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

By Benjamin Franklin

Page 169

wire, is not necessary; for _in vacuo_ the electrical fire will fly
freely from the inner surface, without a non-electric conductor: but
air resists in motion; for being itself an electric _per se_, it
does not attract it, having already its quantity. So the air never
draws off an electric atmosphere from any body, but in proportion to
the non-electrics mixed with it: it rather keeps such an atmosphere
confined, which, from the mutual repulsion of its particles, tends to
dissipation, and would immediately dissipate _in vacuo_.--And thus
the experiment of the feather inclosed in a glass vessel hermetically
sealed, but moving on the approach of the rubbed tube, is explained.
When an additional quantity of the electrical fluid is applied to
the side of the vessel by the atmosphere of the tube, a quantity
is repelled and driven out of the inner surface of that side into
the vessel, and there affects the feather, returning again into its
pores, when the tube with its atmosphere is withdrawn; not that the
particles of that atmosphere did themselves pass through the glass to
the feather. And every other appearance I have yet seen, in which
glass and electricity are concerned, are, I think, explained with
equal ease by the same hypothesis. Yet, perhaps, it may not be a true
one, and I shall be obliged to him that affords me a better.

35. Thus I take the difference between non-electrics, and glass, an
electric _per se_, to consist in these two particulars. 1st, That a
non-electric easily suffers a change in the quantity of the electric
fluid it contains. You may lessen its whole quantity, by drawing
out a part, which the whole body will again resume; but of glass
you can only lessen the quantity contained in one of its surfaces;
and not that, but by supplying an equal quantity at the same time
to the other surface: so that the whole glass may always have the
same quantity in the two surfaces, their two different quantities
being added together. And this can only be done in glass that is
thin; beyond a certain thickness we have yet no power that can make
this change. And, 2dly, that the electric fire freely removes from
place to place, in and through the substance of a non-electric, but
not so through the substance of glass. If you offer a quantity to
one end of a long rod of metal, it receives it, and when it enters,
every particle that was before in the rod pushes its neighbour quite
to the farther end, where the overplus is discharged; and

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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]

Page 11
318 9: for descent, read decent.
Page 51
Page 80
Page 131
to keep a _look-out before_ in the channel, but at sea it has been neglected.
Page 141
A man who can swim, may be aided in a long traverse by his handkerchief formed into a kite, by two cross sticks extending to the four corners; which, being raised in the air when the wind is fair and fresh,.
Page 147
Page 156
| | --| 12 | | | 77 | | | 175 |38 2|50 1| | | --| | 4 | | 77 | | | | | | | | 9| 9 | | 75 | 77 | | | | | | | | --| 12 | | 75 | 70 | SW | N33E | 175 |39 39|46 55| | ------------------------------------------------------------------------ OBSERVATIONS MADE ON BOARD THE REPRISAL, CONTINUED.
Page 160
|Air|Water|Air|Water|Winds|Course|tance |of the| | | | N.
Page 205
Warm the tube, and you will find, as long as it continues warm, a constant current of air entering below and passing up through it, till discharged at the top; because the warmth of the tube being communicated to the air it contains rarefies that air and makes it lighter than the air without, which therefore presses in below, forces it upwards, and follows and takes its place, and is rarefied in its turn.
Page 208
This however has its limits; for experience shows, that no increased velocity, so occasioned, has made the admission of air through the key-hole equal in quantity to that through an open door; though through the door the current moves slowly, and through the key-hole with great rapidity.
Page 236
_ _In.
Page 252
Two other sheets are then fixed together, according to the first and second operations above, and their seam, with the reeve, introduced under the upper ends of the seam of the former, so as to cover down about two inches upon the upper ends of the former sheets: and so far the cartridge paper is allowed to cover the two first sheets.
Page 282
Page 322
I think the cap was nevertheless an advantage to us, for it was the first thing that put our girls upon knitting worsted mittens for sale at Philadelphia, that they might have wherewithal to buy caps and ribbons there, and you know that that industry has continued, and is likely to continue and increase to a much greater value, and answer better purposes.
Page 338
With unchangeable esteem and affection, I am, my dear friend, Ever yours.
Page 362
how occasioned, 120, 128.
Page 365
Page 372
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Page 393
'decending' replaced by 'descending'.