Expériences et observations sur l'électricité faites à Philadelphie en Amérique

By Benjamin Franklin

Page 134

état négatif
d'électricité par rapport à la terre selon la plûpart de nos
expériences; cependant comme dans l'une nous avons trouvé un nuage
électrisé positivement, je conjecture que dans ce cas un pareil nuage,
après avoir reçu ce qui, dans son état de raréfaction, étoit seulement
sa quantité naturelle se trouva comprimé par l'action des vents ou de
quelqu'autre manière, ensorte qu'une partie de ce qu'il avoit absorbé,
fut chassée, & forma une atmosphère électrique autour de lui dans son
état de condensation. C'est ce qui le rendit capable de communiquer une
électricité positive à la verge.

Pour prouver qu'un corps dans différentes circonstances de dilatation &
de contraction est capable de recevoir & de retenir plus ou moins de
fluide électrique sur sa surface, je rapporterai l'expérience suivante:
Je plaçai sur le plancher un verre à boire propre, & dessus un petit pot
d'argent, dans lequel je mis environ trois brasses de chaîne de cuivre,
à un bout de laquelle j'attachai un fil de soye qui s'élevoit
directement au plat-fond où il passoit sur une poulie & delà
redescendoit dans ma main, de sorte que je pouvois à mon gré enlever la
chaîne du pot, l'élever à un pied de distance du plat-fond & la laisser
par gradation retomber dans le pot.

Du plat-fond avec un autre fil de fine soye écruë, je suspendis un petit
floccon de coton, de manière que quand il pendoit perpendiculairement il
touchoit le côté du pot: ensuite approchant du pot le crochet d'une
bouteille chargée, je lui donnai une étincelle qui se répandit autour en
atmosphère électrique, & le floccon de coton fut repoussé du côté du pot
à la distance de neuf ou dix pouces: le pot ne recevoit plus alors
d'autre étincelle du crochet de la bouteille; mais à mesure que
j'élevois la chaîne, l'atmosphère du pot diminua en se coulant sur la
chaîne qui s'élevoit, & en conséquence le floccon de coton s'approcha de
plus en plus du pot; & alors si je rapprochois de ce pot le crochet de
la bouteille, il recevoit une autre étincelle & le coton retournoit à la
même distance qu'auparavant, & de cette sorte à proportion que la chaîne
étoit élevée plus haut, le pot recevoit plus d'étincelles, parce que le
pot avec la chaîne déployée étoit capable de supporter une plus grande
atmosphère que le pot avec la chaîne ramassée dans son intérieur. Que
l'atmosphère autour du pot fût diminuée en enlevant la chaîne, &
augmentée en la baissant, c'est une chose non-seulement conforme à la
raison, puisque l'atmosphère de la chaîne doit être tirée de celle du
pot quand elle

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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 8
I continued, however, at the grammar-school rather less than a year, though in that time I had risen gradually from the middle of the class of that year to be at the head of the same class, and was removed into the next class, whence I was to be placed in the third at the end of the year.
Page 22
At his house I lay that night, and arrived the next morning at Burlington, but had the mortification to find that the regular boats had gone a little before, and no other expected to go before Tuesday, this being Saturday.
Page 54
I composed a sheet a day, and Meredith worked it off at press; it was often eleven at night, and sometimes later, before I had finished my distribution for the next day's work, for the little jobs sent in by our other friends now and then.
Page 57
No, said he, my father has really been disappointed, and is really unable; and I am unwilling to distress him farther.
Page 77
My circumstances, however, grew daily easier.
Page 83
Her ways are ways of pleasantness, and all her paths are peace.
Page 85
{ 2} { 3} { 4} I entered upon the execution of this plan for self-examination, and continued it, with occasional intermissions, for some time.
Page 115
This sum may be soon spent, the regret only remaining of having foolishly consumed it: but, in the other case, he escapes the frequent vexation of waiting for barbers, and of their sometimes dirty fingers, offensive breaths, and dull razors: he shaves when most convenient to him, and enjoys daily the pleasure of its being done with a good instrument.
Page 131
We had one swivel gun, which we mounted on one of the angles, and fired it as soon as fixed, to let the Indians know, if any were within hearing, that we had such pieces; and thus our fort (if that name may be given to so miserable a stockade) was finished in a week, though it rained so hard every other day that the men could not well work.
Page 139
On this he did not then explain himself; but when he afterward came to do business with the Assembly, they appeared again; the disputes were renewed, and I was as active as ever in the opposition, being the penman, first of the request to have a communication of the instructions, and then of the remarks upon them, which may be found in the Votes of the Times, and in the HISTORICAL REVIEW I afterward published: but between us personally no enmity arose; we were often together; he was a man of letters, and had seen much of the world, and was entertaining and pleasing in conversation.
Page 150
In the year 1749, he first suggested his idea of explaining the phenomena of thunder-gusts, and of the aurora borealis, upon electrical principles.
Page 153
Grey, while the science was in its infancy.
Page 163
of inflexibility scarcely paralleled.
Page 169
Smith, provost of the college of Philadelphia, and David Rittenhouse, one of its members, were selected by the Philosophical Society to prepare a eulogium to the memory of its founder; and the subscribers to the City Library, who had just erected a handsome building for containing their books, left a vacant niche for a statue of their benefactor.
Page 189
They will not find a rebellion: they may indeed make one.
Page 195
It was not till after his defeat that the colonies were attacked.
Page 201
He is said to have been an exceeding good man, considering his education, being naturally of a most kind, benevolent temper.
Page 210
This man is my friend, my house is his fort, and I am his soldier.
Page 214
One hundred and forty peaceable Indians yet remain in this government.
Page 216
A father and his family, the latter united by interest and affection, the former to be revered for the wisdom of his institutions and the indulgent use of his authority, was the form it was at first presented in.