PROOF OF EXISTENCE OF A SUPRA- WORLD 1 07 



without our becoming aware of it. But the extreme 

 improbability of such an arrangement may encourage 

 us to take trie irregularity of distribution for granted. 

 The fourth assumption is one that does not commend 

 itself to any one who looks for a definite epoch at 

 which the visible universe was created. But to any 

 one familiar with the line of reasoning derived from 

 atomic conditions, the eternity of stars must appear 

 extremely probable, whatever may be said of their 

 luminosity or their individual fate. 



The second assumption is, I think, the most im- 

 portant, as it bears upon the validity of the law of 

 gravitation. 



Suppose that the number of dark stars in the 

 Milky Way exceeded the bright ones by 1000 : 1, 

 and that there was a greater preponderance else- 

 where, sufficient to bring the density of our stellar 

 system up to about 10~ n , water being unity. In 

 other words, out of every 100,000 million cubic 

 miles of stellar space, one cubic mile would be occu- 

 pied by the material of a star, a planet, or a dark 

 sun of the average density of water. The assump- 

 tion contains nothing very improbable: the number 

 of dark bodies is suspected to be very large in any 

 and even a great preponderance would not 

 materially increase the occultations and variabilities 

 usually observed. 



Now it is obvious that if all space were uniformly 

 strewn with bright stars, many of these would at any 



