134: OEIGIN OF THE EARTH. 



accordance with, and explains, the fact, universal in the solar 

 system, and doubtless in other departments of the cosmical 

 creation, that when bodies (whether planets or satellites) re- 

 volve in elliptical orbits,, their primaries, or centers of gravity, 

 are invariably situated in one of the foci of the ellipse, pre- 

 cisely where, according to our theory, such bodies must, in all 

 probability, have been originally formed. It may be added 

 that, of the fact of this focality in the situation of primaries 

 with reference to the elliptic orbits of their secondaries, no 

 other hypothesis than the general one now under consideration 

 affords the slightest explanation. 



Considering the earth and the moon as having, in this way, 

 been formed respectively by condensations in the foci of the 

 same original nebulous mass, their origin and relations may 

 be considered as hinting at, if not exactly representing, the 

 origin and relations of the two bodies of what are called 

 double stars, or binary systems. The diversity of colors gene- 

 rally observed as characterizing the two constituents of such 

 systems the larger body being, in most cases, relatively red, 

 and the smaller relatively blue, as though they had divided 

 the prismatic colors between them strongly intimates, of it- 

 self, something like a polar opposition in the materials of which 

 they are respectively -composed, and gives additional weight 

 to the hypothesis of their original and nebulous connection. 



The hypothesis of an original union in one nebulous body 

 of the materials of the earth and moon, seems, indeed, to bo 

 necessary, if there is admitted to be any truth in the nebular 

 theory. But, if this hypothesis is true, it suggests a connec- 

 tion of a nature heretofore little suspected, as even now sub- 

 sisting between the earth and moon. Taken in connection 

 with our doctrine of constant emanation, as well as constant 

 gravitation, of particles governed by the laws of assimilation, 



