After some trials, which resulted either in the production of a kind of opaque glass or stoneware, Watcher or BOttger, an alchemist (who seized by Frederick Augustus II. in 1701), after Schnorr, in 1709, had discovered white kaolin at Aue,'pro duced from it a white hard porcelain at Meissen, near Dresden; and the porcelain estab lislnnent there was founded under, royal auspices. Extraordinary precautions were taken to prevent the process being discovered, by imposing oaths upon the workmen. and the process there pursued was not communicated till 1812 to Brongniart. The secret, however, was betrayed by Stofzel, a workman, of Meissen, who fled to Vienna in 1720, where an imperial establishment was founded, which exists to this day. Other workmen carried the secret from those establishments all over Germany. Royal works were set up at Berlin in 1755, at St. Petersburg in 1744, and at Munich in 1758. From thisperiod, two different kinds of porcelain were made in Europe, a soft and a hard. In France, soft porcelain was made at St. Cloud in 1695, and was not discontinued till 1SO4. Tl.e acci dental discovery, by Mme. afflict, of kaolin at St. Yrieix Is Perche, in 1765, led to the production of hard porcelain at Sevres, where, after 1800, only this kind was made. Various places in France made both kinds; and in Italy, both were produced at La Doccia, near Florence, at Capo di Monte, near Naples, and at Venice. Other establish ments flourished at Madrid and Oporto, established in the 18th century. The manufac ture of soft porcelain appears to have been introduced in England, at Bow, as early as the 17th c., and the Chelsea works were set up still earlier, according to some, by Elers. Thence the art was transferred to Derby in 1748; and an establishment at Worcester, founded in 1751 by Dr. Wall, is said to have first printed on porcelain. Hard porcelain was made by Cookworthy at Plymouth in 1705, and afterward at Bristol, but was sub sequently abandoned as unprofitable, although again made by. Minton in Staffordshire in 1850. One of the last inventions in porcelain has been the introduction of Parian, or statuary, used for the production of small figures and statues, by Copeland and Minton. Among the oriental nations, the production of porcelain seems limited to China and Japan, although fayences and glazed wares are manufactured all over the east. The production of a white porcelain, either soft or hard, capable of being molded and painted with various colors, effected a revolution in the ceramic art: sculptors were employed to mold small figures and other objects by the different establishments, and the vases, which at first were decorated with rude copies or poor imitations of their Chinese originals, by degrees introduced on their surfaces the art of the country where they were made. The paintings on porcelain thus resembled those on enamel, and when the pieces were of considerable dimensions, and painted by distinguished artists, became of great value. Thus, copies of works of Raphael and of Tintoretto, in the exhibition of 1851, were val ued at £1000 and £880. Even ordinary cups, when painted with vignettes, have their value much augmented. So also the application of delicate colors, as blue, green, and added a charm not found in the monochrome glazed ware of the middle ages. For these, Dresden and Sevres were formerly unrivaled; but the colors of late years have been changed, and do not equal the old. The style of art has varied in each century; the old rococo shapes having been superseded at the commencement of this century by classical shapes, and again by modified medieval forms. The present age has been dis tinguished by an attempt to reproduce majolica, palissy, and other wares; by the improve ment of printing in colors; by the invention of statuary porcelain, and an application of the material to other purposes, as buttons, stamped or pressed from a mold or die. Besides the ornamentation of vases, a trade-mark is often added, either stamped in or painted on the ware. This, on the early majolica, had the date, place, and name of the artist; but the Dresden, Sevres, Chelsea, and other establishments introduced devices, monograms, arms, etc., as swords, anchors, crowns, and other devices. The Chinese has devices, mottoes, names of makers, and the date of the reign when made, commenc ing with the first monarch of the Xing dynasty about 1480, generally in red color, and imitating the seals or stamps used for sealing documents. These marks are continued
to the present day.
Brougniart, Traitg des Arts Ceramiques(8vo, Paris, 1844); Birch, Ancient Pottery (1858); Ma•ryat, Pottery (2d 1864); Jacquemart and Le Blant, Histoire de la Porcelaine (1862); Eliza Meteyard, Wetlywood and his Works (1873); the reports of the exhibitions at London (1851-62); Paris (1855-67-78); and Philadelphia (1876).
dough-like condition into which clay can he worked with water, and the hardne5s it may be made to acquire by burning, are qualities which have been turned to account by man from the earliest times, and it is upon these that the potter's art essentially depends; but there is great variety in clay, and it is only by knowing something of its nature and constituents that any real advance has been effected in pot tery. If a piece of clay be examined, it will be found that it consists of exceedingly minute particles, held together by aggregation when moist; but if dried it can be easily reduced to an impalpable powder by mere pressure; and if, instead of drying, we add an excess of water, it may be so mixed and held in suspension in the water that it appears almost ty be dissolved. In time, however, it is deposited as a sediment, anal when the excess of water is removed, it is a soft tenacionA piste, which is so non-elastic that it will retain the smallest impression made in it without change. This minute division of its particles, and the absence of elasticity, are its most valuable qualities. But all clays are not of the same purity and quality; the commonest is that of brick fields, which is one of the most abundant substances in nature; but it is so mixed up with iron and other foreign ingredients that, except for bricks, tiles, and the coarsest kinds of pottery, it is not used.
The purest kinds of potter's clay are called kaolin, and are believed to have been formed by the decomposition of tacks containing,large proportions of feldspar, a slightly variable compound substance, which, in general terms, may be said to be a combination of neutral silicate of alumina and the silicates of potash, soda, lime, or magnesia, together or singly. Certain kinds of granitic rocks, especially the whiter varieties, by their atmospheric decomposition, yield fine kaolin. Great experience is required in selecting and using the materials, because in nature the plastic materials are very irregularly mixed with other substances, which have a more or less deteriorating effect. Most of the best-known clays contain a certain portion of free silica in addition to that in com bination as natural silicate, which requires to he removed for very fine wares by boiling in caustic potash, otherwise, it proves injurious. The finest china-clay of Great Britain i obtained from Cornwall, where the decomposed granite is washed by streams of water, which carry it away into ponds called catch The discovery of this source of china clay was made by Mr. Cookworthy about the middle of last. century, and alone afforded means for improving our native pottery, which were most admirably turned to account by Mr. Josiah Wedgwood, and after him, by Mr. Herbert Minton, Mr. Copeland, and others. Previous to this, although as before noticed, tine pottery was made in Britain in two or tree places, yet the general character of our pottery, which was firefly manu factured in the neighborhood of Bluslem, in Staffordshire, was most mist raffle both in material and design. The clay was inferior in color, prepared with very little care, and covered with a coarse white or yellow lead glaze; but the discovery of the Cornish clay by affording a material of excellent quality, stimulated the manufacturers to improve the general style of their manufacture. Scarcely second in importance to this discovery was' Wedgwood's good taste and untiring zeal in working out that revolution in the art of the British potter, that has led to its present enormous development. In 1730, when Wedg wood was born at Burslem, in Staffordshire, that place supplied the greater part of the common household pottery of Great Britain; but so small was the trade, that it was but little more than a village encumbered with heaps of broken crockery, and its environs disfigured with clay-pits and piles of refuse: now it is the center of a populous district called "The Potteries," comprising about 48 sq. miles. In this limited space there are now nearly 280 kilns at work, employing more than 100.000 operatives.