For a detailed discussion concerning this apparently unique service see Geoffrey A. Godden, Chamberlain-Worcester Porcelain 1788-1852, pp. 194-6 and pls. 30 and 238 - 41; also Caughley & Worcester Porcelains 1775-1800, Introduction pl. K. Cf. a sugar-bowl and cover from the collection of Geoffrey Godden sold in these Rooms on 13 February 1989, lot 110