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would, ho conceived, impart to it a portion of their electricity, which would be rendered evident to thio senses by sparks being emitted, when a key, the knucklo, or other conductor, was presented to it. Philadelphia at this time afforded no opportunity of trying an ex. periment 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 mea.is of a common kite. He prepared one by fastening two cross sticks to a silk handkerchief, which would not suffer so much froin the rain as paper. To the upright stick was affixed an iron point. The string was, as usual, of heinp, except the lower end, which was silk. Where the hempen string terminated, a key was fastened. With this apparatus, on the appear. ance of a thundergust approaching, he went out into the commons, accompanied by his son, to whoni alono he communicated his intentions, well knowing the ridicule which, too generally for the interest of science, awaits unsuccessful experiments in philosophy. He placed hiinseis 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 louse fibres of bis string to move towards ali ercct 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 namo 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, their pity, 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 ascer. tained in so clear a manner, that even the most incrodulous could no longer withhold their assent. 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 Erenchman had completed the discovery in the mam
ner originally proposed by Dr. Franklin. The letters which he sent 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 Buffon, who,.notwithstanding the disadvantages under which the work laboured, was much pleased with it, and repeated the experiments with ccess. He
prevailed on his friend, M. D'Alibard, to give his countrymen a niore 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 thein. A course of experiments was given at the scat of the Duc D'Ayen, at St. Germain, hy M. de Lor. The applauses vhich 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. Buffon erected his apparatus on the tower of Moutbar, M. D'Alibard at Mary-la-ville, and De Lor at his house in the Estra. pade at Paris, some of the highest ground in that capi. tal. D’Alibard's machine first showed signs of electricity. On the 10th of May, 1732, a thunder-cloud passed over it, in the absence of M. D'Alihard, and a number of sparks were drawn from it by Coiffier, a joiner, with whom D’Alijard had left directions how to proceert, and by M. Raulet, the prior of Mary-laville. An account of this experiment was given to the Royal Acader.y 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 appara. tus erected at his own house. These philosophers soon excited those of other parts of Europe to repeat the experiment, among whom, none signalized themBelves more than Father Beccaria, of Turin, to whoso observations science is much indebted. Even the cold regiors of Russia were penetrated by the ardour fou
discovery. Professor Richman bade fair to add much to the stock of knowledge on this subject, when an unfortunate flash fiom his conductor put a period to bis existence. The friends of science will long re. member with regret, the amiable martyr to electricity. · By these experiments Franklin's theory was estab lished in the most convincing manner. When the truth of it could no longer be doubled, envy and var nity endeavoured to detraut from its merit. That an Asnerican, an inhabitant of the obscure city of Phila delphia, 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 phj. losophers of Europe, was too mortifying to be adinit. ted. 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 bis Lem cons 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 thb bold thouglit os bringing lightning from the hear velis, by ineans 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 fainiliar. We find it mentioned by Dr. Wal; 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 experinients, and of putting these experiments in practice, and thus es ablishing the theory upon a firm and solid basis, i ocontestibly due to Franklin. D'Alibard, whu inad, the first experiraents in France, says, that ku only for lowed the tract which Franklin had pointed out.
It has been of lute asserted, that the honour of com pleting the experiment with the electrical kite, does not belong 10 Franklin. Some late English paragiaphy have attributed it to some Frenchman, whose name they do not mention; and the Abbè Bertholon gives is, to M. de Romas, assessor to the presideal of Nerac.
the English paragraphs probably refer to the same person. But a very slight attention will convinco ug of the injustice 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 successful until the 7th of June, a year after Franklin had completed the dis overy, and when it was known to all the philosopher n Europe.
Besides these great principles, Franklin's letters on electricity contain a number of facts and hints, whick have contributed greatly towards reducing this branch of knowledge to a science. His friend Mr. Kinners ley communicared to himn a discovery of the different kinds of electricity, excited by rubbing glass and solphur. This, we have said, was first observed by M. du Faye; but it was for many years neglected. Tiro philosophers were disposed to account for the pheno mena, rather from a difference in the quantity of electricity collected, and even Du Faye himself seems at 'ast 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 ne. gative 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 negatively. These experiments and obser. vations opened a new field for investigation, upod which electricians entered with avidity; and their la Bours bave 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 form ed this conclusion :-" That live clouds of a thundergust are most cominonly in a negative state of electricity, but sometimes in a positive state;" and from this it follows, as a necessary consequence, “ that, for the nost part, in thunder-strokes, it is the earth that strikos
Into the clouds, and not the clouds that strike into the earth." The letter containing these observations is dated in Septen:bcr, 1753; and yet the discovery of ascending thunder has been said to be of a modern date, aad has been attributed to the Abbé Bertholon, who published his memoir on the subject in 1776.
Franklin's letters have been translated into mosi of the European languages, and into Latin. In proporion as they have become known, his principles liave been adopted. Some opposition was made to his theories, particularly by the Athé Nollet, who was, liowever but feebly supported, while the first philosophers in Europe stepped forth in defence of Frank. lin's principles, amongst whom D’Alibard and Lec. caria were the most distinguished. The oppsition has gradually ceased, and the Franklinian systein is now universally adopted, where science flourishes.
The important practical use which Franklin made of his discoveries, the securing of houses from injury by lightniny, has been already mentioned. Pointed coudictors are now very conmon in America ; but prejudice has hitherto prevented their general introduction into Europe, notwithstanding the inost undoubted proofs of their utility have been given. Bus 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 heen adeli. ed in so inany places, than that it lias not universally prevailed. It is only by degrees that the great body of mankind can be led into new practices, how. ever 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 rendler it so.
In the year 1745, Franklin published an account of his new invented Pennsylvania 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 proferred to any other. This contrivance has given vise