SIB WM. AND CAROLINE UERSCHEL. 93 



So busy that he could not find time to eat or 

 ! Rare devotion of a rare mind ! He now 

 began to study every star of the first, second, third, 

 and fourth magnitudes in the sky. He carefully 

 observed the moon, and measured the height of 

 about one hundred of her mountains. Her extinct 

 volcanoes, and her unpeopled solitudes, without 

 clouds or air, were an impressive study. 



He was now forty years old, not young to 

 begin the study of a new and illimitable science, 

 but not too old, for one is never too old to begin a 

 great or a noble work. 



Through Dr. William Watson, Fellow of the 

 Eoyal Society, who happened if anything ever 

 happens in this world to see Herschel at his 

 telescope, he became a member of the Philosophi- 

 cal Society of Bath, and soon in 1780 sent two 

 papers to the Royal Society, the one on the peri- 

 odical star in Collo Ceti, and the other on the 

 mountains of the moon, which were read by Dr. 

 William Watson, Jr. 



When he was forty -three, he says, " I began to 

 construct a thirty -foot aerial reflector, and, having 

 made a stand for it, I cast the mirror thirty-six 

 inches in diameter. This was cracked in cooling. 

 I cast it a second time, and the furnace I had 

 built in my house broke." But he persevered. 

 This same year, 1781, after he had lived in Bath 

 nine years, on the night of Tuesday, March 13, 

 having removed to a larger house, 19 New King 

 Street, he says, "In examining the small stars in 



