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

By Benjamin Franklin

Page 239

might have been expected from a bottle of that size well
charged, some doubt remained whether part had escaped while the neck
was sealing, or had since, by degrees, soaked through the glass. But
an experiment of Mr. Canton's, in which such a bottle was kept under
water a week, without having its electricity in the least impaired,
seems to show, that when the glass is cold, though extremely thin,
the electric fluid is well retained by it. As that ingenious and
accurate experimenter made a discovery, like yours, of the effect
of heat in rendering thin glass permeable by that fluid, it is but
doing him justice to give you his account of it, in his own words,
extracted from his letter to me, in which he communicated it, dated
Oct. 31, 1760, _viz_.

"Having procured some thin glass balls, of about an inch and a
half in diameter, with stems, or tubes, of eight or nine inches in
length, I electrified them, some positively on the inside, and others
negatively, after the manner of charging the Leyden bottle, and
sealed them hermetically. Soon after I applied the naked balls to my
electrometer, and could not discover the least sign of their being
electrical, but holding them, before the fire, at the distance of
six or eight inches, they became strongly electrical in a very short
time, and more so when they were cooling. These balls will, every
time they are heated, give the electrical fluid to, or take it from
other bodies, according to the _plus_ or _minus_ state of it within
them. Heating them frequently, I find will sensibly diminish their
power; but keeping one of them under water a week did not appear
in the least degree to impair it. That which I kept under water,
was charged on the 22d of September last, was several times heated
before it was kept in water, and has been heated frequently since,
and yet it still retains its virtue to a very considerable degree.
The breaking two of my balls accidentally gave me an opportunity of
measuring their thickness, which I found to be between seven and
eight parts in a thousand of an inch.

A down feather, in a thin glass ball, hermetically sealed, will not
be affected by the application of an excited tube, or the wire of a
charged phial, unless the ball be considerably heated; and if a glass
pane be heated till it begins to grow soft, and in that state be held
between the wire of a charged phial, and the discharging wire, the
course of the electrical fluid

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Text Comparison with Franklin's Way to Wealth; or, "Poor Richard Improved"

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Virtue and Innocence, a Poem 1 0 The Economy of Human Life 1 0 Old Friends in a New Dress, or Selections from Esop's Fables, in Verse, 2 parts, plates 2 0 Little Jack Horner, in Verse, plain 1s.
Page 2
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"Diligence is the mother of good luck, and God gives all things to industry.
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Darton, Junr.
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" [Illustration: Published by W.
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For, in another place, he says, "Many have been ruined by buying good pennyworths.
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" [Illustration: Published by W.
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'This doctrine, my friends, is reason and wisdom; but, after all, do not depend too much upon your own industry, and frugality, and prudence, though excellent things; for they may all be blasted without the blessing of Heaven; and therefore, ask that blessing humbly, and be not uncharitable to those that at present seem to want it, but comfort and help them.
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[Illustration: FINIS.