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ber of experiments, but added little of importance. He first used the terms conductors and electrics, per se. 1742, several ingenious Germans engaged in this subject. Of these the principle were, professor Boze of Whittemberg, professor Winkler of Leipsic, Gordon, a Scotch Benedictine monk, professor of philosophy at Erfurt, and Dr. Ludolf of Berlin. The result of their researches astonished the philosophers of Europe. Their apparatus was large, and by means of it they were enabled to collect large quantities of electricity, and thus to produce phenomena which had been hitherto unobserved. They killed small birds, and set spirits on fire. Their experiments excited the curiosity of other philosophers. Collinson about the year 1745, sent to the library company of Philadelphia an account of these experiments, together with a tube, and directions how to use it. Franklin, with some of his friends, immediately engaged in a course of experiments; the result of which is well known. He was enabled to make a number of important discoveries, and to propose theories to account for various phenomena ; which have been universally adopted, and which bid fair to endure for ages. His observations he communicated, in a series of letters, to his friend Collinson ; the first of which is dated March 28th, 1747. In these he makes known the power of points in drawing and throwing off the electrical matter, which had hitherto escaped the notice of electricians. He also made the grand discovery of a plus and minus, or of a positive and negative state of electricity. We give him the honour of this, without hesitation; although the English have claimed it for their countryman Dr. Watson.
Watson's paper is dated January 21, 1748; Franklin's July 11, 1747; several months prior. Shortly after, Franklin, from his principles of plus and minus state, explained, in a satisfactory manner, the phenomena of the Leyden phial, first observed by Mr. Cuneus, or by professor Muschenbroeck of Leyden, which had much perplexed philosophers. He showed clearly that the bottle, when charged, contained no more electricity than before, but
that as much was taken from the one side as was thrown on the other; and that, to discharge it nothing was necessary but to make a communication between the two sides, by which the equilibrium might be restored, and that then no signs of electricity would remain.
He afterwards demonstrated, by experiments, that the electricity did not reside in the coating, as had been supposed, but in the pores of the glass itself. After a phial was charged, he removed the coating, and found that upon applying a new coating the shock might still be received. In the year 1749, he first suggested his idea of explaining the phenomena of thundergusts, and of the aurora borealis, upon electrical principles. He points out many particulars in which lightning and electricity agrec; and he adduces many facts, and reasoning frons facts, in support of his positions. In the same year he conceived the astonishingly bold and grand idea of ascertaining the truth of his doctrine, by actually drawing down the forked lightning, by means of sharppointed iron rods raised into the region of the clouds. Even in this uncertain state, his passion to be useful to mankind displays itself in a powerful manner. Admitting the identity of electricity and lightning, and knowing the power of points in repelling bodies charged with electricity, and in conducting their fire silently and imperceptibly, he suggests the idea of securing houses, ships, &c. from being damaged by lightning, by crecting pointed iron rods, which should rise some feet above the most elevated part, and descend some feet into the ground or the water. The effect of these, he concluded, would be either to prevent a stroke by repelling the cloud beyond the striking distance, or by drawing off the electrical fire which it contained ; or, if they could not effect this, they would at least conduct the stroke to the earth, without any injury to the building.
It was not until the summer of 1752, that he was enabled to complete his grand and unparalleled discovery by experiment. The plan which he had original
ly proposed, was to erect on some high tower, or other elevated place, a centry-box, from which should rise a pointed iron rod, insulated by being fixed in a cake of resin. Electrified clouds passing over this, would he conceived, impart to it a portion of their electricity, which would be rendered evidert to the senses by sparks being emitted, when a key, a knuckle, or other conductor, was presented 10 it Philadelphia at this time afforded no opportunity of trying an experiment of this kind.
