THEIE ARRANGEMENTS AND FORMATION. 7 



solar system, most of which have also been discovered since the 

 days of Newton. It is, in the first place, remarkable that 

 all the planets move nearly in one plane, corresponding with 

 the centre of the sun's body. Next, it is not less worthy of 

 attention, that the motion of the sun on its axis, those of the 

 planets around the sun, and the satellites around their pri- 

 maries, 1 and the motions of all on their axes, are in one direc- 

 tion namely, from west to east. Had all these matters been 

 left to accident, the chances against the uniformity would have 

 been, though calculable, inconceivably great. Of the motions 

 of the twenty-three bodies known in the early part of this cen- 

 tury, it was found by Laplace, that the adverse chances were 

 as upwards of four millions of millions to one. It is thus 

 powerfully impressed on us that the uniformity of the motions, 

 as well as their general adjustment to one plane, must have 

 been a consequence of a single cause acting throughout the 

 whole system. 



Some of the other relations of the bodies are not less re- 

 markable. It is, perhaps, of little consequence that the Larger 

 planets are towards the outside of the system, since there is an 

 absence of regularity in the gradation in this respect. In the 

 series of comparative densities we find an approach to a regular 

 gradation : they stand thus in decimals, the Earth being con- 

 sidered as 1 Mercury, 2 -95 ; Venus, -99 ; Earth, 1 ; Mars, '79; 

 Jupiter, '23 j Saturn, '11 ; Uranus, '26 ; the last being the 

 only very decided violation of the rule. Then the distances 

 are curiously relative. It has been found that, if we place 

 the following line of numbers, 



3 6 12 24 48 96 192, 



and add 4 to each, we shall have a series denoting the 

 respective distances of the planets from the sun. It will stand 

 thus 



1 There is an exception, but doubtless apparent only, in the motion 

 of the satellites of Uranus, which, compared with the rest, is retrograde. 

 The axes of the planets are, as is well known, at various degrees of in- 

 clination to their orbits ; for which there must have been a cause in the 

 circumstances under which the planets were produced. The axis of 

 Uranus is removed but eleven degrees from the plane of his orbit : I 

 suggest, as the explanation of the apparent exception, that what we call 

 the north pole of this planet is in reality the south, the axis having 

 passed across the plane of the orbit, so that the planet may be said to 

 be in that small measure upside down. It will be observed, that be- 

 tween the admitted and the suggested arrangement, there is only a dif- 

 ference of 22 degrees. 



