The principal varieties of this ware are the grey and white “Canette” of Siegburg, near Bonn, and the pale brown or grey ware of Raeren, near Aix-la-Chapelle, with its incised and stamped enrichments, sometimes with blue decoration. Frechen, near Cologne, probably supplied the “Bellarmines” or “Grey beards,” largely imported into England under the name of “Cologne Pots.” Examples of this Frechen ware were frequently ornamented with a raised scroll of oak leaves. Grenzhausen, in Nassau, produced a beautiful grey ware, having delicately moulded reliefs filled in with blue and purple. Many grey jugs ornamented with the initials of William III., Queen Anne, and George I., were imported into England from the Nassau kilns. A peculiar kind of stoneware, also termed “Cologne ware” was produced at Fulham by John Dwight, about 1670. Some fine jugs and a few cleverly modelled unglazed statuettes, believed to have been made at this place, are to be seen in the British Museum (fig. 11). Another peculiar red stoneware, porcelain, or Red China as it was called, was made near Burslem by the Brothers Elers, 1688-1710, the ornamentation being obtained by pressing sharp intaglio copper moulds upon pieces of clay attached to the shaped ware. Fine examples, characterised by beauty of outline and delicacy of enrichments are exhibited in the Museum of Geology, Jermyn Street. Astbury, 1710-39, continued the traditions of Elers, producing a fine white stoneware, which largely influenced the Staffordshire pottery of that period. A stoneware was also made at Nottingham from 1700 to 1750. Porcelain is technically known under the terms “hard paste” (“pâte dure”) and “soft” (“pâte tendre”). Hard porcelain is made from clays containing much aluminia and felspar or decomposed granite, having but little plasticity, which necessarily influenced the shape or profile of the vessel. The beauty of form, which is so typical of the Greek earthenware vase, is absent in porcelain, where the cylindrical or octagonal form is principally used. “Pâte tendre” is a soft and vitreous porcelain, having a great affinity for the beautiful coloured glazes and enamels used in the early examples of Sèvres. Porcelain was known in China about 200 B.C., and it was in common use during the 16th century. During the Ming dynasty, 1568-1640, porcelain reached its highest development in the perfection of its body, ornamentation, colour and glazes, blue and turquoise being the chief colours of this period; this limited range of colour was owing to the intense heat required to fuse the felspar glaze upon the hard porcelain.