reddlfli brown, and fometimes in thin
layers perfectly tranfparent. * It is worked
at an expence of about two {hillings a
ton.
To draw up the rock fait, they have
fire engines, equal in power to three horfes.
It is chiefly exported under a heavy duty ;
and in the town are .fifty or fixty officers
of excife.
Common fait is procured by difiolving the
rock fait, and if a fine fort be required, a
ftrong fire is made under the brine, and the
fait forming at the top, precipitates to the
bottom. I f flronger fait be wanted, as for
fifh, &c. the heat is adminiftered flowly,
when the fait cryftallizes in large cubes.
The whole furrounding country is clay,
and very coarfe grit; and wherever a fhaft
is funk in the neighbourhood, there is a
certainty of finding fait.
The
The "grit ftone prevails as far as the
town of Flint in the county fo called ; and
as no coal is found near Northwich, it is
prefumable that the fait is above it.
In the county of Flint, and near the capital
of that name, are plenty of coal mines
at various depths.
Towards Conway there is abundance of
limeftone, and at Newmarket I obferved
fome heaps of green calamine.
Llandidno is fituated on the top of a
hill, and is a poor village. The copper
mine is in limeftone, and feems to occupy
a large fpace ; the'furface has funk feveral
yards, the bottom being foft, and containing
caverns, with calcareous fpar and copper.
This mine is faid to have been worked
by the Romans, and feems to lie in bunches.
There are fome curious calcareous fpars;
and the limeftone is very full of chert.
Fine mala&ites, of the velvet kind, have
m 3 been