The
piston is replaced in the box; pressure is again applied to the lever, and
so on. When the line of tiles reaches the end of the table, we lower a
frame on which brass wires are stretched, and cut it into the usual
lengths."

[Fig. 44 - CHEAP WOODEN MACHINE.]

Fig. 44 - CHEAP WOODEN MACHINE.

The workmen must attend well to the degree of moisture of the clay which
is put into the machine. It should be dry enough to show no undue moisture
on its surface as it comes out of the die-plate, and sufficiently moist
not to be crumbled in passing the edge of the mould. The clay for small
(thin) tiles must, necessarily, be more moist than that which is to pass
through a wider aperture; and for the latter there may, with advantage, be
more sand in the paste than would be practicable with the former.

After the tiles are cut into lengths, they are removed by a set of
mandrils, small enough to pass easily into them, such as are shown in Fig.
45, (the number of fingers corresponding with the number of rows of tiles
made by the machine,) and are placed on shelves made of narrow strips sawn
from one-inch boards, laid with spaces between them to allow a free
circulation of air.

[Fig. 45 - MANDRIL FOR CARRYING TILES FROM MACHINE.]

Fig. 45 - MANDRIL FOR CARRYING TILES FROM MACHINE.

*Drying and Rolling.*--Care must be taken that freshly made tiles be not
dried too rapidly. They should be sheltered from the sun and from strong
winds. Too rapid drying has the effect of warping them out of shape, and,
sometimes, of cracking the clay. To provide against this injury, the
drying is done under sheds or other covering, and the side which is
exposed to the prevailing winds is sometimes boarded up.

For the first drying, the tiles are placed in single layers on the
shelves. When about half dried,--at which time they are usually warped more
or less from their true shape,--it is well to _roll_ them. This is done by
passing through them a smooth, round stick, (sufficiently smaller than the
bore to enter it easily, and long enough to project five or six inches
beyond each end of the tile,) and,--holding one end of the stick in each
hand,--rolling them carefully on a table. This operation should be
performed when the tiles are still moist enough not to be broken by the
slight bending required to make them straight. After rolling, the tiles
may be piled up in close layers, some