ness of the country,
across this part of the island, is almost sufficient testimony that it
had been composed of softer materials.

Thus the coal country of Scotland may be considered as in one band
across the island, and included in the counties of Ayr, Lanark, and all
those which border upon the Frith of Forth. Now, in all this tract of
coal and tender strata, we do not find ridges of alpine stone or primary
mountains, but we find many hills of solid rock, little mountains, from
500 to 1000 feet high; such as that beautiful conical hill North Berwick
Law, Torpender Law, Arthur's Seat, the Lowmands, and others of inferior
note. That is to say, the whole of this included space, both sea and
land, has been invaded from below with melted masses of whin-stone,
breaking up through the natural strata of the country, and variously
embossing the surface of the earth at present, when all the softer
materials, with which those subterranean lavas had been covered, are
washed away or removed from those summits of the country. Hence there is
scarcely a considerable tubercle, with which this country also abounds,
that may not be found containing a mass of whin-stone as a nucleus.

But besides those insulated masses of whinstone that form a gradation
from a mountain to a single rock, such, for example, as that on which
the Castle of Edinburgh is built, we find immense quantities of the same
basaltic rock interjected among the natural strata, always breaking and
disordering them, but often apparently following their directions for a
considerable space with some regularity. We also find dykes of the same
substance bisecting the strata like perpendicular veins of rock; and, in
some places, we see the connection of these rocks of the same substance,
which thus appear to be placed in such a different form in relation to
the strata.

It will thus appear, that the regular form, and horizontal direction of
strata throughout this country of coal, now under contemplation, has
been broken and disordered by the eruption and interjection of those
masses of basaltic stone or subterraneous lava; and thus may be
explained not only the disorders and irregularities of coal strata, but
also the different qualities of this bituminous substance from its
more natural state to that of a perfect coal or fixed infusible and
combustible substance burning without smoke. This happens sometimes to a
part of a coal stratum which approaches the whin-stone.

Ha