ORIGIN OF THE WORLD 



Now in point of fact, something very like this is 

 the interpretation which the astronomer puts upon 

 the spiral nebula. He believes that its central lumi- 

 nous nucleus is an incandescent gaseous body like our 

 sun, and that the two spirals that lead out from it, 

 with their irregularly scattered foci of light, and their 

 filmy veils of luminous smoke, represent matter that 

 has burst forth from the central body, and that is 

 now revolving about the central axis very much as 

 the pin-wheel revolves about its central pin. Only 

 of course the axis in this case is an imaginary body, 

 like the axis of our sun or the earth's pole, and the 

 span of the entire nebula is to be measured in un- 

 thinkable millions of miles. 



There is a nebula in the constellation Andromeda 

 that is estimated to be so wide that light requires at 

 least eight years to span it. Its distance across is 

 at least five hundred thousand times the earth's dis- 

 tance from the sun. It is faintly visible to the na- 

 ked eye. 



Regardless of size, however, what gives the spiral 

 nebula interest from the present standpoint is the fact 

 that nebulae have long been regarded as the matrix 

 out of which solar systems such as ours are developed. 



For about a hundred years astronomers had held 

 as stock doctrine the theory of Laplace, according to 

 which our solar system originated from a super- 

 heated gaseous globe which contracted as it cooled, 

 and from time to time threw off rings of its equatorial 

 substance that became planets. 



But Professor Keeler's nebulae seemed to contra- 

 dict this theory. The spiral nebula quite obviously 



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