12 THE BODIES OF SPACE, 



which the opposing currents met each other: this motion 

 would increase as the agglomeration proceeded : at certain 

 intervals, the centrifugal force acting in the exterior of the 

 rotating mass would overcome the agglomerating force, and 

 a series of rings would thus be left apart, each possessing the 

 motion proper to itself at the crisis of separation. These, 

 again, could only continue in their annular form if uniform in 

 constitution. There being many chances against this, they 

 would probably break up, and be agglomerated into either 

 one or several masses, which would then become representa- 

 tives of the primary mass, and perhaps give rise to a similar 

 progeny of inferior masses. All this Laplace showed to be 

 possible under the physical laws of the universe, and he con- 

 ceived that such might be the actual history of all such 

 systems as ours, the four small planets between Mars and 

 Jupiter being an example of a ring which agglomerated into 

 distinct parts, and the rings of Saturn instances of satellites 

 which have not yet attained, if they ever will attain, the 

 ultimate form assigned to such bodies in general. 



This hypothesis, it will be observed, only comes to the 

 point at which we must needs arrive under a consideration of 

 the " web of relation" traceable in the constituents of the solar 

 system namely, that they have had a common origin in a soft 

 and diffused form of matter. Such a form of matter may now, 

 as is alleged, be no longer actually seen in the heavens ; and 

 yet there may remain good reasons for believing that it once 

 existed. One of these will afterwards be presented in the 

 facts connected with the density of the planets and the internal 

 heat of the earth. As another, I may point to the curious 

 phenomenon called the zodiacal light, an oblate luminosity 

 surrounding the sun, and very conspicuous in the twilights of 

 tropical climes ; a remnant, as has been supposed, of the dif- 

 fused solar atmosphere of the nebular cosmogony. There is 

 even a support to the hypothesis in what would seem at first 

 to be an anomaly and an objection the existence of the 

 many binary and ternary solar systems. It may be supposed 

 that, at a certain point in the confluence of the matter of these 

 regions of space, the solar nuclei would become involved in 



