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 the 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 22, 1753: "Our friend Franklin will be honored on St. Andrew's Day, the 30th instant, the anniversary of the Royal Society, 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.
"Philadelphia, 28 Mch., 1747.
"To Peter Collinson: