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had beaten Braddock did not at most exceed four hundred Indians and French together, instead of proceeding, and endeavoring to recover some of the lost honor, he ordered all the stores, ammunition, etc., to be destroyed, that he might have more horses to assist his flight toward the settlements, and less lumber to remove. He was there met with requests from the governors of Virginia, Maryland and Pennsylvania that he would post his troops on the frontiers, so as to afford some protection to the inhabitants ; but be continued his hasty march through all the country, not thinking himself safe till he arrived at Philadelphia, where the inhabitants could protect him. This whole transaction gave us Americans the first suspicion that our exalted ideas of the prowess of British regulars bad not been well founded.

FRANKLIN'S DISCOVERY OF THE POSITIVE AND NEGATIVE STATES OF

ELECTRICITY.

(From the Letter to Peter Collinson, July 11, 1747.]

We suppose, as aforesaid, that electrical fire is a common element, of equal share before any operation is begun with the tube. A, who stands on wax and rubs the tube, collects the electrical fire from himself into the glass; and, his communication with the common stock being cut off by the wax, his body is not again immediately supplied. B, (who stands on wax likewise) passing his knuckle along near the tube, receives the fire which was collected by the glass from A; and his communication with the common stock being likewise cut off, he retains the additional quantity received. To C, standing on the floor, both appear to be electrized; for he, having only the middle quantity of electrical fire, receives a spark upon approaching B, who has an over quantity; but gives one to A, who has an under quantity. If A and B approach to touch each other, the spark is stronger, because the difference between them is greater. After such touch there is no spark between either of them and C, because the electrical fire in all is reduced to the original equality. If they touch while electrizing, the equality is never de. stroyed, the fire only circulating. Hence have arisen some new terms among us; we say B (and bodies like circumstanced) is electrized positively; A, negatively. Or rather, B is electrized plus; A, minus. And we daily in our experiments electrize bodies plus or minus, as we think proper. To electrize plus or minus, no more needs to be known than this, that the parts of the tube or sphere that are rubbed, do, in the in.

stant of the friction, attract the electrical fire, and therefore take it from the thing rubbing; the same parts immediately, as the friction upon them ceases, are disposed to give the fire they have received to any body that has less.

HIS INVENTION OF THE LIGHTNING ROD.

[Opinions

arising from Experiments and Observations made at Phila

delphia, 1749.]

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OW if the fire of electricity and that of lightning be the same, as I

have endeavored to show at large in a former paper, this pasteboard tube and these scales may represent electrified clouds.

trified clouds. If a tube of only ten feet long will strike and discharge its fire on the punch at two or three inches distance, an electrified cloud of perhaps ten thousand acres may strike and discharge on the earth at a proportionately greater distance, The horizontal motion of the scales over the floor may represent the motion of the clouds over the earth; and the erect iron punch, a hill or high building; and then we see how electrified clouds passing over hills or high buildings at too great a height to strike, may be attracted lower till within their striking distance. And, lastly, if a needle fixed on the punch with its point upright, or even on the floor below the punch, will draw the fire from the scale silently at a much greater than the striking distance, and so prevent its descending toward the punch ; or if in its course it would have come nigh enough to strike, yet being first deprived of its fire it cannot, and the punch is thereby secured from the stroke; I say, if these things are so, may not the knowledge of this power of points be of use to mankind, in preserving houses, churches, ships, etc., from the stroke of lightning, by directing us to fix, on the highest parts of those edifices, upright rods of iron made sharp as a needle, and gilt to prevent rusting, and from the foot of those rods a wire down the outside of the building into the ground, or down round one of the shrouds of a ship, and down her side till it reaches the water? Would not these pointed rods probably draw the electrical fire silently out of a cloud before it came nigh enough to strike, and thereby secure us from that most sudden and terrible mischief?

THE ELECTRICAL KITE.

(Letter to Collinson, October 19, 1752.]

AS in

success of the Philadelphia experiment for drawing the electric fire from clouds by means of pointed rods of iron erected on high buildings, etc., it may be agreeable to the curious to be informed that the same experiment has succeeded in Philadelphia, though made in a different and more easy manner, which is as follows.

Make a small cross of two light strips of cedar, the arms so long as to reach to the four corners of a large thin silk handkerchief when extended ; tie the corners of the handkerchief to the extremities of the cross, so you have the body of a kite; which, being properly accommodated with a tail, loop, and string, will rise in the air, like those made of paper; but this being of silk is fitter to bear the wet and wind of a thunder-gust without tearing. To the top of the upright stick of the cross is to be fixed a very sharp-pointed wire, rising a foot or more above the wood. To the end of the twine, next the hand, is to be tied a silk ribbon, and where the silk and twine join, a key may be fastened.

