682 | GEOLOGY OF OHIO. 
its ordinary glaze, and is then sprinkled or “spaddled” with the 
manganese glaze; this, on burning, colors the otherwise clear glaze 
to a beautiful brown, running to black. “Self-Rock” or brown-ware is 
made by the use of a manganese glaze over the whole surface, instead 
of sprinkling it. This outline was taken mainly at the works of Cart- 
wright Bros., at Liverpool, where the industry can be seen at its best 
advantage, but visits to other works of the same sort have given ad- 
ditional range to the description. 
The manufacture of earthen-wares in Ohio in 1882, according to 
available statistics, amount in value produced to $419,028.00, distributed 
in the main over 4 counties, but in a few isolated works beside. 
WHITE-WARE OR IRON-STONE CHINA. 
This business is centered in two places in the State, Hast Liverpool 
and Cincinnati, but Liverpsol has very much the greatest development. 
The manufacture of white-ware began in 1873, and was an outgrowth 
of the yellow-ware manufacture which had for years been carried on there 
in great quantity. The materials used are all imported into Ohio; the 
kaolin beds of Chester county, Pennsylvania, Maryland, Maine, Dela- 
ware, Indiana, Missouri, Virginia, South Carolina, are all represented, 
each establishment using from two to five kinds of clays. The 
ball clays used in the cheaper white-ware, or “C. C.,” comes from New 
Jersey and Missouri. The saggers used in the white-ware manufacture 
are made from Woodbridge clay, New Jersey. ‘The flint is made from 
the beautiful, clean white sand, which comes from the clay washings of 
Delaware. It is pulverized in a revolving barrel half-full of black flint 
pebbles. The spar comes from the quarries in Maine; it is calcined,. 
broken up and ground in pans, the bottom of which are lined with French 
buhrstone, and on which revolve heavy pieces of buhr attached by 
chains to revolving arms. By this device, which bears a remarkable 
resemblance to the crude gold mills in use in Mexico, a very fine state 
of division is attained. 
The main distinction between the yellow and white-ware manufac- 
ture is in the preparation of the clay “body”. This “body” or mixture 
of clays, flint and spar, to be used in the molds, is the great secret of each 
establishment. Usually not more than one or two men in the works 
know it, and frequent transactions are made by which a recipe for a 
