Benjamin Franklin Papers

Experiments and Observations, [April 1751]

Experiments and Observations, 1751

Experiments and Observations on Electricity, Made at Philadelphia in America, by Mr. Benjamin Franklin, and Communicated in several Letters to Mr. P. Collinson, of London, F.R.S. London: Printed and sold by E. Cave, at St. John’s Gate. 1751. (Yale University Library)

Franklin’s reports on electricity had an immediate and favorable reception in England.9 The first account of his experiments, which he sent to Collinson, May 25, 1747, though not read in the Royal Society, was shown to some of the members, particularly William Watson. Watson, who was the principal English electrician, warmly approved Franklin’s ideas (which he mistakenly believed corresponded with his own),1 and in a paper presented to the Society, January 21, 1748, quoted three pages of Franklin’s letter.2 Subsequent reports from Philadelphia Collinson communicated to the English philosophers in the same way. Franklin’s letters of April 29, 1749, on electricity and thundergusts, addressed respectively to Collinson and Dr. John Mitchell, were read in the Society in the fall of 1749, and were “Deservedly admired not only for the Clear Intelligent Stile, but also for the Novelty of the Subjects.” Franklin’s conjectures that earthquakes are caused by electricity were studied when earthquakes shook London in the spring of 1750, and William Stukeley explained the phenomenon entirely in terms of Franklin’s hypothesis.3 A wider audience learned something of the Philadelphians’ work through the Gentleman’s Magazine. A short résumé of some of their experiments appeared in the January 1750 issue;4 in May the editor printed Franklin’s letter to Collinson on pointed conductors, identifying the author only as “a Gentleman in America, whose ingenious Letters on this Subject will soon be published in a separate Pamphlet.”5

For Franklin’s experiments and observations, though not printed in the Philosophical Transactions, were about to receive wider circulation and, because collected, have a greater impact. In February 1750 Collinson had written that he was collecting Franklin’s letters—five in all—“with Intention to putt them into some Printers Hand to be communicated to the Publick.” In April he reported that they had been given to Edward Cave, publisher of the Gentleman’s Magazine, and were “now on the Press under the Inspection and Correction of our Learned and Ingenious Friend Dr. Fothergill6—for Wee thought it a great Pitty that the Publick should be deprived the benefit of so many Curious Experiments.” After the immemorial manner of printers, Cave was dilatory, and even Collinson grew impatient. In December 1750 Cave reported that the Experiments were in press;7 by February everything was ready except the engraved illustrations. The delay, however, gave Franklin time to make some additions and corrections and to send Collinson still another group of observations to include in the work.8 The pamphlet finally appeared in April 1751. It was entitled Experiments and Observations on Electricity, made at Philadelphia in America, and sold for 2s. 6d.

Enclosing an unfinished copy to a rural physician in Dorset in March, Dr. Fothergill explained that the author was “a Gentleman with whom I have corresponded, and who I think has said more sensible things on the subject, and let us see more into the nature of this delicate affair than all the other writers put together; … This little work … was published under my care, and so far as related to the press, my correction.”9 Joseph Priestley, reviewing the history of electricity fifteen years later, asserted unequivocally, “Nothing was ever written upon the subject of electricity 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.10 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.”1

Fothergill’s “pretty preface,” as Collinson called it, is printed herewith, and below it is a list of the contents of the 1751 edition. The title of each paper is followed in brackets by the pages in Volume iii or iv of the present edition where the text is reprinted, together with any other information required to correct or supplement the heading as first printed. The plate of illustrations included in the 1751 edition is reproduced, facing p. 130.2

The Preface.

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 publick, but were communicated at different times, and most of them in letters wrote on various topicks, as matters 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 contain’d so many curious and interesting particulars relative to this affair, that it would be doing a kind of injustice to the publick, 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 detach’d 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 publick his reflections and experiments on the subject, finish’d with that care and precision, of which the treatise before us shews he is alike studious and capable. He was only apprized of the step that had been thus taken, while the first sheets were in the press, and time enough for him to transmit some farther remarks, together with a few corrections and additions, which are placed at the end, and may be consulted in the perusal.

