purpose for which our author gave it, it would refute his
supposition, as certainly as the example which I have given.

So far I have reasoned upon the supposition of this alkali, with its
water of crystallization, being truly a mineral concretion; but, I see
no authority for such a supposition: It certainly may be otherwise;
and, in that case, our author would have no more right to give it as an
example in opposition to Dr Black's argument, than he would have to give
the crystallization of sea-salt, on Turk's Island, in opposition to the
example which I had given, of the salt rock, at Northwych in Cheshire,
having been in the state of fusion.

It certainly was incumbent on our author to have informed us, if those
masses of salt were found in, what may be properly termed, their mineral
state; or, if the state in which they are found at present had been
produced by the influences of the atmosphere, transforming that saline
substance from its mineral state, as happens upon so many other
occasions; I am inclined to suspect that this last is truly the case.
It may be thought illiberal in me to suppose a natural philosopher thus
holding out an example that could only serve to lead us into error, or
to mislead our judgment with regard to those two theories which is the
subject of consideration. This certainly would be the case, almost
on any other occasion; but, when I find every argument and example,
employed in this dissertation, to be either unfounded or misjudged,
Whether am I to conclude our author, on this occasion, to be consistent
with himself, or not?

I have but one article more to observe upon. I had given, as I thought,
a kind of demonstration, from the internal evidence of the stone, that
granite had been in the fluid state of fusion, and had concreted by
crystallization and congelation from that melted state. This no doubt
must be a stumbling block to those who maintain that granite mountains
are the primitive parts of our earth; and who, like our author, suppose
that "things may have been originally, as at present, in a solid state."
It must also be a great, if not an invincible obstacle in the way of the
aqueous theory, which thus endeavours to explain those granite veins
that are found traversing strata, and therefore necessarily of a
posterior formation.

To remove that obstacle in the way of the aqueous theory, or to carry
that theory over the obstacle which he cannot remove, our author
undertakes to r