Previous to the invention of the telescope, spots had been more than once seen on the sun's disc with the unassisted eye. But even if these were of the same character as those which Galileo and others observed, we cannot consider them as anticipations of their discovery by the telescope. As the telescope was now in the possession of several astronomers, Galileo began to have many rivals in discovery; and it is now placed beyond the reach of doubt, that he was not the first discoverer of the solar spots. From the communication which I received from the late Dr. Robertson, of Oxford[13], it appears that Thomas Harriot had discovered the solar spots on or before the 8th of December, 1610. His manuscripts, in lord Egremont's possession, incontestably prove that his regular observations on the spots commenced on the 8th of December, 1610,--at least three months before Galileo discovered them; and that they were continued till the 18th of January, 1613. The observations which he has recorded are 199 in number; and the accounts of them are accompanied with rough drawings representing the number, position, and magnitude of the spots.[14] Another candidate for the honour of discovering the spots of the sun, was John Fabricius, who undoubtedly saw them previous to June, 1611. The dedication of the work[15] in which he has recorded his observation, bears the date of the 13th of June, 1611; and it is obvious, from the work itself, that he had seen the spots during the year 1610: but as there is no proof that he saw them before the 8th of December, 1610, and as it is probable that Harriot had seen them before that date, we are compelled to assign the priority of the discovery to our distinguished countryman. The claim of Scheiner, professor of mathematics at Ingolstadt, is more intimately connected with the history of Galileo. This learned astronomer having, early in 1611, turned his telescope to the sun, necessarily discovered the spots which at that time covered his disc. Light flying clouds happened, at the time, to weaken the intensity of his light, so that he was able to show the spots to his pupils. These observations were not published till January, 1612; and they appeared in the form of three letters, addressed to Mark Velser, one of the magistrates of Augsburg, under the signature of _Apelles post Tabulam_. Scheiner, who, many years afterwards, published an elaborate work on the subject, adopted the same idea which had at first occurred to Galileo,--that the spots were the dark sides of planets revolving round and near the sun.[16]