30 SEMIVITRIFICATION. [H. 



Porcelain was made at Jersey City in 1816, and a successful 

 establishment was conducted at Philadelphia for some years, 

 but closed in 1836. Stone-ware of good quality is made in 

 many places, especially in New York, Philadelphia, and Bal- 

 timore, but it is not yet equal in quality to the Lambeth-ware 

 of London. We believe the location 'is yet to be found, 

 where many potteries can gain a permanent foothold ; the 

 first essential being bituminous coal ; the next, good clays in 

 some abundance ; and the third, facility of communication by 

 water or railroad. The finer qualites of clay and feldspar 

 will bear transportation, and may even be obtained on our 

 seaboard, from Devonshire, &c., England, at about the same 

 cost as they are in the Stafibrdshire potteries. The most 

 likely position for a potting district is in western Pennsylvania, 

 or on a few points on the Ohio or Missouri rivers, where the 

 first and greatest essential, fuel, is abundant. 



There are few novel points of interest in these arts, which 

 we present below. The general principles of painting and 

 staining glass and clay-ware are so similar that they may be 

 treated together, although we have separated them for con- 

 venience. 



Fire-clay from fusible clay. — Gaffard gives the following 

 method of effecting this result. (L'Institut, No. 594, p. 175 ; 

 Berz. Jahresb. 1846, 293.) A good quality of clay, but not 

 fire-clay, is mixed to a paste with muriatic acid, and, after 

 some time, heated to boiling. The acid is run ofi", and the 

 clay fully washed and dried. Clay, thus treated, was made 

 into crucibles, in which bar-iron was fused, without their be- 

 coming softened by the heat. The acid simply extracts a 

 large proportion of those bases (lime, iron, &c.) which tend 

 to flux the principal part of clay, the silica and alumina; but 

 the question of economy will influence the use of this remedy 

 for the fusibility of clay, and it is doubtful whether the pro- 

 cess will be adopted by manufacturers. 



Porcelain. — An interesting series of experiments has been 

 made by Dr. WJichter in Berlin, in which he ignited various 

 mixtures of feldspar and kaolin, and, in connection with Dr. 



