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which it contained; or, if they could not effect this, they would at least conduct the ftroke to the earth, without any injury to the building.
It was not until the fummer of 1752, that he was enabled to complete his grand and unparalleled discovery by experiment. The plan which he had originally propofed, was, to erect on fome high tower, or other elevated place, a centry-box, from which fhould rise a pointed iron rod, infulated by being fixed in a cake of refin. Electrified clouds paffing over this, would, he conceived, impart to it a portion of their electricity, which would be rendered evident to the fenfes by fparks being emitted, when a key, a knuckle, or other conductor, was prefented to it. Philadelphia at this time afforded no opportunity of trying an experiment of this kind. Whilft Franklin was waiting for the erection of a fpire, it occurred to him, that he might have more ready access to the region of clouds by means of a common kite. He prepared one by attaching two crofs fticks to a filk handkerchief, which would not fuffer fo much from the rain as paper. To his upright stick was affixed an iron point. The ftring was, as ufual, of hemp, except the lower end, which was filk. Where the hempen ftring terminated, a key was faftened. With this apparatus, on the appearance of a thunder-guft approaching, he went out into the commons, accompanied by his fon, to whom alone he communicated his intentions, well knowing the ridicule which, too generally for the intereft of fcience, awaits unfuccefsful experiments in philofophy. He placed himself under a fhed to avoid the rain. His kite was raifed. A thunder cloud paffed over it. No fign of electricity appeared. He almost despaired of fuccefs; when fuddenly he obferved the loofe fibres of his string to move towards
towards an erect pofition. He now prefented his knuckle to the key, and received a strong spark. How exquifite muft his fenfations have been at this moment! On this experiment depended the fate of his theory. If he fucceeded, his name would rank high amongst those who have improved fcience; if he failed, he must inevitably be fubjected to the derifion of mankind, or, what is worse, their pity, as a well-meaning man, but a weak, filly projector. The anxiety with which he looked for the refult of his experiment, may eafily be conceived. Doubts and despair had begun to prevail, when the fact was afcertained in fo clear a manner, that even the most incredulous could no longer withhold their affent. Repeated fparks were drawn from the key, a phial was charged, a fhock given, and all the experiments made, which are ufually performed with electricity.
About a month before this period, fome ingenious Frenchmen had completed the discovery, in the manner originally proposed by Dr. Franklin. The letters which he fent to Mr. Collinfon, it is faid, were refufed a place amongst the papers of the Royal Society of London. However this may be, Collinfon published them in a separate volume, under the title of New Experiments and Obfervations on Electricity, made at Philadelphia, in America. They were read with avidity, and foon tranflated into different languages. A very incorrect French tranflation fell into the hands of the celebrated Buffon, who, notwithstanding the difadvantages under which the work laboured, was much pleased with it, and repeated the experiments with fuccefs. He prevailed upon his friend, M. D'Alibard, to give to his countrymen a more correct tranflation of the work of the American electrician. This contributed much
towards fpreading a knowledge of Franklin's principles in France. The King, Louis XV. hearing of thefe experiments, expreffed a wish to be a fpectator of them. A courfe of experiments was given at the feat of the Duc D'Ayen, at St. Germain, by M. De Lor. The applaufes which the King beftowed upon Franklin, excited in Buffon, D'Alibard, and, De Lor, an earnest defire of afcertaining the truth of his theory of thunder-gufts. Buffon erected his apparatus on the tower of Montbar, M D'Alibard at Mary-laville, and De Lor at his houfe in the Eftrapade at Paris, fome of the higheft ground in that capital. D'Alibard's machine firft fhewed figns of electricity. On the 10th of May, 1752, a thundercloud paffed over it, in the abfence of M. D'Alibard; and a number of fparks 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-la-ville. 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 fuccefsful with the apparatus erected at his own house. These difcoveries foon excited the philofophers of other parts of Europe to repeat the experiment. Amongst thefe, none fignalized themselves more than Father Beccaria cf Turin, to whofe obfervations fcience is much indebted. Even the cold regions of Ruffia were penetrated by the ardor for difcovery. Profeffor Richman bade fair to add much to the ftock of knowledge on this fubject, when an unfortunate flafh from his rod put a period to his exiftence. The friends of fcience will long remember with regret the amiable martyr to electricity.
By thefe experiments Franklin's theory was eftablished in the moft 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 obfcure city of Philadelphia, the name of which was hardly known, fhould be able to make difcoveries, and to frame theories, which had efcaped the notice of the enlightened philofophers of Europe, was too mortifying to be admitted. He muft certainly have taken the idea from fome one else. An American, a being of an inferior order, make difcoveries! Impoffible. It was faid, that the Abbé Nollet, in 1748, had fuggefted the idea of the fimilarity of lightning and electricity, in his Leçons de Phyfique. It is true, that the Abbé mentions the idea, but he throws it out as a bare conjecture, and propofes no mode of afcertaining the truth of it. He himfelf acknowledges, that Franklin firft entertained the bold thought of bringing lightning from the heavens, by means of pointed rods fixed in the air. The fimilarity of electricity and lightning is fo ftrong, that we need not be furprifed at notice being taken of it, as foon as electrical phenomena became familiar. We find it mentioned by Dr. Wall and Mr. Grey, while the science was in its infancy. But the honour of forming a regular theory of thunder-gufts, of fuggefting a mode of determining the truth of it by experiments, and of putting thefe experiments in practice, and thus establishing his theory upon a firm and folid bafis, is inconteftibly due to Franklin. D'Alibard, who made the firft experiments in France, fays, that he only followed the track which Franklin had pointed out.
It has been of late afferted, that the honour of completing the experiment with the electrical
kite, does not belong to Franklin. Some late English paragraphs have attributed it to fome Frenchman, whofe name they do not mention; and the Abbé Bertholon gives it to M. De Romas, affeffor to the prefideal of Nerac; the English paragraphs probably refer to the fame perfon. But a very light attention will convince us of the injuftice of this procedure: Dr. Franklin's experiment was made in June 1752; and his letter, giving an account of it, is dated October 19, 1752. M. De Romas made his first attempt on the 14th of May 1753, but was not fuccefsful until the 7th of June; a year after Franklin had completed the discovery, and when it was known to all the philofophers in Europe.
Befides these great principles, Franklin's letters on electricity contain a number of facts and hints, which have contributed greatly towards reducing this branch of knowledge to a science. His friend, Mr. Kinnerfley, communicated to him a discovery of the different kinds of electricity excited by rubbing glafs and fulphur. This, we have faid, was firft obferved by M. Du Faye; but it was for many years neglected. The philofophers were difpofed to account for the phenomena, rather from a difference in the quantity of electricity collected; and even Du Faye himfelf feems at last to have adopted this doctrine. Franklin at first entertained the fame idea; but upon repeating the experiments, he perceived that Mr. Kinnerfley was right; and that the vitreous and refinous electricity of Du Faye were nothing more than the pofitive and negative states which he had before obferved; that the glass globe charged pofitively, or increased the quantity of electricity on the prime conductor, whilft the globe of fulphur diminished its natural quantity, or charged negatively. Thefe experiments and obfervations