The Evolution of the Sciences 



we look in the direction of the greatest width 

 of this cosmic nebula, that is to say, in the 

 plane of the galactic circle, we see a regular 

 swarm of stars. The stars are not more serried 

 in this direction, but they extend out to greater 

 depths; at the same time the two external 

 rings appear to us as two milky trails. These 

 rings would appear entirely separate if we were 

 placed at the centre of the world, on Alcyone; 

 but, seen from the position occupied by us, 

 they partly hide each other, which explains 

 why one-third of the Milky Way appears to be 

 double. If we now regard the remaining regions 

 of the sky we shall find a firmament much 

 poorer in stars. This is because our line of 

 vision is traversing the flattened part of the 

 central mass that is to say, it is directed along 

 the smallest diameter of our nebula; these are 

 consequently the directions in which the stars 

 are necessarily most scattered. It is what 

 happens when one enters the outskirts of a 

 wood: in front an innumerable multitude of 

 trees, but, looking back, only a few trunks pro- 

 jected against the sky. 



We are thus able to evolve order out of 

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