AH that we can do, is to judge by the effedls 

 we fee. Thefe indeed are very great. Every 

 kind of fubftance is calcined by the fubterra- 

 neous fire. 



It is fuppofed, that all metals are formed 

 by the vapoiris arifing therefrom, which tinge 

 the mineral waters. Thefe, wherever they 

 run, convert the earth into the different me- 

 tals, often mixed together in the ftate they 

 are found in the bowels of the earth. 



What makes it probable, that all minerals 

 are formed by the vapours arifing from the 

 internal fire, is, that as often as you melt any 

 metal, its weight is diminifhed ; and, if the 

 fire is continued for any length of time, the 

 greateft part will evaporate. You may col- 

 led: fbme metallic calces at the top of the fur- 

 nace, although very high, where much me- 

 tal is melted. 



Since writing the foregoing treatife, I have 

 read Dr Hutton's Theory of the Earth. Se- 

 veral of the Doctor's arguments prove what 

 is here alledged, and likewife what is faid in 

 National Improvements, pages ift, 2d, 4th, 

 5th, 6th, i yth, and 1 8th. His reafoning is, 

 in general, ingenious ; but I cannot admit; 

 the following conclufion which he draws ; 



"But 



