colonies, and detained it, with a fleet of merchant-ships, in the neighbourhood of Sandy-hook, all the summer of 1756; until Fort George, on the frontiers of New York, was taken by the French and Indians, and the whole of the back-settlements thrown into alarm. Nor was his conduct without suspicion, as to avaricious motives. He perplexed all the mercantile pursuits of the middle states, during the summer, by laying an embargo on the export of provisions from all the principal forts, ostensibly to prevent the enemy from obtaining supplies, but really, as it was thought, to lower the price of provisions for the benefit of the contractors, in whose profits he had a share. Franklin designates his whole operations in 1756 as "frivolous, expensive, and disgraceful, beyond conception.'

We are now arrived at a period of Franklin's life, in which it appears proper to enter more fully into his philosophical attainments and discoveries. He modestly dismisses them with a very brief notice in his personal narrative; but they had even at this period attained some notoriety in Europe, and no single name was so largely connected as our author's, at last, with the diffusion of the modern taste for electricity. Dr Priestley says, in his history of that science, that "nothing was ever written upon the subject of electricity, which was more generally read, and admired in all parts of Europe than Franklin's letters. There is hardly any European language into which they have not been translated; and, as if this were not sufficient to make them properly known, a translation has lately been made into Latin. It is not easy to say whether we are most pleased with the simplicity and perspicuity with which these letters are written, the modesty with which the author proposes every hypothesis of his own, or the noble frankness with which he relates his mistakes, when they were corrected by subsequent experiments.

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Though the English have not been backward in acknowledging the merit of the philosopher, he has

had the singular good fortune to be perhaps even more celebrated abroad than at home; so that to form a just idea of the great and deserved reputation of Dr Franklin, we must read the foreign publications on the subject of electricity, in many of which the term Franklinism, Franklinist, and the Franklinian system, occur almost in every page. In consequence of this, Dr Franklin's bids fair to be handed down to posterity, being equally expressive of the true principles of electricity, as the Newtonian philosophy is of the true system of nature in general."

These letters were addressed to his friend Collinson, of whom we have already spoken, and were in fact, in the first instance, a simple report of the success of Franklin and his friends in the use of that gentleman's present of electrical instruments. Finding them acceptable to his friend, and that Dr Fothergill, and some other English philosophers, had permitted the printing of them in the mother-country, until what were called the Philadelphian experiments came to be known in Paris, Franklin was encouraged to continue the correspondence. According to the well known compliment paid him afterwards by M.Turgot,* he seems to have been the first person who discovered the affinity between lightning and electricity, which he suggested in an essay written for a neighbour in Philadelphia who established public lectures in that science. This paper he forwarded to England in 1753; but Dr Stuber, Franklin's townsman, and one of his best biographers, has so well vindicated his fame on this subject from some attacks, and digested so complete a narrative of the interest excited both in France and England on this subject, that, at the hazard of some slight repetitions, we shall transcribe that narrative entire :

"Of all the branches of experimental philosophy, electricity had been least explored. The attractive power of amber is mentioned by Theophrastus and Pliny, and from them by later naturalists. In the

ERIPUIT COLO FULMEN, SCEPTRUMQUE TYRANNIS.

year 1600, Gilbert, an English physician, enlarged considerably the catalogue of substances which have the property of attracting light bodies. Boyle, Otto Guericke, a burgomaster of Magdeburg, celebrated as the inventor of the air-pump, Dr Wall, and sir Isaac Newton, added some facts. Guericke first observed the repulsive power of electricity, and the light and noise produced by it. In 1709, Hawkesbec communicated some important observations and experiments to the world. For several years electricity was entirely neglected, until Mr Grey applied himself to it, in 1728, with great assiduity. He, and his friend Mr Wheeler, made a great variety of experiments; in which they demonstrated, that electricity may be communicated from one body to another, even without being in contact, and in this way may be conducted to a great distance. Mr Grey afterwards found that, by suspending rods of iron by silk or hair lines, and bringing an excited tube under them, sparks might be drawn, and a light perceived at the extremities in the dark. M. du Faye, intendant of the French king's gardens, made a number of experi`ments, which added not a little to the science. He made the discovery of two kinds of electricity, which he called vitreous and resinous; the former produced by rubbing glass, the latter from excited sulphur, sealing-wax, &c. But this idea he afterwards gave up as erroneous. Between the years 1739 and 1742, Desauguliers made a number of experiments, but added little of importance. He first used the terms conductors and electrics per se. In 1742, several ingenious Germans engaged in this subject; of these the principal were, professor Boze of Wittemberg, 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 the electric fluid, 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 28, 1747. In these he shews 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 afterwards Franklin, from his principles of the 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 shewed clearly, that the bottle, when charged, contained no more electricity than before, but that as much was taken from one side as was thrown on the other; and that, to discharge it, nothing was necessary but to produce 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 thunder-gusts, and of the aurora borealis, upon electrical principles. He points out many particulars in which lightning and electricity agree; and he adduces many facts, and reasonings from 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 lightning with 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 suggested the idea of securing houses, ships, &c. from being damaged by lightning, by erecting pointed rods that 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 electric matter 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 originally proposed was, to erect on some high tower, or other elevated place, a sentry-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 evident to the senses by sparks being emitted, when a key, the knuckle, or other conductor, was presented to it. Philadelphia at this time afforded no opportunity of