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The process by which this substance is formed I shall take the 

 liberty to consider as of the fermentative kind, and shall distinguish 

 it by the name of BITUMINOUS FERMENTATION; defining it A 

 fermentation peculiar to vegetable matter placed in such situations, as not 

 only exclude the external air, and secure the presence of moisture, but 

 prevent the escape of the more volatile principles ; and which terminates 

 in the formation of those substances termed bitumens. 



Having here distinguished this process, for the first time, as a 

 species of fermentation, its right to such a distinction ought to be 

 ascertained as soon as possible ; but as the circumstances on which 

 its claim depends are to be found in the history of the phenomena 

 it produces, and of the results of its operation, we will first hasten 

 to their consideration. 



In a process carried on in the recesses of the earth, or, at least, 

 in situations from which our observations are excluded, it is not to 

 be expected, that a complete history of all the phenomena which 

 occur during the whole of the operation can be possibly made out. 

 To furnish a satisfactory account, we must have recourse to infe- 

 rence and analogy ; thus aided, we may, I trust, with only the pro- 

 duct of the operation before us, be enabled to form well-founded 

 conjectures on the phenomena which have actually taken place. 



Almost all vegetable matters manifest a strong disposition to de- 

 composition, when the separation of their integrant molecules is 

 aided by the interposition of the particles of water ; and particularly 

 if, with this, is combined the powerful energy of caloric. If this 

 latter agent be employed, only in a low degree, an intestine mo- 

 tion among the integrant molecules takes place, the equilibrium 

 by which that particular mode of composition was preserved is 

 broken, a separation of the constituent principles takes place, they 

 become influenced by new attractions, and then enter into new 

 combinations and modes of existence. By this process, the fer- 

 mentative process, a resolution of the original compound is effected, 



