Electricity experiments reported in the Philosophical Transactions of the Royal Society of London, 1751-1755.

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PHILOSOPHICA.L  TRANSACTICNls,'
[anno 1751.
and conjectures concerning the properties and eiFects of the electrical matter arising from experiments and observations.'
master dying the same year, he again applied to the printing business, and soon after set up a print¬ ing bouse himself. About the same time Mr. F. selected,, and assembled together, a few youths like himself, of a literary and philosophical turn of mind, forming a club or society, to meet on certain days to converse on such subjects, to read books, and to write useful essays. Their collection of books gradually increased, and at length advanced to a public library. The other colonies, sensible of its advantages, began to form similar plans j and hence originated the libraries at Boston, New- York,> Charlestown, &c.; that of Philadelphia having since become equal to any in Europe.
About 1728 or 1729, young Franklin set up a newspaper in Philadelphia, which proved very pro¬ fitable, and otherwise useful, as aftbrding an opportunity of making himself known as a political .writer. He now became a public man; his talents began to be generally known, and in consequence he was appointed successively to the offices of printer to the House of Assembly, clerk to the Gene¬ ral Assembly of Philadelphia, and post-master, and at length a member of the general assembly itself. In 1738 he formed the first fire-company there, to prevent and extinguish fires in houses, &c. alsa insurances from the same j plans which still exist, and were soon imitated by other persons and in other places. In 1744-, during a war between France and England, the French and Indians falling on the back settlements, by Mr. F.'s exertions a body of 10,000 volunteers were raised for their de- '
fence and security.
Pursuits of a different nature next occupied his chief attention for some years. Being always much addicted to the study of natural philosophy; and the discovery of the Leyden experiment in electri¬ city having rendered that science an object of general curiosity} Mr. F. applied himself to it, and greatly distinguished himself in it. By his experiments he made a number of important discoveries, and proposed ingenious theories to account for various phenomena; which have since been generally adopted. His observations he communicated, in a series of letters, to his friend Mr. CoUinson in England, by whom they were published; the first of which is dated March 28, 1747. In these he makes known the power of points in drawing and throwing off" the electric matter, on which he afterwards founded his celebrated method of securing buildings from the stroke and damage of thun¬ der and lightning, having previously proved experimentally the identity of electricity and the matter of lightning : on similar principles too he explained the aurora borealis.
In the year 1749 he proposed a plan of an academy, to be erected in the city of Philadelphia, as a foundation for posterity to found a seminary of learning, more extensive and suitable to future cir¬ cumstances ; and in 1750 three of the schools were opened, viz. the Latin and Greek school, the mathematical school, and the English school. This foundation soon after gave rise to another more extensive college, incorporated by charter in 1755, which is now in a very flourishing condition. In this last year, when he returned to London, he met witli the greatest respect from all learned men: he was elected f.U.S., and had the honour of the Society's gold medal for his philosophical discoveries; he had also the degree of doctor of laws conferred on him by different universities. But at this time, by reason of the war which broke out between England and France, he returned to America, and interested himself in the public affairs of that country, with most efFeclual benefit In 1757 he was again sent to England as agent for the province of Pennsylvania, Massachusetts, Mary¬ land, and Georgia; after remaining here 5 years, he returned to America in 1/62, where he received public thanks for his faithful services. In 17Gi he again returned to England as a provincial agent, where he remained many years. In 1766 he was examined before the House of Commons relative to the state of America, particularly as to the stamp act, which was soon after repealed. But the troubles were now beginning, and the British government seemed resolved to accelerate rather than divert the storm.   Dr. F. remained in Europe till 1775, and then returned to his native country,
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VOL.   XLVII."]
PHILOSOPHICAL   TRANSACTIONS.
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The 4 letters, the last of which contains a new hypothesis for explaining the several phenomena of thunder-gusts, have either in the whole or in part been before communicated to the r. s. It remains therefore now only to lay before the Society an account of the latter part of this treatise, as well as that of a letter intended to be added to it by the author, but which arrived too late for publi¬ cation with it.
This ingenious author, from a variety of well adapted experiments, is of opi¬ nion, that the electrical matter consists of particles extremely subtle, since it can permeate common matter, even the densest metals, with such ease and freedom, as not to receive any perceptible resistance. Electrical matter, according to liim^ differs from common matter in this, that the parts of the latter mutually attract, and those of the former mutually repel each other; hence the divergency in a stream of electrified effluvia: * but that, though the particles of electrical matter do repel each other, they are strongly attracted by all other matter. From these 3 things, viz. the extreme subtilty of the electrical matter, the mutual repulsion of its parts, and the strong attraction between them and other matter, arises this effect, that when a quantity of electrical matter is applied to a mass of common matter of any size or length within our observation (which has not already got
having first endeavoured in vain to dissuade the ministry from their coercive measures. His flima stood as high in the political as it had done in the scientific worid. He became an active nicnibcr of the new legislative assembly, and America is indebted for the fomiatiun of its cDnstiiuLion (u this virtuous and enlightened philosopher. After this important service lie was scat ambassador to France, to negociate an alliance with that country, in which he was completely successful. He also acted as one of the plenipotentiaries for his country in signing the treaty of peace with England in 1783, Two years after, he returned again to America, and received from his grateful countrymen those honours and distinctions which he had so justly merited. At length, after rendering to mankind the mo.st essential benefits as a natural and moral philosopher, the infirmities of age and sedentary employmenti increasing fast upon him, he became more and more afflicted with the gout and the stone, till tlio time of his death, which happened the 17th of April 1790, at 84 years of age. ¦ To record Dr. Franklin's numerous discoveries and experiments, with the many useful institutions founded by his means, and the other curious transactions of his long and valuable life, would require an ample volume: and indeed a posthumous volume has been published, drawn up by himself, but containing only about half the term of his life; which leaves a general wish that the remainder of such interesting memoirs may one day see the light.
Dr. F. was author of very numerous tracts and essays on various branches of natural philosophy, as ¦well as on politics and miscellaneous subjects, which have been published in different forra,s, Hif diction was easy, natural, and flowing; and his conversation at once amusing and instmctive. His temper and manner lively, innocent, playful, interesting. His character leading and persuasive, not commanding. Among his playfellows, while a boy, be was always the captain, leader, and conductor; among men of all descriptions, in maturer age, he was the life and soul of every com¬ pany.
* As the electric stream is observed to diverge very little, when the experiment is made in vacuo, this appearance is more owing to the resistance of the atmosphere, tliat to any natural tendency in tlie electricity itself.   W. W.—Orig.