KERAMIC STUDIO 
39 
by the use of grog. Grog is the potters' name for burned 
clay, broken pottery and the like which is crushed to 
small fragments. Grog is troublesome to prepare but no 
artist who desires perfect work will grudge the labor. 
When a beginning has been made in the production 
of pottery there is never any lack of broken pieces. These 
may be of the ordinary red clay or of any other clay, in 
fact if there be not enough at hand broken bricks will 
answer quite well but whatever is used it must be biscuit, 
not glazed. An ordinary pestle and mortar will do with 
which to crush the pieces and two sieves must be procured 
one of sixteen meshes to the inch the other of thirty-five 
or forty meshes. The pounded pottery is sifted through 
the coarser on to the finer and then the dust is sifted through 
the latter so that the resulting grog is what will pass through 
a sixteen and lie upon a forty or, as described in brief, 
16-40 grog. 
The dust is sifted out because if it were not it would 
render the clay too short for use. It is not possible to 
say exactly how much grog is to be added to the clay for 
no two clays are quite alike as regards plasticity. Gen- 
erally speaking the dry clay and grog are about equal in 
weight, making about three parts of grog to two of dry 
clay by measure. To insure a repetition of results some 
such proposition should be weighed or measured and 
the mass then worked up with water. The clay should 
first of all be crushed and sifted through the sixteen sieve. 
The working of the mixed material will prove the best 
guide, the rule being to add all the grog that the clay will 
bear. The more the better so long as the mixture be 
plastic enough to be worked. The clay and grog as pre- 
pared should be rather soft, a little softer than would be 
used for building or throwing. 
And now to make the tiles. It is presumed that 
they are to be perfectly plain and not embossed. Any 
embossement must be prepared in the model. 
The clay is rolled out into a sheet a little thicker than 
the proposed tile and from this sheet blank tiles are cut 
with ruler and knife of the exact size of the mold. If 
true sharp edges are expected these blanks must drop 
cleanly into the molds and yet fit closely. One of the 
blanks is transferred to a smooth plaster bat and the face 
of it is polished with a steel blade. A long kitchen knife 
will do. If the polishing presses down the edges as it is apt 
DECORATIVE ROSE, SECOND PRIZE— MARY OVERBECK 
