276 THE KEBULAE HYPOTHESIS. 



will be equal to three times that of the second ; " and 

 *' from this it results that the situations of any two of them 

 being given, that of the third can be found." N'ow here, as 

 before, no conceivable advantage results. Neither in this 

 case can the connexion have been accidental : the probabil 

 ities are infinity to one to the contrary. But again, accord 

 ing to Laplace, the Nebular Hypotjiesis su2:>plies a solution. 

 Are not these significant facts ? 



Most significant fact of all, however, is that presented 

 by the rings of Saturn. As Laplace remarks, they are, as 

 it were, still extant witnesses of the genetic process he 

 propounded. Here we have, continuing permanently, 

 forms of matter Hke those through which each planet and 

 satellite once passed ; and their movements are just what, 

 in conformity with the hypothesis, they should be. " La 

 duree de la rotation d'une planete doit done etre, d'apres 

 cette hypothese, plus petite que la duree de la revolution 

 du corps le plus voisin qui circule autour d'elle," says La- 

 place.* And he then points out that the time of Saturn's 

 rotation is to that of his rings as 427 to 438 — an amount 

 of difference such as was to be expected. 



But besides the existence of these rings, and their 

 movements in the required manner, there is a highly sug- 

 gestive circumstance which Laplace has not remarked — 

 namely, the place of their occurrence. If the Solar Sys 

 tern was produced after the manner popularly supposed, 

 then there is no reason why the rings of Saturn should not 

 have encircled him at a comparatively great distance. Or, 

 mstead of being given to Saturn, who in their absence 

 would still have had eio^ht satellites, such ringrs mis^ht havu 

 been given to Mars, by way of compensation for a moon. 

 Or they might have been given to Uranus, who, for pur- 

 poses of illumination, has far greater need of them. Ou 

 the common hypothesis, we rej^eat, no reason can be as- 

 * " Mecanique Celeste," p. 346. 



