COSMIC PHILOSOPHY 



that they are nebulous in constitution, it appears 

 highly probable that they are simply outlying 

 shreds of the nebula from which our planetary 

 system has been developed. As for the irre- 

 solvable patches of nebulous matter which are 

 distributed about the poles of the galactic circle, 

 their distance from us is so great that we have 

 not yet ascertained anything trustworthy con- 

 cerning their motions. But the fact that their 

 position in high galactic latitudes is explicable 

 upon the same general principles which explain 

 the positions of comets, raises a presumption 

 that their relation to the galaxy as a whole may 

 somewhat resemble that which comets bear to 

 the solar system. Between the possible careers 

 of the nebulae and the comets, there is, how- 

 ever, a mighty difference. The nebula which 

 we see through quadrillions of miles shining by 

 a light of its own must needs be an enormous 

 object — enormous in mass as well as in vol- 

 ume — and its gravitative force must be pro- 

 portionate to its size. While, therefore, its grad- 

 ual contraction is likely to be attended by its 

 development into a planetary system, — by a 

 process of integration and differentiation such 

 as we have here described, — on the other hand 

 the comet is an object of inconsiderable mass, 

 though very often of considerable volume. The 

 slight concentration of which it is capable will 

 not produce planetary systems or even asteroids, 

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