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

By Benjamin Franklin

Page 181


May not all the phenomena of light be more conveniently solved, by
supposing universal space filled with a subtle elastic fluid, which,
when at rest, is not visible, but whose vibrations affect that fine
sense in the eye, as those of air do the grosser organs of the ear?
We do not, in the case of sound, imagine that any sonorous particles
are thrown off from a bell, for instance, and fly in strait lines to
the ear; why must we believe that luminous particles leave the sun
and proceed to the eye? Some diamonds, if rubbed, shine in the dark,
without losing any part of their matter. I can make an electrical
spark as big as the flame of a candle, much brighter, and, therefore,
visible further; yet this is without fuel; and, I am persuaded,
no part of the electric fluid flies off in such case to distant
places, but all goes directly, and is to be found in the place to
which I destine it. May not different degrees of the vibration of
the above-mentioned universal medium, occasion the appearances of
different colours? I think the electric fluid is always the same; yet
I find that weaker and stronger sparks differ in apparent colour,
some white, blue, purple, red; the strongest, white; weak ones red.
Thus different degrees of vibration given to the air produce the
seven, different sounds in music, analagous to the seven colours, yet
the medium, air, is the same.

If the Sun is not wasted by expence of light, I can easily conceive
that he shall otherwise always retain the same quantity of matter;
though we should suppose him made of sulphur constantly flaming. The
action of fire only _separates_ the particles of matter, it does not
_annihilate_ them. Water, by heat raised in vapour, returns to the
earth in rain; and if we could collect all the particles of burning
matter that go off in smoak, perhaps they might, with the ashes,
weigh as much as the body before it was fired: and if we could put
them into the same position with regard to each other, the mass would
be the same as before, and might be burnt over again. The chymists
have analysed sulphur, and find it composed, in certain proportions,
of oil, salt, and earth; and having, by the analysis, discovered
those proportions, they can, of those ingredients, make sulphur.
So we have only to suppose, that the parts of the Sun's sulphur,
separated by fire, rise into his atmosphere, and there being freed
from the immediate action of the fire, they collect into cloudy

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Text Comparison with Experiments and Observations on Electricity Made at Philadelphia in America

Page 3
Place an electrised phial on wax; a small cork-ball suspended by a dry silk-thread held in your hand, and brought near to the wire, will first be attracted, and then repelled: when in this state of repellency, sink your hand, that the ball may be brought towards the bottom of the bottle; it will there be instantly and strongly attracted, 'till it has parted with its fire.
Page 5
Take off the bottle, and holding it in your hand, touch the other with the wire; that book will be electrised _plus_; the fire passing into it from the wire, and the bottle at the same time supply'd from your hand.
Page 6
If you would have the whole filletting round the cover appear in fire at once, let the bottle and wire touch the gold in the diagonally opposite corners.
Page 9
Thus you may circulate it, as Mr _Watson_ has shewn; you may also accumulate or substract it upon or from any body, as you connect that body with the rubber or with the receiver, the communication with the common stock being cut off.
Page 10
--We fire spirits with the wire of the phial.
Page 12
If the phials were both charged through their hooks, the cork, when it has been attracted and repell'd by the one, will not be attracted, but equally repelled by the other.
Page 15
remain in the first bottle.
Page 20
--Even a thoroughly wet pack-thread sometimes fails of conducting a shock, tho' it otherwise conducts electricity very well.
Page 21
_ [Illustration] LETTER IV.
Page 23
If the particles of water bring electrical fire when they attach themselves to air, the repulsion between the particles of water electrified, joins with the natural repulsion of the air, to force its particles to a greater distance, whereby the triangles are dilated, and the air rises, carrying up with it the water.
Page 26
Two gun-barrels united, and as highly electrified, will give a spark at a still greater distance.
Page 29
And accordingly some old sea-captains, of whom enquiry has been made, do affirm, that the fact agrees perfectly with the hypothesis; for that, in crossing the great ocean, they seldom meet with thunder till they come into soundings; and that the islands far from the continent have very little of it.
Page 33
--Those points will also discharge into the air, when the body has too great an electrical atmosphere, without bringing any non-electric near, to receive what is thrown off: For the air, though an electric _per se_, yet has always more or less water and other non-electric matters mixed with it; and these attract.
Page 34
These explanations of the power and operation of points, when they first occurr'd to me, and while they first floated in my mind, appeared perfectly satisfactory; but now I have wrote them, and consider'd them more closely in black and white, I must own I have some doubts about them: yet as I have at present nothing better to offer in their stead, I do not cross them out: for even a bad solution read, and its faults discover'd, has often given rise to a good one in the mind of an ingenious reader.
Page 35
I have a large prime conductor made of several thin sheets of Fuller's pasteboard form'd into a tube, near 10 feet long and a foot diameter.
Page 38
Lightning melts metals, and I hinted in my paper on that subject, that I suspected it to be a cold fusion; I do not mean a fusion by force of cold, but a fusion without heat.
Page 40
10 the upper corner.
Page 42
Now let the globe be turned, and you see a spark strike from the bullet to the wire of the bottle, and the same instant you see and feel an exactly equal spark striking from the coating on your knuckle, and so on spark for spark.
Page 47
----And every other appearance I have yet seen, in which glass and electricity are concern'd, are, I think, explain'd with equal ease by the same hypothesis.
Page 50
electrical fire from the floor to the cushion; then, if there be no fine points or hairy threads sticking out from the cushion, or from the parts of the machine opposite to the cushion, (of which you must be careful) you can get but a few sparks from the prime conductor, which are all the cushion will part with.