d
in a variety of ways among those strata, then deeply immersed at the
bottom of the sea; and, _lastly_, That they have been there congealed
from the state of fusion, and have remained in that situation, while
those strata have been removed from the bottom of the ocean to the
surface of the present land.

To describe those particular appearances would draw this paper beyond
the bounds of an essay. We must, therefore, refer those who would
inquire more minutely into the subject, to examine the chalk-countries
of France and England, in which the flint is found variously formed; the
land-hills interspersed among those chalk-countries, which have been
also injected by melted flint; and the pudding-stone of England, which
I have not seen in its natural situation. More particularly, I would
recommend an examination of the insulated masses of stone, found in
the sand-hills by the city of Brussels; a stone which is formed by an
injection of flint among sand, similar to that which, in a body of
gravel, had formed the pudding-stone of England[7].

[Note 7: Accurate descriptions of those appearances, with drawings,
would be, to natural history, a valuable acquisition.]

All these examples would require to be examined upon the spot, as a
great part of the proof for the fusion of the flinty substance, arises,
in my opinion, from the form in which those bodies are found, and the
state of the surrounding parts. But there are specimens brought from
many different places, which contain, in themselves, the most evident
marks of this injection of the flinty substance in a fluid state. These
are pieces of fossil wood, penetrated with a siliceous substance, which
are brought from England, Germany, and Lochneagh in Ireland.

It appears from these specimens, that there has sometimes been a prior
penetration of the body of wood, either with irony matter, or calcareous
substance. Sometimes, again, which is the case with that of Lochneagh,
there does not seem to have been any penetration of those two
substances. The injected flint appears to have penetrated the body
of this wood, immersed at the bottom of the sea, under an immense
compression of water. This appears from the wood being penetrated
partially, some parts not being penetrated at all.

Now, in the limits between those two parts, we have the most convincing
proofs, that it had been flint in a simple fluid state which had
penetrated the wood, and not in a state of solution.

_Fir