This kite is to be raised when a thunder-gust appears to be coming on, and the person who holds the string must stand within a door or window, or under some cover, so that the silk ribbon may not be wet; and care must be taken that the twine does not touch the frame of the door or window. As soon as any of the thunder-clouds come over the kite, the pointed wire will draw the electric fire from them, and the kite, with all the twine, will be electrified, and the loose filaments of the twine will stand out every way, and be attracted by an approaching finger. And when the rain has wetted the kite and twine, so that it can conduct the electric fire freely, you will find it stream out plentifully from the key on the approach of your knuckle. At this key the pbial may be charged; and from electric fire thus obtained, spirits may be kindled, and all the other electric experiments be performed, which are usually done by the help of a rubbed glass globe or tube, and thereby the sameness of the electric matter with that of lightning completely demonstrated.

THAT LIGHTNING USUALLY PASSES FROM EARTH TO THE CLOUDS.

(Letter to Collinson, September, 1753.]

AT last, on the 12th of April, 1763, there being a smart gust of some

continuance, I charged one phial pretty well with lightning, and

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the other equally, as near as I could judge, with electricity from my glass globe; and, having placed them properly, I beheld, with great surprise and pleasure, the cork ball play briskly between them, and was convinced that one bottle was electrized negatively.

I repeated this experiment several times during the gust, and in eight succeeding gusts, always with the same success; and being of opinion (for reasons I formerly gave in my letter to Mr. Kinnersley, since printed in London), that the glass globe electrizes positively, I concluded that the clouds are always electrized negatively, or have always in them less than their natural quantity of the electric fluid.

Yet, notwithstanding so many experiments, it seems I concluded too soon; for at last, June the 6th, in a gust which continued from five o'clock, P.M., to seven, I met with one cloud that was electrized positively, though several that passed over my rod before, during the same gust, were in the negative state. This was thus discovered.

But this was a single experiment, which, however, destroys my first too general conclusion, and reduces me to this: That the clouds of a thun. der-gust are most commonly in a negative state of electricity, but sometimes in a positive state.

The latter I believe is rare; for, though I, soon after the last experiment, set out on a journey to Boston, and was from home most part of the summer, which prevented my making farther trials and observations; yet Mr. Kinnersley, returning from the Islands just as I left home, pursued the experiments during my absence, and informs me that he always found the clouds in the negative state.

So that, for the most part, in thunder-strokes, it is the earth that strikes into the clouds, and not the clouds that strike into the earth.

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A THEORY OF LIGHT AND HEAT.

UNIVERS

(Loose Thoughts on a Universal Fluid. 1784.]
IVERSAL space, as far as we know of it, seems to be filled with

a subtile fluid, whose motion, or vibration, is called light.
In such case, as there may be a continuity or communication of this
fluid through the air quite down to the earth, is it not by the vibrations
given to it by the sun that light appears to us; and may it not be that
every one of the infinitely small vibrations, striking common matter with
a certain force, enters its substance, is held there by attraction, and aug.
mented by succeeding vibrations, till the matter has received as much
as their force can drive into it?

Is it not thus that the surface of this globe is continually heated by such repeated vibrations in the day, and cooled by the escape of the heat, when those vibrations are discontinued in the night, or intercepted and reflected by clouds ?

THE WAY TO WEALTH.

[From a Discourse prefixed to Poor Richard's Almanacfor 1757.) TOURTEOUS Reader, COURT

I have heard that nothing gives an author so great pleasure as to find his works respectfully quoted by others. Judge, then, how much I must have been gratified by an incident I am going to relate to you. I stopped my horse lately, where a great number of people were collected at an auction of merchants' goods. The hour of the sale not being come, they were conversing on the badness of the times; and one of the company called to a plain, clean old m.n, with white locks, "Pray, Father Abraham, what think you of the times? Will not these heavy taxes quite ruin the country? How shall we ever be able to pay them? What would

you advise us to do?” Father Abraham stood up and replied, "If you would have my advice, I will give it you in short; for A word to the wise is enough, as Poor Richard says." They joined in desiring him to speak his mind, and gathering round him he proceeded as follows.

" Friends," said he, “the taxes are indeed very heavy, and, if those laid on by the government were the only ones we had to pay, we might more easily discharge them; but we have many others, and much more grievous to some of us. We are taxed twice as much by our idleness, three times as much by our pride, and four times as much by our folly; and from these taxes the commissioners cannot ease or deliver us by allowing an abatement. However, let us hearken to good advice, and something may be done for us; God helps them that help themselves, as Poor Richard says.

“I. It would be thought a hard government that should tax its people one-tenth part of their time, to be employed in its service; but idleness taxes many of us much more; sloth, by bringing on diseases, absolutely shortens life. Sloth, like rust, consumes faster than labor wears ; while the used key is always bright, as Poor Richard says. But dost thou love life, then do not squander time, for that is the stuff life is made of, as Poor Richard. says. How much more than is necessary do we spend in sleep, forgetting, that The sleeping fox catches no poultry, and that, There will be sleeping enough in the grave, as Poor Richard says.

"If time be of all things the most precious, wasting time must be,, as Poor

TOL. III.--2

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