86 CELESTIAL PHJENOMEXA. 



. 



unequal density, temperature, and electro-magnetic tension of 

 these rings, may have occasioned differences of form in the 

 sphcroidally condensed matter, as the amount of tangential 

 velocity and small variations in its directions may have caused 

 the diversity of form and inulmotion in the elliptic orbits. 

 Attractions of ma?s, and the laws of gravitation, have, no 

 doubt, been influential here, as well ns during the changes 

 which have produced the irregularities in the terrestrial 

 surface ; but we cannot infer, from present forms, the whole 

 series of conditions which may have been passed through. 

 Even the so-called law of the distances of the planets from 

 the sun, (which led Kepler to conjecture the existence of 

 some planet filling up the void between Mars and Jupiter), 

 has been found numerically inexact for the distances between 

 Mercury, Venus, and the Earth, and requires an arbitrary 

 supposition in the first member of the series. 



The eleven hitherto discovered primary planets -re- 

 volving round our Sun are attended certainly by fourteen, 

 and probably by eighteen secondary planets moons, or 

 satellites ; the primary planets being themselves the central 

 bodies of subordinate systems. We seem to recognise here 

 in the fabric of the universe, an arrangement somewhat 

 similar to that so often shown to us in the development of 

 organic life, where, in the manifold combinations of groups 

 of plants or of animals, the typical form is repeated in subor- 

 dinate circles. The secondary planets, or satellites, are more 

 frequent in the outer region of our planetary system, 

 situated beyond the intersecting orbits of the telescopic 

 planets; none of the planets of the inner division have 

 satellites, except the Earth, whose moon is of great relative 

 magnitude its diameter being to that of the earth as one to 



