320 EPOCHS IN THE HISTOEY OF THE CONTEMPLATION OP 



and May of that year. Harriot, to whom Baron Zach attri- 

 butes the discovery of the solar spots (16th Jan. 1610 !) 

 did indeed see three of them on the 8th of December, 1610, 

 and marked their position in a register of observations ; but 

 he was not aware that they were solar spots, as Plamstead, 

 on the 23d of December, 1690, and Tobias Mayer, on the 

 25th of September, 1756, did not recognise Uranus as a 

 planet when seen in their telescopes. Harriot first recog- 

 nised them as solar spots Dec. 1, 1611, five months after 

 Eabricius had published his discovery. Galileo remarked 

 thus early, that the solar spots, " of which many are larger 

 than the Mediterranean, and even than Africa and Asia/' 

 occupy a distinct zone in the sun's disk. He noticed that 

 the same spots sometimes returned, and was persuaded that 

 they belonged to the sun itself. The differences in their 

 dimensions at the centre of the disk, and when near disap- 

 pearing at the margin, particularly arrested his attention; 

 but I do not find, in the remarkable second letter to Marcus 

 "Welser (Aug. 14, 1612), anything that could be interpreted 

 to indicate that he had observed the inequality of the ashy 

 coloured border at the two sides of the black nucleus, when 

 approaching the limb of the sun (Alexander Wilson's fine 

 remark in 1773 !) The Canon Tarde, in 1620, and Mala- 

 pertus, in 1633, ascribed all obscurations of the sun to 

 small revolving cosmical bodies which intercepted his light, 

 and to which the names of Borbonia and Austriaca Sidera 

 were given. ( 49 ) Fabricius recognised, like Galileo, that the 

 spots belong to the sun itself; ( 491 ) he also saw that spots 

 which he had observed disappeared and returned again ; and 

 these phenomena taught him the rotation of the sun, wliich 

 Kepler had conjectured before the discovery of the spots. 



