Page:Sir William Herschel, his life and works (1881).djvu/166

144 by himself, fully settled the fact that only four satellites of this planet existed. In 1874 I examined the observations of on his supposed "interior" satellite, thinking that it might be possible that among the very few glimpses of it which he recorded, some might have belonged to Ariel and some to Umbriel, and that by combining rare and almost accidental observations of two satellites which really existed, he had come to announce the existence of an "interior" satellite which had no existence in fact. Such I believe to be the case. In 1801, April 17, describes an interior satellite in the position angle 189°, distant 18″ from the planet. At that instant Umbriel one of Mr. Lassell's satellites, was in the position 191°, and distant 21″ from Uranus, in the most favorable position for seeing it. The observation of 1794, March 27, may belong to Ariel. At the best the investigation is of passing interest only, and has nothing to do with the question of the discovery of the satellites. discovered the two brighter ones, and it was