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Franklin, excited in Buffon, D'Alibard, and De Lor, an earnest desire of ascertaining the truth of this theory of thundergust. 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 10th 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-la-ville. An account of th's experiment was given to the Royal Academy of Sciences, by M. D'Alibard, in a Memoir, dated May 13th, 1752. On the 18th of May, M. de Lor proved equally successful with the apparatus erected at his own house. These philosophers soon excited those of other parts of Europe to repeat the experiment, amongst whom 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 conductor put a period to his existence. The friends of science will long remember with regret, the amiable martyr to electricity.

By these experiments, Franklin's theory was established in the most convincing manner. When the truth of it could no longer be doubted, envy and vanity endeavored 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 some one else. An American, a being of an inferior order, make discoveries! -Impossible. It was said that the Abbé Nollet, 1748, had suggested the idea of the similarity of lightning and electricity in his Legons de Physique. It is true that the Abbé 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 lightning and electricity is so strong, that we need not be surprised at notice being taken of it, as soon as electrica. phenomena became familiar. We find it mentioned by Dr.

Wall and Mr. Grey, while the science was in its infancy But the honor of forming a regular theory of thundergusts, of suggesting a mode of determining the truth of it by experi ments, and of putting these experiments in practice, and thus establishing the theory upon a firm and solid basis, is incontestably due to Franklin.-D'Alibard, who made the first experiments in France, says, that he only followed the track which Franklin had pointed out.

It has been of late asserted, that the honor of completing the experiment with the electrical kite, does not belong to Franklin. Some late English paragraphs have attributed it to some Frenchman, whose name they do not mention; and the Abbé Bertholon gives it to M. de Romas, assessor to the presidal of Nerac: the English paragraphs probably refer to the same person. But a very slight attention will convince us of the injustice of this procedure: Dr. Franklin's experi ment 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 successful until the 7th of June; a year after Franklin had completed the discovery, and when it was known to all the philosophers in Europe.

Besides these great principles, Franklin's letters on elec tricity contain a number of facts and hints, which have contributed greatly towards reducing this branch of knowledge to a science. His friend, Mr. Kinnersley, communicated to him a discovery of the different kinds of electricity, excited by rubbing glass and sulphur. This, we have said, was first observed by M. du Faye; but it was for many years neglected. The philosophers were disposed to account for the phenomena, rather from a difference in the quantity of elec tricity collected, and even du Faye himself, seems at last to have adopted this doctrine. Franklin at first entertained the same idea; but, upon repeating the experiments, he perceived that Mr. Kinnersley was right; and that the vitreous and resinous electricity of du Faye were nothing more than the positive and negative states which he had before observed; and that the glass globe charged positively, or increased the quantity of electricity on the prime conductor, while the globe of sulphur diminished its natural quantity, or charged nega tively. These experiments and observations opened a new field for investigation, upon which electricians entered with avidity; and their labors have added much to the stock of our knowledge.

In September, 1752, Franklin entered upon a course of

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experiments, to determine the state of electricity in the clouds. From a number of experiments he formed this conclusion :-That the clouds of a thundergust are most commonly in a negative state of electricity, but sometimes in a positive state;' and from this it follows, as a necessary consequence, that, for the most part, in thunderstrokes, it is the earth that strikes into the clouds, and not the clouds that strike into the earth.' The letter containing these observations is dated in September, 1753; and yet the discovery of ascending thunder has been said to be of a modern date, and has been attributed to the Abbé Bertholon, who published his memoir on the subject in 1776.

Franklin's letters have been translated into most of the European languages, and into Latin. In proportion as they have become known, his principles have been adopted. Some opposition was made to his theories, particularly by the Abbé Nollet, who was, however, but feebly supported, while the first philosophers in Europe stepped forth in defence of Franklin's principles, amongst whom D'Alibard and Beccaria were the most distinguished. The opposition has gradually ceased, and the Franklinian system is now universally adopted, where science flourishes.

The important practical use which Franklin made of his discoveries, the securing of houses from injury by lightning, has been already mentioned. Pointed conductors are now very common in America; but prejudice has hitherto prevented their general introduction into Europe, notwithstanding the most undoubted proofs of their utility have been given. But mankind can with difficulty be brought to lay aside established practices, or to adopt new ones. And perhaps we have more reason to be surprised that a practice, however rational, which was proposed about forty years ago, should in that time have been adopted in so many places, than that it has not universally prevailed. It is only by degrees that the great body of mankind can be led into new practices, however salutary their tendency. It is now nearly eighty years since inoculation was introduced into Europe and America; and it is so far from being general at present, that it will require one or two centuries to render it so.

In the year 1745, Franklin published an account of his new invented Pennsylvania fireplaces, in which he minutely and accurately states the advantages of different kinds of fireplaces; and endeavors to show, that the one which he describes is to be preferred to any other. This contrivance has given rise to the open stoves now in general use, which,

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