Whilst Franklin was waiting for the erection of a spire, it occurred to him, that he might have more reaely access to the region of clouds by means of a common kite. He prepared one by attaching two cross sticks to a silk handkerchief, which would not suffer so much from the rain as paper. To his upright stick was fixed an iron point. The string was, as usual, of hemp, except the lower end, which was silk. Where the hempen string terminated, a key was fastened. With this apparatus, on the appearance of a thunder gust approaching, he went into the commons, accompanied by his son, to whom alone he communicated his intentions, well knowing the ridicule which too generally for the interest of science, awaits unsuccessful experiments in philosophy
He placed himself under a shed to avoid the rain. His kite was raised. A thunder cloud passed over it. No signs of electricity appeared. He almost despaired of success; when suddenly he observed the loose fibres of his string move towards an erect position. He now presented his knuckle to the key, and received a strong spark How exquisite must his sensations have been at this moment ! 'On this experiment depended the fate of his theory. If he succeeded, his name would rank high amongst those who have improved science ; if he failed, he must inevitably be subjected to the derision of mankind, or, what is worse, their pity, as a well-meaning man, but a weak, silly projector. Thé anxiety with which he looked for the result of his experiment, may 'easily be conceived. Doubts and despair had begun to prevail, when the fact was ascertained in so clear a manner, that even the most incredulous could no longer withhold their assent. Repeated sparks were drawn from the key, a phial was charged, a shock given, and all the expe riments made, which are usually performed with electricity.
About a month before this period some ingenious Frenchman had completed the discovery, in the manner originally proposed by Dr. Franklin. The letters which he sent to Mr. Collinson, it is said, were refused a place amongst the papers of the Royal Society of London. However, this may be, Collinson published them in a separate volume, under the title of New Experim nts and Observations on Electricity, made at Philadelphia in America. They were read with avi. dity, and soon translated into different languages. A very incorrect French translation fell into the liands of the celebrated Buffon, who notwithstanding the disadvantages under which the work laboured, was much pleased with it, and repeated the experiments with suc
He prevailed upon his friend, M. D'Alibard, to give his countrymen a more correct translation of the work of the American electrician. This contributed much towards spreading a knowledge of Franklin's principles in France. The king, Louis XV, hearing of these experiments expressed a wish to be a spectator of them. A course of experiments was given at the seat of the Duc D’Ayen, at St. Germaine, by M. de Lor. The applauses which the king bestowed upon Franklin, excited in Buffon, D’Alibard, and De Lor, an earnest desire of ascertaining the truth of his theory of thunder-gusts. Buffon erected his apparatus on the tower of Montbar. M. D'Alibard at Mary-la-ville, and De Lor at his house in the Estrapade at Paris, some of the highest ground in that capital D'Alibard's machine first showed signs of electricity. On the tenth of May, 1752, a thunder cloud passed over it, in the absence of M. D'Alibard; and a number of sparks were drawn from it by Coiffier, a joiner, with whom D’Alibard had left directions how
to proceed, and by M. Raulet, the prior of Mary-laville. An account of this experiment was given to the Royal Academy of Sciences, in a memoir by M. D’Alibard, dated May 13th, 1752. On the 18th of May, M. De Lor proved equally successful with the apparatus erected at his own house. These discoveries soon excited the philosophers of other parts of Europe to repeat the experiment. Amongst these, none signalized themselves more than father Beccaria of Turin, to whose observations science is much indebted. Even the cold regions of Russia were penetrated by the ardor for discovery. Professor Richman bade fair to add much to the stock of knowledge on this subject, when an unfortunate flash from his rod put a period to his existence. The friends of science will long remember with regret the admirable martyr to electricity.
By these experiments Franklin's theory was established in the most firm manner. When the truth of it could no longer be doubted, the vanity of men endeavoured to detract from its merit. That an American, an inhabitant of the obscure city of Philadelphia, the name of which was hardly known, should be able to make discoveries, and to frame theories, which had escaped the notice of the enlightened philosophers of Europe, was too mortifying to be admitted. He must certainly have taken the idea from somebody else. An American, a being of an inferior order, make discoveries! Impossible. It was said, that the Abbe Nollet, in 1748, had suggested the idea of the similarity of lightning and electricity, in his Lecors de Physique. It is true, that the Abbe mentions the idea, but he throws it out as a bare conjecture, and proposes no mode of ascertaining the truth of it He himself acknowledges, that Franklin first entertained the bold thought of bringing lightning from the heavens, by means of pointed rods fixed in the air. The similarity of electricity and lightning is so strong, that we need not be surprised at notice being taken of it, as soon as electrical phenomena became familiar. We find it