William Herschel

“ Hence, from the annexed figure (see Tab. I. fig. 6.) in which A, B, represents a parallel of declination, we may conclude, that the comet was nearly in the same meridian with the star a; but more north than it by an interval equal to the distance of the small star b from a. This will consequently give us a pretty good opportunity to ascertain the comet's place with some accuracy. ”