EUROPEAN PORCELAIN TO END OF 18TH CENTURY From the time of its first appearance in Europe, at the latest in the 15th century, Chinese porcelain was regarded by potters as in the highest degree woi thy of imitation. Admiration for its whiteness led to the use of a white enamel or slip-covering on the earthenwares of Italy and other countries, whilst its translucency and vitrified texture misled the potters into supposing that a sub stance of the nature of common glass entered into its composition. Attempts to imitate it in this way were made in small manu factories at several places—as at the glass-making centre of Venice and elsewhere in Italy, more particularly at Florence, where a factory was started under the patronage of Francesco de' Medici, not later than 1581. Medici porcelain was decorated, as a rule in a soft blue only, with motives drawn from Italian maiolica in combination with Chinese elements imitated from wares of the type made for export to Persia. The manufacture is supposed to have been continued at Pisa; later and not dis similar porcelain is to be attributed to Candiana near Padua. No settled manufacture was, however, in existence bef ore the latter part of the 17th century. Edme Poterat of Rouen and his son Louis were granted a privilege in 1673, whilst another factory founded in 1677 at St. Cloud near Paris had by the end of the century grown to considerable size. These artificial porcelains, fired at a low temperature and made translucent with the aid of a previously fired glassy mixture or frit, were of the type now known as soft-paste (pate tendre). They remained the character istic porcelains of France for nearly a hundred years, and some what similar compositions were widely used in England, Italy and Spain during the 18th century.
Meanwhile in Germany the insight of Tschirnhausen and Bottger (see below) had perceived that porcelain of Chinese type could be made only with potters' materials, and by experiments with the fusing of clays were discovered, first, a hard red stone ware, and in 1709 true, that is, hard-paste, porcelain, which is essentially a high-fired mixture of the fusible and non-fusible silicates of alumina, called by the Chinese petuntse and kaolin, and in English china-stone and china-clay. From the manufac
ture founded at Meissen upon Bottger's discovery sprang others making hard-paste at Vienna and other places in Germany, at Ven ice, St. Petersburg and Hard-paste began to be made at Sevres in 1769 but did not en tirely displace the pate tendre un til the beginning of the 19th century. In England hard-paste was independently rediscovered before 1768, but it was used in a single manufacture only and was superseded towards the end of the i8th century by a universally-adopted hybrid composition in which china-clay was partially replaced by the ashes of calcined bones, an ingredient which had for some time previously been used in a characteristic type of English soft-paste.