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Would, he conceived, impart to it a portion of theii eiectricitj, which would be rendered evident to Ilia •eases by sparks being emitted, when a key, the knuckle, or other conductor, was presented to it. Philadelphia at this time afforded no opportunity of trying an experiment of this kind. While Franklin was waiting for the erection of a spire, 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 fastening two cross sticks to a silk handkerchief, which would not suffer so much from the rain as paper. To the upright stick was affixed 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 thundcrgust approaching, he went out 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 shade, to avoid the rain—his kite was raised—a thunder-cloud passed over it—no sign of electricity appeared. He almost despaired of success, when, suddenly, he observed the loose fibres of his string to 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 among those who had improved science; if he failed, he must inevitably be subjected to the derision of mankind, or, what is worse, theirity, as a well-meaning man, but a weak, silly projector. The anxiety with which he looked for the result of his experiment, may be easily 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 theirasscut. Repeated sparks were drawn from the key, a phial was charged, a shock given, and all the experiments made which are usually performed with electricity.
About a month before this period, some ingenious Frenchman had completed the discovery in the man- tier originallv proposed by Dr. Franklin. The letters which fie seiit to Mr. Collinson, it is said, were refused a place in the Transactions of the Royal Society of London. However this may be, Collinson published them in a separate volume, under the title of "New Experiments and Observations on Electricity, made at Philadelphia, in America." They were read with avidity, and soon translated into different languages. A very incorrect French translation fell into the hands of the celebrated Buffnn, who,. notwithstanding the disadvantages under which the work laboured, was much pleased with it, and repeated the experiments with success. He prevailed on his friend, M. D'Aboard, to give his countrymen a more correct translation of the works 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 Due D'Ayen, at St. Germain, 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 thundergust Buifon erected his ap
Raratus on the tower of Montbar, M, D'Alibard at Mary-la-ville, and De Lor at his house in the Eslrapadeal Paris, some of the highest ground in that capital. D'Alibard's machine first showed signs of electricity. On the 10th of May, I7.i2, a tr.umler-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-lavHle. An account of this experiment was given to the Royal Academy of Sciences, by M. D'Alibard, in a Memoir, dated May I3th, I752. 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, among wnom, 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 ardour fbf 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 va', nitv 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 philosophersof 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 Abbe Nollet, 1748, had suggested the idea of the similarity of lightning and electricity in his iecons dc 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 hea> veris, 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 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 thundergusts, of suggesting a mode of determining the truth of it by experiments, and of putting these experiments in practice, and thus establishing the theory upon a firm and solid basis, i hcon'.estibly due to Franklin. D'Alibard, who mad, Ihe first experiments in France, says, that he only followed the tract which Franklin had pointed out.
It has been of late asserted, that the honour 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 tie Abbe Bertholon gives it to M. de Romas, assessor to the presideal of Nerac • flic 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 experiment was made in June, I752; and his letter, giving an account of it, is dated October 19,I753. M.ide 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 philosophern Europe.
Besides 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. Kinners ley 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 electricity 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 conduotor, whili the globe of sulphur diminished its natural quantity, or charged negatively. These experiments and obser. rations opened anew field for investigation, upon which electricians entered with avidity; and their la^ tiours have added much to the stock of our knowledge.
In September, 1752, Franklin entered upon a course of 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 thunder-strokes, it is the earth that strike* 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 dale, aad has been attributed to the Abbe 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' teen adopted. Some opposition was made to his theories, particularly by the Abbe Nollet, who was, however, but feebly supported, while the first philoso
fihers in Europe stepped forth in defence of Franklin's principles, amongst whomD'Alibard and linecaria 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 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 beled 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 mvented Pennsylvama fire-places; in which he minutely and accurately states the advantages of different kinds of fire-places; and endeavours to show, that the one which he describes is to be preferred to any other. This contrivance has given list