22 



STATEMENT AND EXPOSITION OP 



Specialities of the Half-Planets Earth and Venus. 



1. In accordance with the immediately preceding conchision, the exterior half- 

 planet, the Earth, not merely shows a density greater than that of its interior 

 half-planet Venus, but also, as seen in Table (A), in (3), a density altogether re- 

 markable in view of the Earth's place in the planetary system. 



2. The inclination of the equator of Venus to the plane of that planet's orbit 

 (from 73° to 75°, most probably) presents a marked contrast to what we find in 

 the cases of Mercury, the Earth, and Mars, in all which the inclination of the 

 equator approaches to a mean value that is nearly the same with the obliquity of our 

 equator to the ecliptic ; and this, while a like contrast does not exist in the respect 

 of the time of rotation (the sidereal day) of Venus ; for that is nearly the same with 

 each of the respective sidereal days of these same other three planets, in this region 

 of the system. But the inclination of the equator of Venus is, up to the present 

 time, without a parallel i.n all the system, except in the instance of another half- 

 planet, viz. Uranus.' 



And here the state of things is, withal, as though the enormous deviation of the 

 plane of the equator from the plane of the planet's own orbit (and which implies 

 also a very large deviation from the plane of the sun's equator) were itself due to 

 the attraction towards the more dense outer portion, already commented on, which 

 went to the formation of the Earth ; an attraction acting in a direction nearly per- 

 pendicular to the half-planet's first-forming equator and its parallels. 



Thus the material, at its first rolling up from the form of a ring or shell, 

 would be inclined to rotate in the plane of EW, but being drawn outward by the 

 attraction of the more dense material in the direction EN, the resultant rotation 

 would be in a direction such as EO, as represented in the figure at 1, and trans- 

 ferred to the position marked 2. 



All this might begin antecedently to the process of rending which introduced 

 the formation of half-planets, or perhaps go on during that very process ; in which 



' During the revolution of a whole ring or shell around the sun, every part of the outside would 

 be presented once in its turn to the entire circuit of the heavens ; and so in effect vrould rotate once 

 around a point within that ring or shell. This would determine the angular velocity of rotation at 

 the first gathering up to form a planet. The existence of more dense material outside would seem 

 not to have superinduced a retrograde rotation in this case ; but to have Interfered to the preventing 

 of an accelerated rotation, and thus the more dense material be kept outside, until, in the contest of 

 forces, the rending into two half-planet masses took place. The existing state of things, in its vari- 

 ous aspects, seems to look toward this; but the problem is too complicated a^one to justify an asser- 

 tion that such was the succession of events. 



