Sprimont, who after all is perhaps the most interesting figure in the history of English porcelain, was after the year 1761 constantly interrupted by ill-health, and the outturn of the kilns was for several years very irregular; finally in 1769 the remaining stock was sold by auction. The next year, the contents of the factory, the moulds, the models--in wax, brass, or lead--the mills and the presses were purchased privately by Duesbury _en bloc_, greatly to the disappointment of Wedgwood, who had his eye upon certain of the models. Duesbury also took over the lease of the Chelsea works, and carried them on conjointly with his main factory at Derby until the year 1784. In that year, on the expiration of the already prolonged lease, the factory at Chelsea was finally abandoned and the kilns pulled down. The sales which had previously taken place at Burnsall’s in Charles Street, Berkeley Square, were now held at Mr. Christie’s ‘in his great room, late the Royal Academy, in Pall Mall.’ It was there that ‘Messrs. Duesbury and Co.’ disposed at intervals of the produce of the combined works. But the history of Chelsea porcelain as a _genre_ apart comes to an end with the departure of Sprimont. During the remaining years of their existence, the Chelsea works formed merely a dependency of those at Derby. As to the marks used at Chelsea, of the early incised triangle, which was formerly ascribed to Bow, we have already spoken. The anchor in relief on a raised oval cartouche (PL. E. 69) is found on relatively early ware; it is associated with a waxy, translucent paste, and a simple decoration without gilding. The mark, _par excellence_, of Chelsea is the red anchor (PL. E. 70), but on richly decorated pieces, and especially those with much gilding, the anchor is often inscribed in gold. BOW.--From the beginning of the eighteenth century to the year 1744 there is no trace of the issue of any English patent relating to the manufacture of porcelain. In the latter year, however, a specification was registered according to which Edward Heylyn, of the parish of Bow, merchant, and Thomas Frye, of the parish of West Ham, painter, professed to make porcelain, by mixing with ‘an earth the produce of the Cherokee nation in America, called by the natives Unaker,’ a glass composed of flint and potash. This unaker, no doubt a kind of kaolin (we are told that the sand and mica had to be carefully washed away), was much talked of at this time (especially in Quaker circles), and its use preceded by some years that of the Cornish china-clay. Possibly something resembling porcelain was made at Bow for a short time with these incongruous materials; but in the winter of 1748-49 a second patent [Illustration: Plate XLIV. _Chelsea. Coloured enamels._]