BicKERTON. — On the Origin of the Visible Universe. 177 



degrees wide, extending around the heavens, including the milky way. * 



* * This belt will include one-fourth the surface of the celestial sphere. 



* * * Here we find nine-tenths of the star-clusters, and one-tenth 

 of the nebulae." In another paper I shall attempt to show that most 

 likely these few nebulaB are not of the same order as the polar nebulae. 



Proctor, who discussed these facts very fully, after showing that star- 

 clusters essentially belong to the galaxy, and, as we pass from that 

 great circle, we go through regular stages of lessening solvability to 

 the galactic poles, and there the nebul® are completely irresolvable, 

 says: — "I believe that cause may be assumed not unreasonably to be 

 the difference in the circumstances under which the galactic and extra- 

 galactic nebulae have reached their present state." Again, in respect 

 to the nebulae at the poles of the milky way. Proctor shows that every 

 theory of their existence is ridiculous, "unless we concede that the nebulEe 

 belong for the most part to our galactic system." The accompanying 

 charts and sketches by Sidney "Waters, Proctor, and Newcombe, show 

 strikingly this most remarkable arrangement. Thus, so far, we see that 

 the milky way is a region of stars and star-clusters, and that the poles of 

 this ring are regions of nebulae. I shall now show that om* sun occupies 

 roughly the centre of this system, in a region poor in stars. Proctor says, 

 after a very long discussion of the question, "all these phenomena point to 

 the conclusion that the milky way, m this neighbourhood at any rate, is 

 really what it appears to be — a belt or zone of stars, separated from us by 

 a comparatively starless interval." After discussing various hypotheses, he 

 says : — "In either case we must assume that our sun is not very far from 

 the centre of the system." The picture of the universe we obtain from these 

 extracts is a clear and distinct one. But perhaps the most striking argu- 

 ment that has yet been offered for the common origin of the universe is that 

 of the spectroscope ; which shows identity in the composition of the sun 

 and stars with the elements to be found in the earth. The analyses of 

 meteorites, in which no extra terrestrial element has ever been found, clearly 

 point to the same conclusion. 



I will give the opinions of a few astronomers on the evidence I have 

 offered. Sir William Herschel distinctly states, that any sound theory of 

 the universe must account for the peculiar arrangement of the nebul®. 

 Proctor, in speaking on grounds of probabihty, says: — "Where the results 

 are in direct contact, the rich regions for one order corresponding to the 

 poor regions for the others, and vice versa, the two orders of objects belong 

 to one system," and again says that he knows of no single reason for sup- 

 posing these nebulae to be external galaxies. That nebula are not external 

 galaxies is proved from the facts recorded by Schmidt, Hind, and others, 



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