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

By Benjamin Franklin

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peut mettre en leur place les termes _conducteurs_ &
_non-conducteurs_.

Si quelque partie de matière électrique est appliquée à un morceau de
matière conductrice, elle le pénètre, coule au travers, ou se répand
également sur sa surface; si elle est appliquée à un morceau de matière
non conductrice, elle ne fera ni l'un ni l'autre. Il n'y a de
conducteurs parfaits de la matière électrique, que les métaux & l'eau;
les autres corps ne le sont qu'à proportion qu'il entre dans leur
composition du mêlange de ceux-ci; s'il n'y en a pas plus ou moins, ils
ne seront point du tout conducteurs.[10] Ceci, soit dit en passant,
montre entre les métaux & l'eau un nouveau rapport que l'on ignoroit
jusqu'à présent.

[Note 10: Cette proposition a été trouvée depuis trop générale: M.
Wilson ayant découvert que la cire fonduë & la résine sont aussi
conducteurs. On pourroit y ajoûter beaucoup d'autres exemples
semblables, comme celui de l'eau qui est un des plus excellens
conducteurs d'électricité tant qu'elle conserve sa fluidité, & qui cesse
de l'être, dès qu'elle la perd.]

Je vais tâcher d'éclaircir cela par une comparaison, qui cependant n'en
peut donner qu'une foible analogie. La matière électrique passe au
travers des conducteurs, comme l'eau passe au travers d'une pierre
poreuse, ou se répand sur leur surface, comme l'eau se répand sur une
pierre moüillée; mais quand cette matière est appliquée à des corps non
conducteurs, c'est comme l'eau qui dégoutte sur une pierre grasse; elle
ne la pénétre point, ne passe point à travers, ne s'étend point sur sa
surface; mais elle reste par gouttes sur les endroits où elle tombe.
Voyez à cet égard ma dernière piéce imprimée.

2e. _Question_. Quels sont les effets de l'air dans les expériences
électriques?

22. _Réponse_. Voici tous ceux que j'ai remarqués jusqu'à présent; l'air
humide reçoit & conduit la matière électrique à proportion de son
humidité; l'air parfaitement sec ne le fait point du tout; l'air doit
donc être mis dans la classe des non-conducteurs. L'air sec aide à fixer
l'atmosphère électrique autour du corps qu'elle environne, & en empêche
la dissipation; car dans le vuide elle se dissipe aisément, & les
pointes agissent plus fortement; c'est-à-dire, elles poussent ou
attirent la matière électrique plus librement & à de plus grandes
distances; en sorte que l'air survenant met quelque sorte d'obstacle à
ce qu'elle passe d'un corps à un autre. Une bouteille électrique bien
propre garnie de son fil-d'archal, remplie d'air au lieu d'eau, ne se
chargera, & ne donnera pas plus de choc que si elle étoit remplie de
verre pulvérisé; mais étant vuide d'air, elle produit autant d'effet que
si elle

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Text Comparison with Memoirs of Benjamin Franklin; Written by Himself. [Vol. 2 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

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And farther, _What maintains one vice would bring up two children_.
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at the mines of silver, to examine why they bring not in so much now as they did formerly.
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Remember that _time_ is money.
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Pamphilius was a Roman citizen, whose body upon his death was forbidden sepulture, his estate was confiscated, his house razed, and his wife and children banished the Roman territories, wholly for his having been a notorious and inveterate liar.
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And then, having yourselves thus lessened our encouragement for raising sheep, you curse us for the scarcity of mutton! I have heard my grandfather say, that the farmers submitted to the prohibition on the exportation of wool, being made to expect and believe that, when the manufacturer bought his wool cheaper, they should also have their cloth cheaper.
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However, since we could not be without a glass in the room, "My dear," saith she, "we may as well buy a large fashionable one, that Mr.
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At other times, when I came at the same hour, _she wondered I would stay so long, for dinner was ready about one, and had waited for me these two hours_.
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_Answer.
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She is of a most affectionate temper, and perfectly dutiful and obliging to her parents and to all.
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FRANKLIN.
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The time has been when the colonies might have been pleased with it, they are now _indifferent_ about it, and if it is much longer delayed, they too will _refuse_ it.
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Your writings, after all the abuse you and they have met with, begin to make serious impressions on those who at first rejected the counsels you gave; and they will acquire new weight every day, and be in high esteem when the cavils against them are dead and forgotten.
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With sincere and very great esteem, I am ever, my dear friend, yours most affectionately, "B.
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* * * * * CAUSES OF EARTHQUAKES.
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A fluid, moving from all points horizontally towards a centre, must, at that centre, either ascend or descend.
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part of a summer's day, or, it may be, for several days successively, till it is violently heated, together with the lower region of air in contact with it, so that the said lower air becomes specifically lighter than the superincumbent higher region of the atmosphere in which the clouds commonly float: let us suppose, also, that the air surrounding this tract has not been so much heated during those days, and, therefore, remains heavier.
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It has been proposed by philosophical writers, that to compute how much water any river discharges into the sea in a given time, we should measure its depth and swiftness at any part above the tide: as for the Thames, at Kingston or Windsor.
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Another.
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not pass so regularly and constantly backward and forward in the same track, I began to apprehend there might be something in it, and attempted to account for it from this consideration, that the boat, in proceeding along the canal, must in every boat's length of her course move out of her way a body of water equal in bulk to the room her bottom took up in the water; that the water so moved must pass on each side of her and under her bottom to get behind her; that if the passage under her bottom was straitened by the shallows, more of that water must pass by her sides, and with a swifter motion, which would retard her, as moving the contrary way; or, that the water becoming lower behind the boat than before, she was pressed back by the weight of its difference in height, and her motion retarded by having that weight constantly to overcome.
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_ METHOD OF CONTRACTING CHIMNEYS.