ROTATION OF THE GALAXY — EDDINGTOl?!" 257 



haps not sufficiently recognizing that by the time these conditions 

 prevail there will be no galaxy left. 



Let us leave these deep waters of theoretical investigation, and for 

 our last look at the galaxy use no other criticism than our common- 

 sense. We have not much difficulty in imagining ourselves looking 

 at it from outside, for the lelescope reveals multitudes of spiral 

 nebulae, seen from every aspect, any one of which, we believe, may 

 be taken as a pattern of our own galaxy. Rotating? Obviously it 

 is. It is just like a Catherine wheel. Permanent? It does not look 

 very permanent. Every engineering instinct we possess protests that 

 such disklike arrangements of matter are precarious, and their sta- 

 bility is not to be trusted. To emphasize our sense of the transitori- 

 ness of things, the other galaxies are rushing away at high speed as 

 though our poor system were the plague-spot of the universe. In a 

 few thousand million years our neighborhood will be nearly evacu- 

 ated, and our skies will have lost one of their chief telescopic glories. 

 This is a rough and ready way of treating serious problems, but it 

 is not out of harmony with the results thrust upon us by stricter 

 methods. Perhaps the lesson of the galaxies is to wake us from our 

 dream of leisured evolution through billions of years. It is hard to 

 credit our stellar system with so much age and endurance. It is 

 more like a young man in a hurry. 