The experiments which our author relates are most of them peculiar to himself; they are conducted with judgment, and the inferences from them plain and conclusive; though sometimes proposed under the terms of suppositions and conjectures.

And indeed the scene he opens, strikes us with a pleasing astonishment, whilst he conducts us by a train of facts and judicious reflections, to a probable cause of those phaenomena, which are at once the most awful, and, hitherto, accounted for with the least verisimilitude.

He exhibits to our consideration, an invisible, subtile matter, disseminated through all nature in various proportions, equally unobserved, and, whilst all those bodies to which it peculiarly adheres are alike charged with it, inoffensive.

He shews, however, that if an unequal distribution is by any means brought about; if there is a coacervation in one part of space, a less proportion, vacuity, or want, in another; by the near approach of a body capable of conducting the coacervated part to the emptier space, it becomes perhaps the most formidable and irresistible agent in the universe. Animals are in an Instant struck breathless, bodies almost impervious by any force yet known, are perforated, and metals fused by it, in a moment.

From the similar effects of lightening and electricity our author has been led to make some probable conjectures on the cause of the former; and at the same time, to propose some rational experiments in order to secure ourselves, and those things on which its force is often directed, from its pernicious effects; a circumstance of no small importance to the publick, and therefore worthy of the utmost attention.

It has, indeed, been of late the fashion to ascribe every grand or unusual operation of nature, such as lightening and earthquakes, to electricity; not, as one would imagine, from the manner of reasoning on these occasions, that the authors of these schemes have, discovered any connection betwixt the cause and effect, or saw in what manner they were related; but, as it would seem, merely because they were unacquainted with any other agent, of which it could not positively be said the connection was impossible.

But of these, and many other interesting circumstances, the reader will be more satisfactorily informed in the following letters, to which he is therefore referred by

The Editor.


Letter I. To Peter Collinson, July 28, 1747. pp. 1–9. [III, 156–64]

Letter II. To Peter Collinson, Sept. 1, 1747. pp. 10–18. [May 25, 1747. III, 126–35]

Letter III. To Peter Collinson. Farther Experiments and Observations in Electricity. 1748. pp. 19–35. [April 29, 1749. III, 352–65]

Letter IV. Containing Observations and Suppositions, towards forming a new Hypothesis, for explaining the several Phaenomena of Thunder Gusts. [n.d.] pp. 36–49. [To John Mitchell, April 29, 1749. III, 365–77]

Additional Papers. To Peter Collinson, July 29, 1750. p. 50. [IV, 9]

Opinions and Conjectures, Concerning the Properties and Effects of the electrical Matter, arising from Experiments and Observations, made in Philadelphia, 1749. pp. 51–82. [Enclosure in next above, July 29, 1750. IV, 9–34]

Additional Experiment, proving that the Leyden Bottle has no more electric Fire in it when charged, than before; nor less when discharged: … [n.d.] pp. 83–5. [c. Sept. 27, 1750. IV, 65–7]

Corrections and Additions to the Preceding Papers. [n.d.] pp. 85–6. [Incorporated in annotation of the papers in the present edition and not separately reprinted.]

[Note numbering follows the Franklin Papers source.]

9The following account is based in part on Cohen, BF’s Experiments, pp. 77–100. As Cohen makes clear, the facts belie the account BF gave in his autobiography of the Royal Society’s reception of his work: “Oblig’d as we were to Mr. Colinson for his Present of the Tube, &c. I thought it right he should be inform’d 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 for Mr. Kinnersley, on the Sameness of Lightning with Electricity [see above, III, 365] … had been read but was laught at by the Connoisseurs: The Papers however being shown to Dr. Fothergill, he thought them of too much value to be stifled, and advis’d the Printing of them. … It was however some time before those Papers were much taken Notice of in England.” Par. Text edit., p. 382.

1Cohen, BF’s Experiments, pp. 95–100.

2William Watson, “Some further Inquiries into the Nature and Properties of Electricity,” Phil. Trans., XLV (1748), 98–100.

3William Stukeley, “On the Causes of Earthquakes,” ibid., XLVI (1749–50), 643.

4Gent. Mag., XX (1750), 34–5.

5See above, III, 472.

