The heavens above: a popular handbook of astronomy (1882)
Gillet, J. A. (Joseph Anthony), 1837-1908 · New York, Chicago, Potter, Ainsworth, & Co. · leaf 208
Fig. 202. 186. The Proper Motion of the Spots. — When theperiod of the suns rotation is deduced from the motion ofspots in different solar latitudes, there is found to be con-siderable variation in the results obtained. Thus spots near 188 ASTRONOMY. the equator indicate that the sun rotates in…
Astronomy
Internet Archive · Cornell University Library · Public Domain Mark 1.0. Free to use for anything.