on
of the world which he has thus attacked; and I wish that he or any
person would point out, in what respect I had demanded any thing
unreasonable, or any thing that is not actually to be observed every
day.

Thus I have endeavoured to show, that our author has attacked my theory
in a part where I believe it must be thought invulnerable; but this is
only, I presume, in order that he may make an attack with more advantage
upon another part, viz. the composition of strata from the materials of
an earth thus worn out in the service of vegetation,--materials which
are necessarily removed in order to make way for that change of things
in which consists the active and living system of this world. If he
succeed in this attempt to refute my theory of the original formation
of strata, he would then doubtless find it more easy to persuade
philosophers that the means which I employ in bringing those materials
again to light, when transformed into such solid masses as the system of
this earth requires, are extravagant, unnatural, and unnecessary. Let us
then see how he sets about this undertaking.

With regard to the composition of the earth, it is quoted from my
theory, that _the solid parts of the globe are in general composed
of sand, gravel, argillaceous and calcareous strata, or of various
compositions of these with other substances_; our author then adds,
"This certainly cannot be affirmed as a fact, but rather the contrary;
it holds only true of the surface, the basis of the greater part of
Scotland is evidently a granitic rock, to say nothing of the continents,
both of the Old and New World, according to the testimony of all
mineralogists." This proposition, with regard to the general composition
of the earth, I have certainly not assumed, I have maintained it as a
fact, after the most scrupulous examination of all that, with the most
diligent search, I have been able to see, and of all that authors
have wrote intelligibly upon the subject. If, therefore, I have so
misrepresented this great geological fact on which my theory is
absolutely founded, I must have erred with open eyes; and my theory
of the earth, like others which have gone before it, will, upon close
examination, appear to be unfounded, as the dissertation now before us
is endeavouring to represent it.

Our author here, I think, alleges that the contrary to this, my
fundamental proposition, is the truth; and he has given us Scotland as
an example in which