ASTRONOMY. IGI 



This table shows the influence of the Milky Way most maikodly ; but 

 if changed so that the number of stars iu zone 5 is always l.UO, it be- 

 comes even more interesting. 



Class 1. Classes 2-7. 



Zone 1 0.55 0.35 



2 0.57 0.36 



3 0.64 0.45 



4 0.79 0.68 



5 1.00 1.00 



6 0.91 0.77 



7 0.57 0.47 



8 0.43 0.41 



If we call these last numbers D, and if we form 1=5, these numbers 

 may be called the gradients (G), expressing the rapidity of increase of 

 number of stars as we approach the Milky Way. The values of Gr are — 



Class 1 0.36 Class 5 0.44 



2 0.48 6 0.45 



3 0.42 7 0.45 



4 0.47 8 0.52 



Classes 2-7, 0.50. 



It thus appears probable that G is greater for the fainter stars, but 

 not so much greater as hafc been commonly supposed. For stars of 

 the mags. 1, 2, 3, and of the mags. 4, 5, 6, G results 0.14 and 0.19. These 

 numbers show an important difl'erence between the bright and the faint 

 stars. If we were allowed to assume that stars even fainter than 9.5 

 would continue to show the constant gradient that these show it would 

 follow that our stellar system was not to be considered as a flat disk, 

 but rather more or less spherical, with the stars concentrated near its 

 medial plane (the Milky Way). 



The author next proceeds to compute the center of gravity of each 

 class of stars, and its position is — 



Class 2 E. A. 



3 



4 



5 



6 



7 



0) 



The last column gives the ratio y for each class ; where E is the dis- 

 tance of the center of gravity of all stars of the class, r that of any star 

 of that class. 



The full interpretation of these numbers can only be made when 

 S. Mis. 33 11 



