Porcelain is composed of two ingredients, one of which--kaolin--is infusible, and the other--petuntse--vitrifies, and envelops the kaolin. It is translucid, and therein differs from pottery, which is opaque. As to the origin of the word, we have already seen that it was, in its Italian form, applied to majolica in the sixteenth century; and the word “pourcelaine” occurs two centuries earlier. It was used to designate Oriental china in the fifteenth century. Mr. J. F. Davis, in his work on the Chinese (1840), quotes Marsden to the effect that the word “porcelain,” or _porcellana_, was applied by Europeans to the ware of China, from the resemblance of its fine polished surface to that of the univalve-shell so named; while the shell itself derived its appellation from the curved or gibbous shape of its upper surface, which was thought to resemble the raised back of a _porcella_, or little hog. When porcelain was first invented in China is not exactly known. The combination was discovered in the province of Honan about eighteen hundred years ago; but the date cannot be more specifically fixed. From China it was introduced into Persia, Egypt, and Barbary, at a very early period, and was thence imported into Europe, where, however, it was not generally known until 1518. The first specimens of Oriental porcelain known to have reached England were given by Philip of Austria to Sir Thomas Trenchard, of Wolverton, in 1506. To continue its history in Europe, it is necessary to observe that there are two kinds of porcelain--the natural, or _pate dure_, and the artificial, or _pate tendre_. The latter cannot stand so high a temperature as the former, and can be scratched with a knife, which the hard porcelain resists. The soft-paste was the first to be discovered in Europe. Chemists, struck with the beauty of the Chinese porcelain, and impelled by a desire to imitate, began to experiment in the sixteenth century; and the first success, of which substantial evidences now exist, was gained at Florence in 1580. It is said that a Venetian potter made porcelain sixty or seventy years earlier; but no specimen known to be his is now in existence. After that of Florence, the next discovery was made by Dr. Dwight, of Fulham, England, in 1671; and in 1695 the secret was penetrated by M. Chicanneau, at St. Cloud, France. By that time the Florentine porcelain and process had been forgotten, and the English and French ceramists pursued perfectly independent investigations. The problem of making a hard-paste porcelain resembling that of the Orient still remained unsolved. No chemistry could avail the experimenters so long as the materials were wanting. To the accidental discovery of a bed of kaolin, Europe owed its first hard porcelain. This important event took place about the year 1709, and the circumstances leading to it are full of interest.