give its fire, and how loud must be that crack! 38.
Page 27
When it passes thro' dense bodies 'tis unseen.
Page 35
The following experiments, as well as those in my first paper, show this power.
Page 36
As they move round, you see that scale draw nigher to the floor, and dip more when it comes over the punch; and if that be placed at a proper distance, the scale will snap and discharge its fire into it.
Page 41
You may make this figure so acute below and blunt above, as to need no under plate, it discharging fast enough into the air.
Page 45
As this charg'd part of the globe comes round to the cushion again, the outer surface delivers its overplus fire into the cushion, the opposite inner surface receiving at the same time an equal quantity from the.
Page 51
Page 40, sect.
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IV.