POTTERY AND PORCELAIN.

fitted to the ware and fastened by slip. Then the vessel
is smoothed and finished and sent to the " green room
to dry.
CashnSg.-This process consists in filling a hollow
mould, which is divided into two parts and held together
by a strap, with liquid clay or slip, which is allowed to
stand the proper length of time and then emptied out.
The porous plaster having absorbed a portion of the mois-
ture from the slip, which is in direct contact, retains a thin
shell the exact shape of the mould, which in a short time
can be readily removed. In the manipulation of large
vessels, where the weight of the shell would cause it to
fall out when the mould is turned over to empty the slip,
a method has been devised in Europe for forcing com-
pressed air into the interior of the mould to take the place
of the slip as it passes out, and thus hold the shell in place.
By the method of casting, mould seams are partially
avoided and a greater uniformity of thickness and even-
ness of surface are obtained. Thin wares, such as Bel-
leek china, are usually made by the casting process.
KILNS.
The construction of pottery and porcelain kilns, or
ovens, as they are usually termed in England, has changed
but little in the past fifty years. They are conical struc-
tures, built solidly of red brick, with a lining of fire-brick,
and are generally about sixteen feet in diameter inside,
and about the same in height to the crown or ceiling,
above which the walls are narrowed and drawn upward
like a chimney to furnish a draft for the fires. The ex-

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