[ 54i ] 
ftrata, yet,- by the form and roundnefs of their 
trunks, they muft be, in a great meafure, encom- 
pafled by the foil, in which they are buried ; whereas 
there is not the lead: mixture of earth, or any other 
aperture, in the Bovey ftrata of coal, except a few 
crevices, common to this fort of foffil, which divide 
the pieces from each other in all directions, and feem 
to be inconfiftent with the nature and fibrous texture 
of wood. 
If the balls or matrix of this foffil were wood, it 
Would acquire, by being impregnated with bitumen, 
a greater degree of inflammability ; whereas it neither 
kindles nor confumes fo fall as wood. 
The inflammability and laminated texture of this 
foffil, which have been the only reafons for fuppoflng 
it of vegetable origin, may be accounted for from the 
nature of its principles, and their difpofition, when 
united, to aflume certain forms. The bituminous 
matter uniting with various kinds of earth, in certain 
proportions, will form an inflammable fubftance ; and 
a fimilar mixture of thefe will generally aflume a 
flmilar texture and form, as will appear from the ac- 
counts given us of this foffil both by the antients 
and moderns, moll: of whom fpeak of it as a mineral 
fubftance. 
Theophraftus * mentions <c a ftone on the pro- 
€{ montory of Erineas in Peloponefus, and another 
“ in the mines of Binae in Thrace, which being 
<f burnt, emitted a bituminous odour j and another 
" ftone in the mines of Scaptilulae, not unlike to rotten 
* De Lapidibus, p. 4. 
4A 1 
cc 
wood, 
