261 
A revision of the several circumstances mentioned w^hilst de- 
scribing the situation of coal, and its accompanying strata, w^ill serve 
not only to confirm the supposed origin of coal, but also to prove 
the fact of its having at one time existed in a fluid state. The dif- 
ferent partings, as they are termed, between the top of the coal 
and the roof, deserve particular notice, on this account. In good 
partings there sometimes exists a space between the coal and roof, 
the coal being sprinkled with a powder like charcoal. In this case 
the previous fluid state may be surely inferred without the least 
difficulty, the space appearing to be the consequence of the drying 
and contraction of the matter forming the coal, and after the superior 
stratum, the roof, had acquired a considerable degree of firmness. 
This inference must be made, almost without hesitation, in other 
instances, where the parting is perfectly clear •, the head of the mass 
of coal being described, by writers on this substance, as possessing a 
surface so smooth and polished, as if it had been varnished, or 
covered by some fluid matter. 
In confirmation of coal having existed in a state of fluid bitumen 
(petroleum), I must remark that this substance is frequently found 
in the neighbourhood of coal. Thus Mons. Morand, who thought 
that bitumen was probably the basis of coal, informs us, that in the 
mines of Tranche Compte, the bitumen exudes in the form of a sort 
of guhr (tears of the mines). 
That the wreck of the vegetable part of the antediluvian world 
was placed in such a situation as to be continually permeated by 
water, and subjected to the conversion into bitumen ; and that the 
nascent bitumen would unite with, and afterwards retain, a portion 
of this water, I have not, indeed, been able to present you with 
actual proof; but have been only able to olfer you evidence of a 
circumstantial nature : which I, however, trust is of some con- 
siderable weight. 
