198 A CENTURY'S PROGRESS IN ASTRONOMY. 



trained at Slough by Mr Rogers, a Scot- 

 tish mathematician. At the age of seventeen 

 Herschel entered the University of Cambridge, 

 and Caroline Herschel, who was exceedingly 

 proud of him, recorded in her memoirs that he 

 gained all the first prizes without exception. 

 He left the University in 1813. 



John Herschel did not turn his attention to 

 astronomy until he had attained the age of 

 twenty-four. In a letter to a friend, September 

 10, 1816, he said, "I am going, under my 

 father's directions, to take up star-gazing." It 

 was only reverence for his father that made him 

 turn to astronomy, and he gave up the science 

 he loved most chemistry. But his unselfishness 

 received its reward. In 1820 John Herschel 

 constructed his first reflector under his father's 

 guidance. Four years previously he had begun 

 to observe double stars, which had been for long 

 studied by his father, who discovered their 

 revolutions. These observations were continued 

 from 1821 to 1823 at the Observatory of Sir 

 James South (1786-1867). John Herschel and 

 South measured 380 of the elder Herschel's 

 double stars. These investigations gained for 

 Herschel and South the Lalande Prize of the 

 French Academy and the Gold Medal of the 

 Royal Astronomical Society. 



