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cause the evaporation of a planet cannot extend so far 

 from it, such a ring is impossible. If any one should 

 desire to know why the earth has got no ring, he will 

 find the answer in the greatness of the semi-diameter 

 which it was necessary for its interior border to have, as 

 this must have been 289 semi-diameters of the earth. In 

 the case of the planets that move more slowly, the pro- 

 duction of a ring is still further from possibility. And 

 thus there is no case in which a planet could have 

 acquired a ring in the way we have explained but that 

 of the planet which actually has one ; and this is no 

 small confirmation of the credibility of our explanation. 



But what makes me almost sure that the ring which 

 surrounds Saturn was not acquired in the general way, nor 

 has been produced by the universal laws of formation which 

 have ruled the whole system of the planets, and which 

 have procured for Saturn his satellites also, is this : that 

 the external matter did not furnish the material for it, 

 but that it is a creation of the planet itself which has 

 sent off its most volatile parts through its heat and has 

 communicated to them by its own axial rotation the 

 impulsion to revolve around it. My conviction is founded 

 on the fact, that the ring is not situated in the general 

 plane of the planetary movements, like its own other 

 satellites, and generally all the revolving bodies which are 

 found accompanying the planets, but its direction deviates 

 considerably from that plane. This is a sure proof that 

 the ring has not been formed from the universal primitive 

 matter, and that it has not acquired its motion from the 

 falling of such matter; but that it has ascended from the 

 planet long after its formation was complete, and that it 

 obtained a motion and direction related to the axial 



