A RATIONAL COSMOGONY 147 



and may not improbably have countless satellites be- 

 yond the power of our telescopes to descry. Besides, it 

 need not be affirmed that all the planets have the same 

 individual histories; for both Uranus and Neptune may 

 have undergone capture by gravitational "interfer- 

 ence/- as previously explained. If this is truly the spe- 

 cific method by which our system was formed, the ap- 

 pearance of the resulting nebula to a distant observer 

 must have been of the spiral sort, exhibiting glowing 

 nuclei of condensation. 



Always an interesting subject for speculation is 

 that of the probable age of the earth. Heretofore the 

 astronomers have found it impossible to reconcile their 

 cosmogonical theories with the undeniable evidences of 

 geology. (ieology demands an earth of at least 

 200,000,000 years, a uniform solar heat, and a uniform 

 terrestrial heat, none of which does orthodox astronomy 

 find itself able to supply. In lieu thereof she offers an 

 earth aged about ten million, and as to the other two 

 requirements advises Geology to be less finical. 



Now according to these views there are three sep- 

 arate logical ways whereby the earth may have become 

 a member of the solar system. One of these I have 

 but just described. The second is by interference 

 caused by the impingement of spheres of gravitational 

 influence; and the third, by explosive ejection from 

 some deceased neighboring sun. The first of these 

 allows for an indefinite past, long or short, as geology 

 may itself determine; but the two latter demand an 

 all but interminable period. If the earth gained mem- 

 bership by the second method, its age may be judged by 

 the fact of five other planets having come in later. 

 If by the third, untold eons must have been required 

 to train it down to orbital circularity. Hence I con- 

 clude that the onlv reliable criterion we have as to 



