[73] This is most easily observed in large strong sparks taken at some inches distance.
TO J. B. AT BOSTON.
[Observations on the Subjects of the preceding Letter.—Reasons for supposing the Sea to be the grand source of Lightning.—Reasons for doubting this hypothesis.—Improvement in a Globe for raising the Electric Fire.]
Read at the Royal Society, May 27, 1756.
Philadelphia, Jan. 24, 1752.
Sir,
I am glad to learn, by your favour of the 21st past, that Mr. Kinnersley's lectures have been acceptable to the gentlemen of Boston, and are like to prove serviceable to himself.
I thank you for the countenance and encouragement you have so kindly afforded my fellow-citizen.
I send you enclosed an extract of a letter containing the substance of what I observed concerning the communication of magnetism to needles by electricity. The minutes I took at the time of the experiments are mislaid. I am very little acquainted with the nature of magnetism. Dr. Gawin Knight, inventor of the steel magnets, has wrote largely on that subject, but I have not yet had leisure to peruse his writings with the attention necessary to become master of his doctrine.