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XLIII: TO PETER COLLINSON - Benjamin Franklin, The Works of Benjamin Franklin, Vol. II Letters and Misc. Writings 1735-1753 [1904]

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The Works of Benjamin Franklin, including the Private as well as the Official and Scientific Correspondence, together with the Unmutilated and Correct Version of the Autobiography, compiled and edited by John Bigelow (New York: G.P. Putnam’s Sons, 1904). The Federal Edition in 12 volumes. Vol. II (Letters and Misc. Writings 1735-1753).

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XLIII

TO PETER COLLINSON

Philadelphia, 28 March, 1747.

Sir:—

Your kind present of an electric tube, with directions for using it, has put several of us on making electrical experiments, in which we have observed some particular phenomena that we look upon to be new. I shall therefore communicate them to you, in my next, though possibly they may not be new to you, as among the numbers daily employed in those experiments on your side of the water, it is probable some one or other has hit upon the same observations. For my own part, I never was before engaged in any study that so totally engrossed my attention and my time, as this has lately done; for what with making experiments when I can be alone, and repeating them to my friends and acquaintance, who, from the novelty of the thing, come continually in crowds to see them, I have, during some months past, had little leisure for any thing else.

I am, &c.,

B. Franklin.

While on a visit to Boston, in 1746, Franklin witnessed some electrical experiments performed by a Mr. Spence, recently arrived from Scotland. Shortly after his return to Philadelphia the Library Company received from Mr. Collinson, of London, and a member of the Royal Society, a glass tube, with instructions for making experiments with it. With this tube Franklin began a course of experiments which resulted in discoveries which, humanly speaking, seem to be exerting a larger material influence upon the industries of the world than any other discovery of the human intellect. Dr. Stuber, then a resident of Philadelphia, and author of the first continuation of Franklin’s life, who seems to have enjoyed peculiar opportunities of obtaining full and authentic information upon the subject, gives us the following account of the observations which this letter brought for the first time to the notice of the world through Mr. Collinson.

“His observations,” says Dr. Stuber, “he communicated, in a series of letters, to his friend Collinson, the first of which is dated March 28th, 1747. In these he shows 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 honor of this without hesitation; although the English have claimed it for their countryman, Dr. Watson. Watson’s paper is dated January 21st, 1748; Franklin’s, July 11th, 1747, several months prior. Shortly after, 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 showed clearly that when charged the bottle 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, by means of sharp-pointed iron rods raised into the region of the clouds. Even in this uncertain state, his passion to be useful to mankind displayed 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 fires silently and imperceptibly, he suggested the idea of securing houses, ships, etc., 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 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 thunder-gust 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 shed, 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, 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 ascertained, in so clear a manner, that even the most incredulous 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 Frenchman had completed the discovery in the manner 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 labored, was much pleased with it, and repeated the experiments with success. He prevailed on his friend, M. Dalibard, 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 the Fifteenth, hearing of these experiments, expressed a wish to be a spectator of them. A course of experiments was given at the seat of the Duc D’Ayen, at St. Germain, by M. de Lor. The applauses which the King bestowed upon Franklin excited in Buffon, Dalibard, and De Lor an earnest desire of ascertaining the truth of his theory of thunder-gusts. Buffon erected his apparatus on the tower of Montbar, M. Dalibard at Marly-la-ville, and De Lor at his house in the Estrapade at Paris, some of the highest ground in that capital. Dalibard’s machine first showed signs of electricity. On the 10th of May, 1752, a thunder-cloud passed over it, in the absence of M. Dalibard, and a number of sparks were drawn from it by Coiffier, joiner, with whom Dalibard had left directions how to proceed, and by M. Raulet, the prior of Marly-la-ville.

An account of this experiment was given to the Royal Academy of Sciences, by M. Dalibard, 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 Richmann 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.

By these experiments Franklin’s theory was established in the most convincing manner.

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. 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 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 conductor, while the globe of sulphur diminished its natural quantity, or charged negatively. 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.

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.”

In speaking of the first publication of his papers on electricity, Franklin himself says: “Obliged as we were to Mr. Collinson for the present of the tube, &c., I thought it right he should be informed of our success in using it, and wrote him several letters containing accounts of our experiments. He got them read in the Royal Society, where they were not at first thought worth so much notice as to be printed in their Transactions. One paper, which I wrote to Mr. Kinnersley, on the sameness of lightning with electricity, I sent to Mr. Mitchel, an acquaintance of mine, and one of the members also of that Society, who wrote me word that it had been read but was laughed at by the connoisseurs. The papers, however, being shown to Dr. Fothergill, he thought them of too much value to be stifled, and advised the printing of them. Mr. Collinson then gave them to Cave for publication in his Gentleman’s Magazine, but he chose to print them separately in a pamphlet, and Dr. Fothergill wrote the preface. Cave, it seems, judged rightly for his profession, for by the additions that arrived afterwards they swelled to a quarto volume, which has had five editions, and cost him nothing for copy-money.”

The following is an extract from the Preface to the first edition of the pamphlet published by Cave, as above mentioned.

“It may be necessary to acquaint the reader that the following observations and experiments were not drawn up with a view to their being made public, but were communicated at different times, and most of them in letters, written on various topics, as matter only of private amusement.

But some persons to whom they were read, and who had themselves been conversant in electrical disquisitions, were of opinion they contained so many curious and interesting particulars relative to this affair, that it would be doing a kind of injustice to the public to confine them solely to the limits of a private acquaintance.

The editor was therefore prevailed upon to commit such extracts of letters and other detached pieces as were in his hands to the press, without waiting for the ingenious author’s permission so to do; and this was done with the less hesitation, as it was apprehended the author’s engagements in other affairs would scarce afford him leisure to give the public his reflections and experiments on the subject, finished with that care and precision of which the treatise before us shows he is alike studious and capable.”

Dr. Priestley, in his History of Electricity, published in the year 1767, gives a full account of Franklin’s experiments and discoveries.

“Nothing was ever written upon the subject of electricity,” he says, “which was more generally read and admired in all parts of Europe, than these 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 of them 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.

Though the English have not been backward in acknowledging the great merit of this 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 terms Franklinism, Franklinist, and the Franklinian system, occur in almost every page. In consequence of this, Dr. Franklin’s principles bid fair to be handed down to posterity as equally expressive of the true principles of electricity, as the Newtonian philosophy is of the system of nature in general.”

The observations and theories of Franklin met with high favor in France, where his experiments were repeated and the results verified to the admiration of the scientific world. In the year 1753, his friend, Peter Collinson, wrote to him from London: “The King of France strictly commands the Abbé Mazéas to write a letter in the politest terms to the Royal Society, to return the King’s thanks and compliments, in an express manner, to Mr. Franklin of Pennsylvania, for his useful discoveries in electricity, and the application of pointed rods to prevent the terrible effect of thunder-storms.” And the same Mr. Collinson wrote as follows to the Reverend Jared Eliot, of Connecticut, in a letter dated London, November 22d, 1753: “Our friend Franklin will be honored on St. Andrew’s day, the 30th instant, the anniversary of the Royal Soicety, when the Right Honorable the Earl of Macclesfield will make an oration on Mr. Franklin’s new discoveries in electricity, and, as a reward and encouragement, will bestow on him a gold medal.” This ceremony accordingly took place, and the medal was conferred.