The Milky Way 



in course of condensation. The same would 

 appear true of the Pleiades. The photographs 

 of this group, obtained by M. Henry at the 

 Paris observatory, show threads of nebulous 

 matter extending from one star to another, 

 suggesting remains of cosmic substance surviving 

 condensation. Photographs of the nebula of 

 Andromeda have, likewise, revealed within it 

 several gaseous rings, surrounding an enormous, 

 ill-defined central mass. 



The sky seems thus to offer us many transi- 

 tions between the purely gaseous nebula and the 

 star properly so-called. One of the most re- 

 markable of these transition forms is the 

 globular cluster. The isolation of these 

 agglomerations of stars on the dark background 

 of the sky, as well as the regularity of their 

 forms, generally circular or elliptical, force us to 

 the conclusion that they constitute independent 

 systems. The cluster of Omega Centauri is 

 visible to the naked eye in the form of a round 

 nebula approximating in brightness to a star 

 of the fourth magnitude; but under high 

 magnification it resolves itself into an agglo- 

 meration of stars from the thirteenth to the 



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