COSMIC PHILOSOPHY 



polesf of our solar system, their orbits cutting 

 its equatorial plane at great angles, so the neb- 

 ulae are found in greatest numbers about the 

 poles of the galaxy. It seems unlikely that this 

 parallelism, which Mr. Spencer was the first to 

 point out, should be accidental. It indicates a 

 common mode of evolution of the whole starry 

 system. It vaguely points to a gigantic pro- 

 cess of concentration going on throughout the 

 galaxy, analogous to the local process of con- 

 centration which has gone on in our own little 

 planetary group. Still more obvious will this 

 become when we consider the explanation of 

 these phenomena which Mr. Spencer has offered. 

 Observation shows that while the more con- 

 solidated nebulas are oval or spheroidal in shape, 

 the less consolidated nebulae are often extremely 

 irregular, throwing out long arms of vaporous 

 matter into the adjacent spaces. This agrees 

 with what we have learned to expect in any ro- 

 tating mass which gravitation is slowly draw- 

 ing closer and closer together. The oval form is 

 due, as we have seen, to the combined effects 

 of gravitation and rotatory movement. But this 

 implies an earlier state in which the figure was 

 irregular. Now while the heavier portions of 

 the mass were being drawn together so as to 

 acquire a spheroidal contour, the lighter por- 

 tions, floating farther from the centre of gravity, 

 would remain like detached shreds of cloud, or 

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