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IIUTTONL\N THEORY. 



hee 



endeavouring 



the natural hill 



ry of the earth. A farther proof of the fame 

 fes from confidering, that for every give 

 of matter, h 

 there are two 



maf 



s 



itter, having a given period of rotation, 

 are two different fpheroids that anfwer the 

 conditions of eftablifhing an equilibrium among 

 its parts, the one near to the fphere, and the 

 other very diftant from it, and fo oblate as to 

 have a lenticular form. Thus the earth, fuppo- 



ling it homogen 



ght either be 



quili 



brio, by means of the figure which it adually has, 

 or of one in which the polar was to the equatorial 



; is true of the 

 ^here fmd that 



diameter as I to 768. The fam 



other pi 



d yet 



no 



this highly comprefled fpheroid is adually em 



ployed by 



The reafon, no doubt, is, that 



in fo oblate a fpheroid, the equilibrium between 

 the gravitating and the centrifugal force is of the 



kind that d 



c 



L 



re-eftablifh itfelf when dif- 

 urbed ; fo that the parts let loofe, and not kept 

 in their place by firm cohefion, would fly offal- 

 together. In fuch a body, the wafte at the' fur- 

 face would lead to an entire change of form, and 

 therefore the conflitution here fuppofed could 

 not be permanent. 



443. In the fyftem of Saturn, we have a great 

 deviation from the general order, which, nevcr- 

 thelefs, has led to a very unexpeded verification 

 of fome of the conclulions deduced above. 



A 



principle 



