Some other important observations made by Kinnersley, who, besides being an intimate friend, was the original associate of Ben. Franklin, are summed up as follows: A coated flask containing boiling water cannot be charged, the electricity passing off with the steam; but when the water gets cold the flask may be charged as usual. A person in a negative state of electricity standing upon an electric, and holding up a long sharp needle out of doors in the dark, observes light upon the point of it. No heat is produced by electrifying a thermometer, nor by passing shocks through large wire, but small wire is heated red-hot, expanded and melted (Phil. Trans. for 1763, Vol. LIII. p. 84; Thomson, “Hist. Roy. Soc.,” p. 445).
In the New York “Electrical Review” of May 13, 1905, will be found the following curious reference to the Boston Art Club exhibits of President R. H. W. Dwight:
“Among these is an interesting broadside, which gives a summary of two lectures on electricity by Ebenezer Kinnersley delivered in Faneuil Hall in September, 1751—the first lectures probably ever delivered on the then new subject of electricity. Kinnersley was an Englishman, who was head master in English literature in the College of Philadelphia, from 1753 to 1773, a student of science, who made a number of discoveries in electricity and invented a number of quaint electrical devices. He and Franklin were on intimate terms, and were closely associated in their electrical experiments. Kinnersley has been erroneously cited as an anticipator of Oersted’s discovery of the deflection of a magnetic needle by an electric current. The former’s experiment, however, was purely electrostatic. In the summary of these two lectures, among other things, it states that electricity ‘is an extremely subtile fluid; that it doth not take up any perceptible time in passing through large portions of space; that it is mixed with the substance of all other fluids and solids of our globe; that our bodies at all times contain enough of it to set a house on fire.’”
The exhibits of President Dwight are:
“An artificial spider animated by the electric fire so as to act like a live one; a shower of sand which rises again as fast as it falls; a leaf of the most mighty of metals suspended in the air, as is said of Mahomet’s tomb; electrified money which scarce anybody will take when offered to them; a curious machine, acting by means of the electric fire, and playing a variety of tunes on eight musical bells.”
This broadside of 1751 appears to antedate any other similar notice of electrical experiments.
The “Electrical Review” of April 23, 1904, p. 621, had published copy of an advertisement from the Massachusetts Gazette of March 7, 1765, giving notice of a course of lectures by David Mason, illustrated by “entertaining experiments on electricity similar to those cited in the broadside under date of 1751.” The advertisement of 1765, here referred to, appears at A.D. 1771.
References.—Sturgeon’s “Lectures,” London, 1842, p. 169; “The Electrical Researches of Hon. Henry Cavendish,” 1879, Nos. 125, 137, 213; Phil. Trans., Vol. LIII. part i. pp. 84–87; Vol. LIV. p. 208; Vol. LXIII, 1773, part i. p. 38; also the Hutton abridgments, Vol. XI. p. 702, and Vol. XIII. p. 370; Bertholon, “Elec. du Corps Humain,” 1786, Vol. I. pp. 23, 33, 214, 217, 220.
A.D. 1762.—Sulzer (Johann Georg), a Swiss philosopher, member of the Berlin Academy of Sciences, in his “Theory of Agreeable and Disagreeable Sensations” (“Theorie d. angenehmen u. unangenehmen Empfindungen,” Berlin, 1762), thus expresses himself: “When two pieces of metal, one of lead and the other of silver, are so joined together that their edges make one surface, a certain sensation will be produced on applying it to the tongue, which comes near to the taste of martial vitriol (vitriol of iron); whereas each piece by itself betrays not the slightest trace of that taste” (F. C. Bakewell, “Manual of Electricity” London, 1857, Chap. III. p. 28).
The passage in the edition “Nouvelle Théorie des Plaisirs,” published in 1767, is thus given by Sabine, “Electric Telegraph,” 1872, p. 15: “On taking two pieces of different metals—silver and zinc—and placing one of them above and the other underneath his tongue, he found that, so long as the metals did not make contact with each other, he felt nothing; but that when the edges were brought together over the tip of his tongue, the moment contact took place and during the time it lasted, he experienced an itching sensation and a taste resembling that of sulphate of iron....” Sulzer does not appear to have been much surprised at the result, thinking it “not improbable that, by the combination of the two metals, a solution of either of them may have taken place, in consequence of which the dissolved particles penetrate into the tongue; or we may conjecture that the combination of these metals occasions a trembling motion in the respective particles, which, exciting the nerves of the tongue, causes that peculiar sensation.”