THEORY of the EARTH. 285 



is raifed by a power which has for principle fubterraneous heat ; 

 but how that land is preferved in its elevated ftation, is a fub- 

 ject in which we have not even the means to form conjecture ; 

 at leaft, we ought to be cautious how we indulge conjecture in 

 a fubject where no means occur for trying that which is but 

 fuppofition. 



WE now proceed, from the facts which have been properly 

 eftablifhed, to reafon with regard to the duration of this globe, 

 or the general view of its operations, as a living world, main- 

 taining plants and animals. 



PART IV. 



Syjlem of Decay and Renovation obferved in the Earth. 



* 



PHILOSOPHERS obferving an apparent diforder and confu- 

 fion in the folid parts of this globe, have been led to con- 

 clude, that there formerly exifted a more regular and uniform 

 ftate, in the conftitution of this earth ; that there had happen- 

 ed fome deftructive change ; and that the original ftructure of 

 the earth had been broken and difturbed by fome violent ope- 

 ration, whether natural, or from a fupernatural caufe. Now, 

 all thefe appearances, from which conclufions of this kind have 

 been formed, find the moft perfect explanation in the theory 

 which we have been endeavouring to eftablilh ; for they are the 

 facts from whence we have reafoned, in difcovering the nature 

 and conftitution of this earth : Therefore, there is no occafion 

 for having recourfe to any unnatural fuppofition of evil, to any 

 deftructive accident in nature, or to the agency of any preter- 

 natural cavife, in explaining that which actually appears. 



IT 



