74 A CENTURY'S PROGRESS IN ASTRONOMY. 



a few years, however, the society came to an 

 end, and the enthusiasts formed themselves into 

 the lunar section of the British Astronomical 

 Association, on the foundation of that society 

 in 1890. Chief among those English seleno- 

 graphers was Thomas Gwyn JElger (1837-1897), 

 whose observations of the Moon and drawings 

 of the various craters were of the utmost value. 

 Two years before his death, in 1895, Elger pub- 

 lished his important work, * The Moon/ along 

 with an exhaustive chart of the visible face of 

 our satellite. 



Herschel and Schroter firmly believed in the 

 existence of a lunar atmosphere, the latter 

 believing that he had actually observed the 

 Moon's atmospheric envelope. Early in the 

 nineteenth century it was soon observed, how- 

 ever, that on the Moon passing over and occult- 

 ing stars, these stars disappeared suddenly 

 behind the Moon's limb, instead of gradually, 

 as they should have done, had an atmosphere 

 of any density existed. Accordingly astrono- 

 mers gave up believing in a lunar atmosphere. 

 On January 4, 1865, Huggins observed with 

 his spectroscope the occultation of a small star 

 in Pisces. There was not the slightest sign of 

 absorption in a lunar atmosphere ; the entire 

 spectrum vanished at once. 



