122 LIGHT SCIENCE FOR LEISURE HOURS. 



Fortunately, we may view this matter (just as 

 astronomers have learned to view the prospect of mis- 

 chievous collisions with comets) as a question of proba- 

 bilities. Among so many thousands of stars there have 

 been so many sudden outbursts of light and fire, so 

 many sudden defalcations of splendour. Our sun is 

 one of those thousands, and so far as we know takes 

 his chance with the rest. 



From the Spectator for August 1872. 



L-u " ' ' 



........ ,,r-..^ 



NEWS FROM HERSCHEVS PLANET. 



SATURN the altissimus planeta of the ancients re- 

 mains still the most distant planet respecting whose 

 physical condition astronomers can obtain satisfactory 

 information. The most powerful telescopes yet con- 

 structed have been turned in vain towards those two 

 mighty orbs which circle outside the path of distant 

 Saturn : from bevond the vast depths which .separate us 

 from Uranus and Neptune, telescopists can obtain little 

 intelligence respecting the physical habitudes of either 

 planet. Nor need we be surprised at the failure of 

 astronomers, when we consider the difficulties under 

 which the inquiry has been conducted. In comparing 

 the telescopic aspect of Uranus with that of Saturn (for 

 example) we must remember that Uranus is not only 

 twice as far from the earth but also twice as far from 



