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at the tops of the masts, and thunder clouds might burst near them, and exert their dreadful effects [1]. That even artificial electricity, when in too great a quantity, and hurried on too fast through a fine iron wire has a remarkable effect upon the wire, appears from a very curious experiment of Mr. Kinnersley of Pensylvania. This gentleman in the presence of Dr. Franklin, by his case of bottles beeing electrified fully, and made to explode at once, after the manner of the experiment of Leyden, through a fine iron wire, the wire appeared at first red hot, and then fell into drops, which burned themselves into the surface of his table or floor. These drops cool in a spherical figure, like very small shot, of which Dr. Franklin transmitted some hither to Mr. Canton [2], who has repeated this experiment. This proves the fusion to have been very compleat, as nothing less than the most perfect fluidity could give this figure to melted iron. These effects from artificial lightning, are exactly similar to those of the natural; as we have several times known iron wires,
- ↑ See more upon this subject Phil. Trans. Vol. XLVIII. page 215.
- ↑ The diameter of a piece of M. Kinnersley's wire, which I received from Doctor Franklin, was one part in 182 of an inch. Artificial lightning from a case of 35 bottles, I find will entirely destroy brass wire of one part in 330 of an inch. At the time of the stroke, a great number of sparks, like those from a flint and steel, fly upwards, and laterally from the place where the wire was laid, and lose their light in the daytime at the distance of about two or three inches. After the explosion, a mark appears on the table the whole length of the wire; and some very small round particles of brass may be discovered, by a magnifier, near the mark; but no part of the wire itself can be found. J. Canton.
