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employed in such observations on your side the water, it is probable some one or other has hit on them before." From the beginning to the end of his life, he observed the same modest and cautious method of communication. The first philosophical paper inserted in his collection, in 1756, is entitled " Physical and Meteorological Observations, Conjectures and Suppositions;" and his last at Passy, in 1784, are of a similar title, viz. “Meteorological Imaginations and Conjectures. Loose Thoughts on an Universal Fluid," and the like.

But I return to the account of his eletrical labours, and the materials on which they were grounded. Von Kliest, about the latter end of the year 1745, had accidentally discovered some of the powers and properties of what is called the Leyden-phial, and sent an account of the same to Lieberkhun at Berlin, which soon made this branch of science more interesting. As soon as the account of this discovery reached America, (together with Mr. Collinson's tube) it excited no less curiosity here, than it had done in Europe; and Dr. Franklin writes to his friend Collinson in September, 1747, " that no less than one hundred large glass tubes had been sold in Philadelphia, in,the space of four months preceding." But although Von Kliest had discovered some properties of this phial, and Muschenbroek, to his cost, had experienced others (by which the phial, or bottle received his name) it remained for Dr. Franklin to discover its true principles, and how, by means of it, to accumulate, retain, and discharge any quantity of the electric fluid, with safety. The account of this dis, covery and of the experiments on which it was

founded, he communicated to Mr. Collinson, in his letter of September 1, 1747, with his usual caution and modesty, in the following terms.

"The necessary trouble of copying long letters, which, perhaps, when they come to your hands may contain nothing new, or worth your reading (so quick is the progress made with you in electricity) half discourages me from writing more on that subject. Yet I cannot forbear adding a few observations on M. Muschenbroek's wonderful bottle." In this letter, he discloses the whole magical powers of this bottle; by proving that it would receive an accumulation of the electric fluid on the inside, only as it discharged an equal quantity from the outside. This discovery gave him the greatest advantages over all the electricians of Europe. It put into his hands (as it were) the key which opened into all the secrets of electricity, and enabled him to make his succeeding experiments, with a sure aim, while his brethren in Europe were groping in the dark, and some of them falling martyrs to their experiments.

He was the first who fired gun-powder, gave magnetism to needles of steel, melted metals, and killed animals of considerable size, by means of electricity. He was the first who informed electricians, and the world in general, of the power of matalline-points, in conducting the electric fluid; acknowledging at the same time, with a candour worthy of true philosophy, that he received the first information of this power from Mr. Thomas Hopkinson*, who had used such

"This power of points, to throw off the electrical fire, was first commu nicated to me by my ingenious friend, Mr. Thomas Hopkinson, since

points, expecting by their means to precure a more powerful and concentrated discharge of the Leydenphial; but found the effect to be directly contrary. It was, undoubtedly, the discovery of this wonderful power of metalline-points, in carrying off and silently dispersing the electric-fluid when accumulated, and the similarity and resemblance which he observed between the effects of lightning and electricity, which first suggested to him the sublime and astonishing idea of draining the clouds of their fire, and disarming the thunder of its terrors; flattering himself at the same time with the pleasing hopes of gratifying a desire, long before become habitual to him, of rendering this discovery in some manner useful and beneficial to his fellow-creatures. This appears by his notes of November 7, 1749, when enumerating all the known particulars of resemblance between lightning and electricity, he concludes with saying-" The electric fluid is attracted by points. We do not know whether this property be in lightning; but since they agree in all the particulars in which we can already compare them, it is possible that they agree likewise in this: Let the experiment be made." Difficulties, without doubt, occurred in making this experiment, both as to the manner and least expensive way of reaching the clouds with his points; for we do not find that he accomplished his grand experiment, till in June 1752. In a letter to his friend Collinson, not dated, but probably written in 1749, he commu

deceased; whose virtue and integrity, in every station of life, public and. private, will ever make his memory dear to those who knew him, and knew how to value him."

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nicates his "Observations and suppositions towards forming a new hypothesis, for explaining the several phænomena of thunder-gusts;" which was followed in July, 1750, by another letter to the same, containing opinions and conjectures concerning the properties and effects of the electric matter," and giving particular directions for determining whether clouds containing lightning are electrified or not; for ascertaining of which, his idea at this time was, "the placing a pointed iron-rod on some high tower or steeple, and attempting to draw sparks from it," there being at that time no lofty spires in Philadelphia. But his ever-inventive genius, which could derive lessons of philosophy even from the play of children, soon furnished him with a more simple and less expensive method: For in June 1752, he took the opportunity of an approaching thunder-storm, to walk into a field, where there was a shed convenient for his purpose. Dreading the ridicule which too commonly attends unsuccessful attempts in science, he communicated his intended experiment to no person but his son, who assisted him in raising a kite, which he had prepared of a large silk handkerchief, extended by two cross-sticks. After waiting for some time, and almost beginning to despair of success, he drew the first spark with his knuckle from a key suspended to the string of the kite. Another and another succeeded; and as the string became wet, he collected fire copiously. What must have been his raptures on the success of this grand experiment; leading him to anticipate that happy and beneficent application of the principles of electricity, to the sav

ing of life and property, which alone would have recorded his name among the benefactors of mankind; even if his discoveries of those principles could never have been extended or applied to any other useful purpose in the world. Similar must his raptures have been to those of a Newton, when by applying the laws of gravitation and projection first to the moon, he was enabled to extend them to the whole Solar-system, as is beautifully described by the poet

What were his raptures then! how pure! how strong!
And what the triumphs of old Greece and Rome
With his compar'd-When Nature and her laws
Stood all subdued by Him, and open laid
Their every latent Glory to his view.

All intellectual Eye; our Solar round
First gazing thro', he by the blended Power
Of Gravitation and Projection saw

The whole in silent Harmony revolve.

First to the neighb'ring Moon this mighty Key
Of Nature he applied-Behold! it turn'd

The secret wards; it open'd wide the course
And various aspects of the Queen of Night;
Whether she wanes into a scanty Orb

Or, waxing broad, with her pale shadowy Light,
In a soft Deluge overflows the Sky*.

Dr. Franklin's Letters, giving an account of his electrical experiments and discoveries, and, among the rest, of this grand experiment of drawing electricity from the clouds, were soon published in Europe, and translated into different languages. "Nothing "was ever written on the subject of electricity,"

• Thomson's poem to the memory of Sir Isaac Newton.

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