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

By Benjamin Franklin

Page 260

if the barrel
were kept under water. This tin-foil is but about eighteen pence
sterling a pound, and is so extremely thin, that I imagine a pound of
it would line three or four powder-barrels.

I am, &c.

B. FRANKLIN.

FOOTNOTE:

[80] Peter Franklin. _Editor._




_Of Lightning, and the Methods (now used in America) of securing
Buildings and Persons from its mischievous Effects._


Experiments made in electricity first gave philosophers a suspicion,
that the matter of lightning was the same with the electric matter.
Experiments afterwards made on lightning obtained from the clouds by
pointed rods, received into bottles, and subjected to every trial,
have since proved this suspicion to be perfectly well founded;
and that whatever properties we find in electricity, are also the
properties of lightning.

This matter of lightning, or of electricity, is an extreme subtile
fluid, penetrating other bodies, and subsisting in them, equally
diffused.

When by any operation of art or nature, there happens to be a greater
proportion of this fluid in one body than in another, the body
which has most will communicate to that which has least, till the
proportion becomes equal; provided the distance between them be not
too great; or, if it is too great, till there be proper conductors to
convey it from one to the other.

If the communication be through the air without any conductor, a
bright light is seen between the bodies, and a sound is heard. In
our small experiments, we call this light and sound the electric
spark and snap; but in the great operations of nature, the light is
what we call _lightning_, and the sound (produced at the same time,
though generally arriving later at our ears than the light does to
our eyes) is, with its echoes, called _thunder_.

If the communication of this fluid is by a conductor, it may be
without either light or sound, the subtle fluid passing in the
substance of the conductor.

If the conductor be good and of sufficient bigness, the fluid passes
through it without hurting it. If otherwise, it is damaged or
destroyed.

All metals, and water, are good conductors.--Other bodies may become
conductors by having some quantity of water in them, as wood, and
other materials used in building, but not having much water in them,
they are not good conductors, and therefore are often damaged in the
operation.

Glass, wax, silk, wool, hair, feathers, and even wood, perfectly dry
are non-conductors: that is, they resist instead of facilitating the
passage of this subtle fluid.

When this fluid has an opportunity of passing through two conductors,
one good, and sufficient, as of

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

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Page 127
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Page 243
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mysterious art_, twice repeated; _magic charms can ne'er relieve you_, three times.
Page 290
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Page 308
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Page 356
_British empire_, an union of several states, iii.
Page 364
shock, observations on, 182.