y the melted bodies flowing in the subterraneous
chimney; whereas, at the bottom of the ocean, the contact of the water
necessarily tends to close the orifice, by accumulating condensed matter
upon the weakest place.

If this be a just theory of the natural operations of the globe, we
shall have reason to expect, that great quantities of this melted
matter, or fusible substance, may be found in form of lava, among the
strata of the earth, where there are no visible marks of any volcano, or
burning mountain, having existed. Here, therefore, is an important point
to be determined; for, if it shall appear that much of this melted
matter, analogous to lava, has been forced to flow among the strata
which had been formed at the bottom of the sea, and now are found
forming dry land above its surface, it will be allowed, that we have
discovered the secret operations of nature concocting future land, as
well as those by which the present habitable earth had been produced
from the bottom of the abyss. Here, therefore, we shall at present rest
the argument, with endeavouring to show that such is actually the case.

It appears from Cronstedt's Mineralogy, that the rock-stone, called trap
by the Swedes, the amygdaloides and the schwarts-stein of the Germans,
are the same with the whin-stone of this country. This is also fully
confirmed by specimens from Sweden, sent me by my friend Dr Gahn.
Whatever, therefore, shall be ascertained with regard to our whin-stone,
may be so far generalized or extended to the countries of Norway,
Sweden, and Germany.

The whin-stone of Scotland is also the same with the toad-stone of
Derbyshire, which is of the amygdaloides species; it is also the same
with the flagstone of the south of Staffordshire, which is a simple
whin-stone, or perfect trap. England, therefore, must be included in
this great space of land, the mineral operations of which we explore;
and also Ireland, of which the Giant's Causeway, and many others, are
sufficient proof.

In the south of Scotland, there is a ridge of hills, which extends
from the west side of the island in Galloway to the east side in
Berwickshire, composed of granite, of schistus, and of siliceous strata.
The Grampians on the north, again, form another range of mountains of
the same kind; and between these two great fields of broken, tumbled,
and distorted strata, there lies a field of lesser hardness and
consolidation, in general; but a field in which there i