Chap. 1 3.] Ckineje Porcelain. 81 



wards expofed a fecond time to the fire, by which 

 means the glaze it has imbibed is melted, and a thin 

 glaffy coat is formed upon its furface, which is more 

 or lei's yellow, according as a greater or lefs propor- 

 tion of lead has been ufed. 



Porcelain, or china, is a femivitwfre'd earthen 

 ware of an intermediate nature between common 

 wares and glafs. The firit Ipecimens of this beau- 

 tiful manufacture came from China and Japan. Chi- 

 hefe porcelain is faid to be compofed of two ingre- 

 dients, one of which is a hard ftone or rock called 

 ^etuntfe, which they carefully grind to a very fine 

 powder ; and the other, called by them kaolin, is 

 a white earthy iubftance, which they mix intimately 

 with the ground petuntfe. Reaumur examined both 

 thefe matters; and having expofed them feparately 

 to a violent fire, he difcovered that the petuntfe 

 had fufed without addition, but that the kaolin had 

 given no fign of fufibility; from which it appeared 

 that the former was of a flinty nature, and the latter 

 argillaceous. He afterwards mixed thefe matters, and 

 formed cakes of them, which, by being baked, were 

 converted into porcelain fimilar to that of China. 

 Macquer thinks that the firft European porcelains 

 were made in Saxony and in France; and afterwards in 

 England, Germany, and Italy. Manufactories have 

 jfmce been eftablifhed in almoft all the countries of 

 Europe, in many of which porcelain is made very little 

 if at all inferior to the Chinefe. 



III. Lithomarga, or STONE-MARROW, when dry, 

 feels as ilippery as foapi but is not wholly diffufible in 

 wafer. When mixed with water, it falls in pieces, 

 fo as to afibme the appearance of curds. In the fire 

 \t melts into a frothy flag. In the mafs it breaks into 



VOL. II, G irregular 



