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 is a great
manifestation of subterraneous fire, and of exerted force.
The strata in this space consist, in general, of sand-stone, coal,
lime-stone or marble, iron-stone, and marl or argillaceous strata, with
strata of analogous bodies, and the various compositions of these. But
what is to the present purpose is this, that, through all this space,
there are interspersed immense quantities of whinstone; a body which is
to be distinguished as very different from lava; and now the disposition
of this whin-stone is to be considered.
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