Note 15 — William Herschel.
Reading edition
John Michell had been a member of the Royal Society since 1760: he died in 1793. He was a philosophical thinker, as is shown by his memoirs on the distances of the stars, and by his invention of the method for determining the earth's density. It is not certain that he was personally known to Herschel, although his writings were familiar to the latter.
Alexander Wilson was Professor of Astronomy at Glasgow, and is chiefly known to us by his theory of the nature of the solar spots, which was adopted and enlarged by Herschel. He died in 1786; but the families of Wilson and Herschel remained close friends.