solution, or if they appear to have been congealed from the melted state of their aqueous fusion.—­Has he ever thought of this?  Now this is so material a point in the view with which that example has been held out to us, that, without showing that this salt had crystallised from the solution, he has no right to employ it as an example; and if, on the other hand, it should appear to have simply congealed from the state of aqueous fusion, then, instead of answering the 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.