218 ]PACTS AND THEORIES. 



planet was ever before as near the sun as it now is ; that, 

 at first, all the planets and the sun constituted one mass 

 of highly attenuated matter extending beyond the orbit 

 of Neptune ; that this matter was drawn centreward, 

 condensing more and more, and somehow getting itself 

 into a rotation around its centre of gravity, with ever in- 

 creasing speed, until the centrifugal force became 

 sufficiently great to stop the inward movement of the 

 external portion ; that the central part continued to con- 

 dense, but the ring left behind, broken to pieces by the 

 mutual attraction of its parts, was gradually gathered 

 up into a sphere, the first of planets, now known as 

 Neptune ; that Uranus, Saturn, Jupiter, Mars and their 

 sister planets were formed in the same way. And now, 

 along comes another scientist and says : This won't do, 

 this theory needs emendation. There are those frag- 

 mentary bodies in Inter-planetary space, once probably 

 far more nunerous than now. They must have played 

 an important part in world- making. The planets at 

 their first condensation from nebulous matter were very 

 small, perhaps smaller than the least of the asteroids, 

 but for all that immensely larger than these little bodies, 

 and hence by their superior attraction, drew to them- 

 selves infinite numbers of them, and so, through count- 

 less ages, the planets grew to their present size. 



Fifty years ago it was taught that the sun was a 

 magnificent world inhabited by beings more favored 

 than the denizens of earth. Shielded by a canopy of 

 phosphorescent clouds, they dwelt in perpetual spring 

 and endless day. Poet-philosophers exhausted their 

 imaginations depicting the beauties of the solar land- 

 scape. To them it was the region of the blessed, for do 

 we not read : "There shall be no night there?" and 

 where else could that promise be realized ? But now 

 philosophers tell a very different story. The sun, they 

 say, is a collection of inconceivably hot vapors and 



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