230 ETHER AND GRAVITATIONAL MATTER. 



Sec. 22. There may also be a large amount of matter in many stars 

 outside the sphere ol" 3.10" kilometers radius, but however nuich mat- 

 ter there may be outside it, it seems to be made highly probable by 

 sections 11-21 that the total quantity of matter within it is greater 

 than 100,000,000 times and less than 2,000,000,000 times the sun's 

 mass. 



I wish, in conclusion, to express my thanks to Sir Norman Lock3^er, 

 to the Astronomer Royal, Mr. Christie, to Sir Robert Ball, and to Pro- 

 fessor Becker for their kindness in taking much trouble to give me 

 information in respect to astronomical data, which has proved most 

 useful to me in sections 11-21, above. 



