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

By Benjamin Franklin

Page 208

down Lightning.--No
satisfactory Hypothesis respecting the Manner in which Clouds
become electrified.--Six Men knocked down at once by an electrical
Shock.--Reflections on the Spirit of Invention._


_Philadelphia, March 18, 1755._

SIR,

I send you enclosed a paper containing some new experiments I have
made, in pursuance of those by Mr. Canton that are printed with my
last letters. I hope these, with my explanation of them, will afford
you some entertainment[66].

In answer to your several enquiries. The tubes and globes we use
here, are chiefly made here. The glass has a greenish cast, but is
clear and hard, and, I think, better for electrical experiments than
the white glass of London, which is not so hard. There are certainly
great differences in glass. A white globe I had made here some years
since, would never, by any means, be excited. Two of my friends tried
it, as well as myself, without success. At length, putting it on an
electric stand, a chain from the prime conductor being in contact
with it, I found it had the properties of a non-electric; for I could
draw sparks from any part of it, though it was very clean and dry.

All I know of Domien, is, that by his own account he was a native of
Transylvania, of Tartar descent, but a priest of the Greek church:
he spoke and wrote Latin very readily and correctly. He set out
from his own country with an intention of going round the world, as
much as possible by land. He travelled through Germany, France, and
Holland, to England. Resided some time at Oxford. From England he
came to Maryland; thence went to New England; returned by land to
Philadelphia; and from hence travelled through Maryland, Virginia,
and North Carolina to you. He thought it might be of service to him
in his travels to know something of electricity. I taught him the
use of the tube; how to charge the Leyden phial, and some other
experiments. He wrote to me from Charles-Town, that he had lived
eight hundred miles upon electricity, it had been meat, drink, and
cloathing to him. His last letter to me was, I think, from Jamaica,
desiring me to send the tubes you mention, to meet him at the
Havannah, from whence he expected to get a passage to La Vera Cruz;
designed travelling over land through Mexico to Acapulco; thence to
get a passage to Manilla, and so through China, India, Persia, and
Turkey, home to his own country; proposing to support himself chiefly
by electricity. A strange

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

Page 1
_ _It has, indeed, been of late the fashion to ascribe every grand or unusual operation of nature, such as lightening and earthquakes, to electricity; not, as one would imagine, from the manner of reasoning on these occasions, that the authors of these schemes have, discovered any connection betwixt the cause and effect, or saw in what manner they were related; but, as it would seem, merely because they were unacquainted with any other agent, of which it could not positively be said the connection was impossible.
Page 2
_ whatever quantity of electrical fire is thrown in at top, an equal quantity goes out of the bottom.
Page 6
Lay the book on a glass or wax; and on the other end of the gold lines, set the bottle electrised: then bend the springing wire, by pressing it with a stick of wax till its ring approaches the ring of the bottle wire; instantly there is a strong spark and stroke, and the whole line of gold, which completes the communication between the top and bottom of the bottle, will appear a vivid flame, like the sharpest lightning.
Page 9
Hence have arisen some new terms among us: we say, _B_, (and bodies like circumstanced) is electrised _positively_; _A_, _negatively_.
Page 11
_London_.
Page 22
14.
Page 26
37.
Page 27
Hence thunder-gusts after heats, and cool air after gusts; the water and the clouds that bring it, coming from a higher and therefore a cooler region.
Page 28
When electrical fire strikes thro' a body, it acts upon the common fire contained in it, and puts that fire in motion; and if there be a sufficient quantity of each kind of fire, the body will be inflamed.
Page 30
From these three things, the extreme subtilty of the electrical matter, the mutual repulsion of its parts, and the strong attraction between them and other matter, arise this effect, that when a quantity of electrical matter, is applied to a mass of common matter, of any bigness or length within our observation (which has not already got its quantity) it is immediately and equally diffused through the whole.
Page 31
14.
Page 32
The atmosphere of electrical particles surrounding an electrified sphere, is not more disposed to leave it or more easily drawn off from any one part of the sphere than from another, because it is equally attracted by every part.
Page 33
But there is a small portion between I, B, K, that has less of the surface to rest on, and to be attracted by, than the neighbouring portions, while at the same time there is a mutual repulsion between its particles and the particles of those portions, therefore here you can get it with more ease or at a greater distance.
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 36
But if a needle be stuck on the end of the punch, its point upwards, the scale, instead of drawing nigh to the punch and snapping, discharges its fire silently through the point, and rises higher from the punch.
Page 38
Hence we concluded that the pigeon also had been absolutely blinded by the shock.
Page 41
You may make this figure so acute below and blunt above, as to need no under plate, it discharging fast enough into the air.
Page 44
more of this electrical fluid than other common matter: That when it is blown, as it cools, and the particles of common fire leave it, its pores become a vacuum: That the component parts of glass are extremely small and fine, I guess from its never showing a rough face when it breaks, but always a polish; and from the smallness of its particles I suppose the pores between them must be exceeding small, which is the reason that Aqua-fortis, nor any other menstruum we have, can enter to separate them and dissolve the substance; nor is any fluid we know of, fine enough to enter, except common fire, and the electrical fluid.
Page 46
[12] If the tube be exhausted of air, a non electric lining in contact with the 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 its motion; for being itself an electric _per se_, it does not attract it, having already its quantity.
Page 54
[7] See the ingenious essays on electricity in the Transactions, by Mr Ellicot.