j8 HISTORT of the SOClErr. 



mentioned do not enable me to ftate. We may neverthelefs 

 conje(5lure, with confiderable probability, what the ftep was 

 which immediately followed. 



It muft have occurred to him, as an objedlion to the confoli- 

 dation of minerals by fubterraneous heat, that many fubftances' 

 are found in the bowels of the earth in a ftate altogether unlike 

 that into which they are brought by the ai5\ion of our fires at 

 the furface. Coal, for inftance, by expofure to fire, has its parts- 

 diflipated ; the afhes which remain behind are a fubftance quite- 

 different from the coal itfelf ; and hence it would feem that this 

 foffil can never before have been fubje6ted to the adlion of fire. 

 But is it certain, (we may fuppofe Dr Hutton to have faid to^ 

 himfelf ), if the heat had been applied to the coal in the interior 

 of the earth, at the bottom of the fea, for example, that the fame 

 diffipation of the parts would have taken place? Would not the 

 greater compreffion that muft prevail in that region have pre- 

 vented the diffipation, at leail till a more intenfe heat was ap- 

 plied ? And if the diffipation was prevented, might not the mafs, 

 after cooling, be very different from any thing that can be ob- 

 tained by burning at the furface of the earth ? It is plain that 

 there is no reafon whatever for anfwering thefe queftions in the ne- 

 gative. And, on the contrary, if the analogy of nature is confult- 

 ed, if the fa^ of water requiring more heat to make it boil when 

 it is more eompreffed, or the experiments with Pa pin's digefter, 

 be confidered, it will appear that the anfwer muft be in the 

 affirmative. Nay, it could not but feena reafonable to proceed 

 a ftep farther, aixi, as the mixture of fubftances is known in fo 

 many inftances to promote their fufibility, to fuppofe that when 

 the volatile parts of bodies were reftrained, the whole mafs- 

 might be reduced into fufion by heat, though, when thefe fame- 

 parts were driven off, the refiduum might be altogether infu- 

 fible. Thus coal, when the charcoal and bitumen are for- 

 ced to remain in union, may very well be a fufible fubftance,.. 



though,. 