6John Fothergill (1712–1780), son of a well-to-do Yorkshire Quaker farmer who made three religious visits to America; apprenticed to an apothecary at Bradford, 1728; M.D., Edinburgh, 1736; studied two years at St. Thomas’s Hospital, London; began to practice, 1740, first at White Hart Court, London, later at Harpur Street, Red Lion Square. He rose rapidly in his profession, “climbed on the backs of the poor into the pockets of the rich,” and soon had one of the largest and most lucrative practices in England. His Account of the Sore Throat, attended with Ulcers (scarlatina), 1748, which went into six editions, increased his reputation. He attended BF professionally in the fall of 1757.

Profoundly interested in botany, he encouraged John and William Bartram by purchasing plants and drawings, wrote the preface for the London edition of James Logan’s work on the generation of plants, 1747, and befriended a score of young American students of medicine in Britain. The anatomical drawings he gave to the Pennsylvania Hospital, 1762, and his advice to William Shippen, Jr., and John Morgan were invaluable in the founding of the medical department of the College of Philadelphia. An annual allowance of £40 he and some friends made to Joseph Priestley enabled Priestley to continue his experiments in chemistry, 1779.

For many years Fothergill exerted a powerful influence on the Society of Friends in England and America. He analyzed clearly the dilemma of the Quaker majority in the Pennsylvania Assembly, and advised the Quaker members to withdraw, 1756. He proposed schemes to improve the diet, health, and prosperity of the working classes; suggested that scholarships be created in English universities for American students; and dreamed of an international court of justice to settle national conflicts and prevent wars. He gave BF a silver tea pot, 1765, with the engraved motto, “Keep bright the chain.” Of him BF wrote to their mutual friend John C. Lettsom, “I can hardly conceive that a better man has ever existed.” DNB; John C. Lettsom, Some Account of the late John Fothergill, M.D. (London, 1783); R. Hingston Fox, Dr. John Fothergill and his Friends (London, 1919).

7Gent. Mag., XX (1750), 537.

8See above, p. 115.

9Fothergill to William Cuming, March 18, 1751, Richmond, Va., Academy of Medicine, quoted in Betsy C. Corner, “Dr. Fothergill’s Friendship with Benjamin Franklin,” APS Proc., CII (1958), 413.

10No printed translation into Latin has been found nor any manuscript translation to which Priestley could have been referring in this statement of 1767. There is, however, in the Österreichische National-Bibliothek, Vienna, a MS volume containing portions of a Latin translation of either the 1769 or the 1774 edition of Exper. and Obser. in what appears to be the handwriting of BF’s friend Jan Ingenhousz, appointed court physician in Vienna, 1769. Only pp. 46–297 and 373–89 survive of what must have been a considerably longer manuscript. These pages correspond, with a few condensations and minor omissions, to pp. 38–247 and 304–14 of the 1769 English edition.

1The History and Present State of Electricity (London, 1767), p. 159.

2Since the publication of Volume III of this edition, the editors have learned of the existence in the Boston Public Library of a copy of Exper. and Obser., 1751 edit., containing some corrections, mostly in BF’s hand, and bearing his characteristic shelf mark on the inside front cover. See Edwin Wolf, 2d, “A Key to the Identification of Franklin’s Books,” PMHB, LXXX (1956), 407–9. Nearly all the emendations coincide with similar ones in the Yale presentation copy and BF’s own copy in the Yale University Library (see above, III, 118), though there are fewer pen-and-ink notations in it than in the other two corrected copies. The Boston Public Library copy contains a table of contents in BF’s hand and two corrections (apparently in a different hand) not found in either of the copies in the Yale Library; both conform to the text as given in the Bowdoin MS and printed in this edition: I. In the letter to Peter Collinson, May 25, 1747 (above, III, 126), where the date was originally printed incorrectly as “Sept. 1,” the month and day have been struck through and “May 25” inserted above. 2. In the letter to John Mitchell, April 29, 1749, on thundergusts, sec. 44 (above, III, 374), the word “single” is inserted in the margin between “a” and “tree.” The editors are indebted to Mr. John Alden of the Boston Public Library for calling their attention to this volume.

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