hat those arguments of his, with regard to the difficulty or
impossibility of procuring that fire, can only show the error of his
reasoning. I am far from supposing that my theory may be free from
inconsistency or error; I am only maintaining that, in all his confident
assertions, this author has not hitherto pointed any of these out.

So far I have answered our author's objections as to consolidation, and
I have given a specimen of his reasoning upon that subject; but with
regard to my Theory of the Earth, although simple fluidity, without
heat, would have answered the purpose of consolidating strata that had
been formed at the bottom of the sea, it was necessary to provide a
power for raising those consolidated strata from that low place to the
summits of the continents; now, in supposing heat to be the cause of
that fluidity which had been employed in the consolidation of those
submarine masses, we find a power capable of erecting continents, and
the only power, so far as I see, which natural philosophy can employ
for that purpose. Thus I was led, from the consolidation of strata, to
understand the nature of the elevating power, and, from the nature of
that power, again to understand the cause of fluidity by which the rocks
and stones of this earth had been consolidated.

Having thus, without employing the evidence of any fire or _burning_,
been necessarily led to conclude an extreme degree of heat exerted in
the mineral regions, I next inquire how far there are any appearances
from whence we might conclude whether that active subterraneous power
still subsists, and what may be the nature of that power. When first I
conceived my theory, naturalists were far from suspecting that basaltic
rocks were of volcanic origin; I could not then have employed an
argument from these rocks as I may do now, for proving that the fires,
which we see almost daily issuing with such force from volcanos, are a
continuation of that active cause which has so evidently been exerted
in all times, and in all places, so far as have been examined of this
earth.

With regard to the degree of heat in that subterraneous fire, our
author, after proving that combustible materials would not burn in the
mineral regions, then says, that suppose they were to burn, this would
be "incapable of forming a heat even equal to that of our common
furnaces, as Mr Dolomieu has clearly shown to be the case with respect
to volcanic heat." The place to which he al