464 Sir George H. Darwin on Sir William, Herschel. [April 26, 



gained a great extension at the hands of Kapteyn and of many others, 

 and it has been proved that other systematic; motions of the stars are 

 discoverable. The time at my disposal will not permit me to pursue 

 this subject further, but I may say that it now appears that if we 

 could view the universe from the centre of gravity of the stars of the 

 Milky Way, we should see a current of stars coming from a definite 

 direction of space and penetrating our system. 



What a vista of discoveries do these ideas open up to the astro- 

 nomer ! Some centuries hence the sun's apex may have shifted, and 

 we may perhaps learn that the solar system is describing the arc of some 

 colossal orbit. The drift or current of stars may also have begun to 

 change its direction, and our descendants may have begun to make 

 guesses as to its future course and as to its meaning. But whatever 

 developments the future may have in store, we should never forget 

 that the foundation of these grand conceptions of the universe was 

 laid by Herschel. Holden ends his " Life of Herschel" with words 

 which may also serve as a fitting end to my lecture : " As a practical 

 astronomer he remains without an equal. In profound philosophy he 

 has few superiors. By a kindly chance he can be claimed as the 

 citizen of no one country. In very truth his is one of the few names 

 which belong to all the world," 



[G.H.D.] 



