HUTTONIAN THEORY 



9'' 









It 



■;£ 



lit 



If 



tl 



tt 



difficult to account for a fire of fuch adivity, 

 and of fuch long continuance in the fame 

 fpot, by any decompofition of mineral fubftances 

 near the furface. In the place where this com- 

 buftion is fuppofed to exift, it mull be remem- 

 bered, that there is no frefn fupply of materials 

 to replace thofe that have been confumed, and 

 that, therefore, the original accumulation of 

 thefe materials in one fpot, mufl: have been very 

 unlike any thing that has ever been obferved 



difpolition of minerals in the 



concernmg 



th 



e 



bowels of the earth. 



89. If, on the other hand, we afcribe the 

 phenomena of volcanoes to the central heat, the 

 account that may be given of them is limple, 

 and coniiitent with itfelf. According to all the 

 appearances from which the exiftence of fuch 

 heat has been inferred above, it is of a nature fo 

 far different from ordinary fire, that it may re- 

 quire no circulation of air, and no fupply of 



combuftible materials to fupport it. It is not 

 accompanied with inflammation or combuftion, 

 the great prelTure preventing any reparation of 

 parts in the fubftances on which it afts, and the 

 ab fence of that elaftic fluid without v/hich heat 

 feenis to have no power to decompofe bodies, 

 even the moft combuftible, contributing to the 

 unalterable nature of all the fubftances in the 



^ 



mineral regions. There, of confequence, the 



r 



only 



