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plants and trees ; and such we well know is v|he appearance which 

 is yielded by peat in certain periods of its formation. This mass, 

 then, of decayed leaves and roots of plants, and of trees, as described 

 by the ingenious observer, was undoubtedly a mass of long buried 

 vegetable matter, part of a stratum of peat, passing through the bitu- 

 minous fermentation ; and which had become covered with water. 

 The opportunity of its separation had doubtless been given, by the 

 superincumbent strata having been so reduced by the excavation 

 which formed the lake, as not to leave a sufficient thickness and 

 strength to resist the expansive powers of the gaseous matters ; and 

 these, by their extrication, had separated the mass, which, from 

 its lightness, floated on the water. 



That this bituminous fermentation was actually going on may be 

 reasonably inferred, from the nature of the gas which was expelled ; 

 its peculiar odour, and its imputed inflammability, strongly denot- 

 ing the presence of hydrogen ; the separation, and the subsequent 

 fixation pf which have been assumed as important steps in this pro- 

 cess. Another circumstance yields very strong collateral evidence, 

 that this operation had proceeded to a certain length. The specific 

 gravity of all bituminous substances is, generally, less than that of 

 the vegetable matter from which they have been formed ; this is 

 most certainly the case, when wood has suffered this species of 

 conversion. As this process has therefore gone on, the substance 

 has become specifically lighter, and cavities have been formed by, 

 and distended with, the detached hydrogen, which must have also 

 increased the levity of the mass, and enabled it, even with the 

 superincumbent earth, to make its ascent through the water. 



It may also be remarked, that the eruption of these gaseous mat- 

 ters in considerable quantities is sufficient to account for the agita- 

 tion of the waters, and for the other phenomena which are described 

 as appearing to have been produced by some powerful, elevating 

 force, applied underneath. 



