On the Porcelain Clay, €s'c. 405 
Halkin mountain a bed of remarkably fine porcelain clay, which, 
on exposure to the potters’ fires, was found to assume a more 
delicate whiteness than any substance of a similar nature hitherto 
found in this kingdom; and seeing also other substances which 
he thought likely to be useful to the potters, he obtained from 
Ear] Grosvenor a lease of all clays, rocks, and stones (except 
limestone) within his lordship’s liberties; and subsequently, 
with a view to an extended trade, formed his present partner- 
ship with Mr. Richard Fynney, Mr. William Bishop, and Mr, 
James Whitehead, established under the firm of the ‘*-Welsh 
Company at Nant y Moch, near Holywell,’? where they have 
erected works for preparing the clay, which is called ‘* Cambria,” 
for sale, by separating it from a white siliceous sand and rock, 
with which the bed is found mixed to a depth at present un- 
known, but which has been proved as deep as 26 yards. The 
sand, when separated, is used for glass-making; and the white 
siliceous rock, now called ‘‘ Rock Cambria,” is ground down 
and used in the composition of china and earthenware, instead 
of ground flint, or is mixed with it. For this process of grind- 
ing, several thousand tons of chert are annually consumed in the 
Staffordshire potteries, and much is supplied from Halkin moun. 
tain. In quarrying this chert, some of it in the state of vesicu- 
lar entrochital horn-stone was raised, which, when used together 
with common chert, indicated such a superiority by its expedi- 
tious grinding and its little wear, and showed such a proximity 
in appearance (after having been worked) to the French buhr, 
that its use for grinding wheat was considered probable ; and 
this led to the first application of the vesicular Halkin rock as a 
buhr-stone. 
Halkin Mountain (called *¢ Alchene” at the Conquest, accord~ 
ing to Pennant) is a range of high uncultivated land in Flint- 
shire, the mineral property of the right honourable Earl Grosve~ 
nor. On the inland side it runs parallel to the boundary hills 
of the vale of Clwyd; and on the north-east stretches from 
Holywell for about four miles till nearly opposite Northop, in 
an angle of about twelve degrees with the river Dee, and aver- 
ages about a mile in breadth, It is composed of mountain lime- 
stone, with the usually accompanying rocks, and abounds with 
large veins containing lead ore, blende, and calamine, with some 
appearances of copper; it also affords a rock of a whitish quartz, 
well adapted for certain kinds of mill-stones, for which (accord- 
jng to all our old historians) Flintshire has been famous. But 
these quarries had been neglected for many years, till lately re- 
opened by the discoverers of the still more valuable buhrs, and 
promise to regain their celebrity as gray stones for grinding 
oats, &c, 
The 
