# Dictionary of National Biography, 1885-1900/Cookworthy, William

​COOKWORTHY, WILLIAM (1705–1780), porcelain-maker, was born at Kingsbridge, Devonshire, in 1705, his mother being left a widow with five sons and some daughters. About the time of the father's death nearly all their property was lost in the South Sea stock speculation. The widow retired to a smaller house, in which she maintained herself and daughters by the most rigid economy. William Cookworthy and his brother eventually started in a small drug business in Plymouth. In this they were so successful that they had their mother to live with them in Nut Street, Plymouth, and were enabled to allow her to be a liberal benefactor to the poor. The brothers appear to have followed the business of wholesale druggists for many years. Although educated by the Society of Friends, Cookworthy did not, until he had reached his thirty-first year, manifest any strong religious feelings. At this time he retired from trade, and after a period of probation he accepted a gift in the ministry, and laboured diligently in the western counties. For about twenty-five years Cookworthy held a meeting in his own house ‘every first day evening when at home,’ as we are informed by the ‘Testimony of Monthly Meeting’ for 1781. A Friend of Plymouth thus described him: ‘A tall, venerable man, with three-cornered hat and bushy, curly wig, a mild but intellectual countenance, and full of conversation. … He used to travel as a wholesale chemist through Cornwall, and at Godolphin was always the guest of Nancarrow, superintendent of mines in that district, who being also ​a scientific person, they used to sit up most of the night engaged in their favourite subjects.’
In a letter written on 5 May 1745 Cookworthy says: ‘I have lately had with me the person who has discovered the china earth. … It was found in the back of Virginia, where he was in quest of mines, and having read Du Halde, he discovered both the petunze and kaolin.’ The first true porcelain manufactured in Europe was made by Böttcher in 1709 at Dresden, and in 1710 he was appointed director of the Meissen factory, and after five years of experiment he succeeded in making the fine porcelain known as ‘Dresden china.’
Cookworthy having seen the kaolin from Virginia (china clay), and the petunze (china stone, or growan stone), he discovered on Tregonning Hill the Cornish china clay, and soon after he noticed that a portion of the granite, or moorstone, of the same district resembled in some respects the petunze, and on exposing it to a white heat in a crucible he obtained ‘a beautiful semi-diaphanous white substance.’ This was the Breage china stone, but, containing black particles which burnt red, it was not fitted for a porcelain glaze. At Carlegges, in St. Stephen's parish, near St. Austell, he found subsequently both the clay and the stone of the desired purity. This appears to have been between 1755 and 1758. The clay and stone found in St. Stephen's was on the property of Lord Camelford, who assisted Cookworthy in his first efforts to make porcelain in Plymouth, the works being established at Coxside. His progress was slow, and it was not until 1768 that he obtained a patent for the exclusive use of Cornish clay and Cornish stone in the manufacture of porcelain. In the Plymouth works from fifty to sixty persons were employed. The company—Lord Camelford being one of the firm—obtained a high-class porcelain painter and enameller from Sèvres. Henry Bone [q. v.] was educated in this pottery
Cookworthy afterwards sold the patent right to Mr. R. Champion of Bristol, who founded a pottery in that city. Neither the porcelain works in Plymouth nor those in Bristol were profitable, and in 1777 the patent right was sold to a company in Staffordshire. Cookworthy brought his chemical knowledge to bear on the porcelain manufacture, and he appears to have been the first chemist who in this country obtained cobalt-blue direct from the ores. A well-known Staffordshire potter writes of Cookworthy's discovery: ‘The greatest service ever conferred by one person on the pottery manufacture is that of making them acquainted with the nature and properties of the materials, and his introduction of “growan stone” for either body or glaze, or both when requisite.’ Cookworthy is said to have been a believer in the dowsing, or divining rod, for discovering mineral veins, and we learn that he became a disciple of Swedenborg. As a Friend he was universally esteemed by the Society; as a minister he was zealous, engaging, and persuasive; as a lover of science he was much appreciated, as is proved by the fact that Sir Joseph Banks, Dr. Solander, and Captain Cook dined with him at Plymouth before their voyage round the world. Cookworthy died on 16 Oct. 1780, aged 76.
[Prideaux's Relics of William Cookworthy, 1853; Testimony of Monthly Meeting, Plymouth, 1781; Polwhele's History of Cornwall; Burt's Review of Plymouth, 1816; History of Staffordshire Potteries, Hanley, 1827; Price's Treatise on Mining; De la Beche's Catalogue of British Pottery and Porcelain.]
R. H-t.