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

By Benjamin Franklin

Page 240

will not be through the glass, but on
the surface, round by the edge of it."

By this last experiment of Mr. Canton's, it appears, that though by
a moderate heat, thin glass becomes, in some degree, a conductor of
electricity, yet, when of the thickness of a common pane, it is not,
though in a state near melting, so good a conductor as to pass the
shock of a discharged bottle. There are other conductors which suffer
the electric fluid to pass through them gradually, and yet will not
conduct a shock. For instance, a quire of paper will conduct through
its whole length, so as to electrify a person, who, standing on wax,
presents the paper to an electrified prime conductor; but it will
not conduct a shock even through its thickness only; hence the shock
either fails, or passes by rending a hole in the paper. Thus a sieve
will pass water gradually, but a stream from a fire engine would
either be stopped by it, or tear a hole through it.

It should seem, that to make glass permeable to the electric fluid,
the heat should be proportioned to the thickness. You found the heat
of boiling water, which is but 210, sufficient to render the extreme
thin glass in a Florence flask permeable even to a shock.--Lord
Charles Cavendish, by a very ingenious experiment, has found the heat
of 400 requisite to render thicker glass permeable to the common
current.

"A glass tube, (See _Plate_ III.) of which the part C B was solid,
had wire thrust in each end, reaching to B and C.

"A small wire was tied on at D, reaching to the floor, in order to
carry off any electricity that might run along upon the tube.

"The bent part was placed in an iron pot, filled with iron filings;
a thermometer was also put into the filings; a lamp was placed under
the pot; and the whole was supported upon glass.

"The wire A being electrified by a machine, before the heat was
applied, the corks at E separated, at first upon the principle of the
Leyden phial.

"But after the part C B of the tube was heated to 600, the corks
continued to separate, though you discharged the electricity by
touching the wire at E, the electrical machine continuing in motion.

"Upon letting the whole cool, the effect remained till the
thermometer was sunk to 400."

[Illustration: (of the experiment above)

_Plate III._ _Vol. I. page 348._
]

It were to be wished, that this noble philosopher would communicate
more

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Text Comparison with Memoirs of Benjamin Franklin; Written by Himself. [Vol. 1 of 2] With His Most Interesting Essays, Letters, and Miscellaneous Writings; Familiar, Moral, Political, Economical, and Philosophical, Selected with Care from All His Published Productions, and Comprising Whatever Is Most Entertaining and Valuable to the General Reader

Page 59
I dressed plain, and was seen at no places of idle diversion: I never went out a fishing or shooting: a book, indeed, sometimes debauched me from my work, but that was seldom, was private, and gave no scandal: and to show that I was not above my business, I sometimes brought home the paper I purchased at the stores through the streets on a wheelbarrow.
Page 60
I was at first apprehensive of a powerful rival in Harry, as his friends were very able, and had a good deal of interest: I therefore proposed a partnership to him, which he, fortunately for me, rejected with scorn.
Page 64
The first that I can give account of is my great grandfather, as it was a custom in those days among young men too many times to goe to seek their fortune, and in his travels he went upon liking to a taylor; but he kept such a stingy house, that he left him and travelled farther, and came to a smith's house, and coming on a fasting day, being in popish times, he did not like there the first day; the next morning the servant was called up at five in the morning, but after a little time came a good toast and good beer, and he found good housekeeping there; he served and learned the trade of a smith.
Page 71
"As no end, likewise, happens without a means, so we shall find, sir, that even you yourself framed a plan by which you became considerable; but, at the same time, we may see that, though the event is flattering, the means are as simple as wisdom could make them; that is, depending upon nature, virtue, thought, and habit.
Page 73
worth all Plutarch's Lives put together.
Page 81
Eat not to dulness: drink not to elevation.
Page 83
" Another from Cicero: O vitae philosophia dux! O virtutum indagatrix et expultrixque vitiorum! Unus dies bene, et ex praeceptis tuis actus, peccanti immortalitati est anteponendus.
Page 94
I then undertook the Italian: an acquaintance, who was also learning it, used often to tempt me to play chess with him: finding this took up too much of the time I had to spare for study, I at length refused to play any more, unless on this condition, that the victor in every game should have a right to impose a task, either of parts of the grammar to be got by heart, or in translations, &c.
Page 103
The women, by subscriptions among themselves, provided silk collours, which they presented to the companies, painted with different devices and mottoes, which I supplied.
Page 105
Robert Grace, one of my early friends, who, having an iron furnace, found the casting of the plates for these stoves a profitable thing, as they were growing in demand.
Page 114
An accidental occurrence had instructed me how much sweeping might be done in a little time; I found at my door in Craven-street one morning a poor woman sweeping my pavement with a birch broom; she appeared very pale and feeble, as just come out of a fit of sickness.
Page 124
"After taking Fort Duquesne," said he, "I am to proceed to Niagara; and having taken that, to Frontenac, if the season will allow time, and I suppose it will; for Duquesne can hardly detain me above three or four days; and then I see nothing that can obstruct my march to Niagara.
Page 136
It was, however, some time before those papers were much taken notice of in England.
Page 137
What gave my book the more sudden and general celebrity, was the success of one of its proposed experiments, made by Messieurs Dalibard and Delor, at Marly, for drawing lightning from the clouds.
Page 150
Collinson, about the year 1745, sent to the Library Company of Philadelphia an account of these experiments, together with a tube, and directions how to use it.
Page 174
Franklin: * * * * * "With regard to my books, those I had in France and those I left in Philadelphia being now assembled together here, and a catalogue made of them, it is my intention to dispose of the same as follows: My 'History of the Academy of Sciences,' in sixty or seventy volumes quarto, I give to the Philosophical Society of Philadelphia, of which I have the honour to be president.
Page 188
_Q.
Page 195
In 1739 they were called upon to assist in the expedition against Carthagena, and they sent three thousand men to join your army.
Page 200
_ Feb.
Page 217
We indeed seem to _feel_ our own want of political wisdom, since we have been running all about in search of it.