Cornish China Clay . 
501 
1 877J 
Potteries, and which is the chief constituent of all the por- 
celain or finer sorts of earthenware, is obtained wholly from 
the county of Cornwall and the adjoining district of Dart- 
moor. It is the purest or most highly esteemed description 
of the clay known, and may be called the mainstay of our 
English manufacture, without which we could not possibly 
hold our pre-eminence over other nations in the excellence 
of our products, and in a commercial point of view the china 
clay trade of Cornwall has a much greater importance than 
has hitherto generally been supposed. 
The application of Cornish china clay to the purposes of 
pottery is due to the enterprising spirit of William Cookworthy, 
of Plymouth, whose persevering efforts in the cause of the 
ceramic art are only surpassed by those of Josiah Wedgwood, 
the “ founder,” or rather great improver, of the Staffordshire 
potteries. Mr. Cookworthy opened a pottery at Plymouth in 
1733,* and probably used at first only the inferior clays of 
Dorset and Devon. Owing, however, to the meagre infor- 
mation that is now extant about Cookworthy’s labours, the 
date when he discovered the china clay, or first applied it 
to any practical use, cannot be accurately ascertained, but 
from his travels through Cornwall as a chemist, and his 
peculiar aptitude for geological research, its existence is 
likely to have been known to him long before he thought of 
turning it to account. Possibly, too, he may have used the 
clay for some time privately, reserving his knowledge from 
the public until some favourable opportunity occurred of 
divulging it, in accordance with that jealous spirit of secrecy 
so characteristic of discoverers in the eighteenth century. It 
appears to have been about the year 1755 that he found a 
stone at St. Stephen’s, Cornwall, which he proved to be 
identical with the Chinese petuntz, or as it is now called 
china stone, f used for forming the glaze on porcelain, and 
which is the felspar of granite in a less advanced stage of 
disintegration than when considered as “ clay.” From a 
short account of the life of Cookworthy, published by his 
grandson,! it appears that “ he first found china clay and 
stone at Tregoning Hill, then in the parish of St. Stephen’s, 
and afterwards in the domain of Boconnoc, the family seat 
of Thomas Pitt, nephew of the Earl of Chatham, and after- 
wards Lord Camelford.” In 1768 Cookworthy, in company 
* See a small pamphlet entitled Relics of William Cookworthy, by John 
Prideaux. London : Whitaker and Co., 1853. 
f This was the first time that china stone was found in Europe. 
t Memorials of Wm. Cookworthy by his Grandson, with an Appendix, 
London ; 1854, Also another Appendix published in 1S73. 
