The building of the candlestick is started, like the bowl in the first problem, by coiling from the centre, and the rim may be added in the same way. Care should be taken, however, to attach the central tube firmly. This may be coiled or simply modelled from a single lump of clay. If there is to be a handle it is well to build it at the time the central tube is built, as it is then easier to make a firm attachment.
PROBLEM: TILES
The varied and extensive uses of tiles make it difficult to limit the scope of this problem. Tiles are used for paving, wall facings, ceilings, coverings for stoves, linings and facings for fireplaces, rests for flower pots and teapots, and for various other purposes. Tiles figure very prominently in the history of art. They are objects of interest and study in many public buildings and museums throughout the civilized world. But this problem will confine itself to two of the many varieties of tiles, viz., tiles designed for bowls or teapots and tiles used for the facing of fireplaces.
A tile frame
The Tile Frame.—In building tiles a frame is used measuring about 6 inches square by 5⁄8 of an inch thick. The strips forming the frame may be 1 inch wide, lightly nailed together at the corners so that, if necessary, the frame can be easily taken apart while the clay is moist. This frame is placed on a plaster bat or piece of paper and the clay forced firmly into its corners and sides, working toward the centre, until the frame is completely filled. It is then turned over in order to make sure that the under side of the clay is thoroughly welded together. Care should be taken to use sufficient clay to bring both surfaces well up to the surface of the frame, scraping off the surplus clay with a straight edge. While the clay is moist, one side is chosen for the back, and this is hollowed out to prevent warping. The hollowing may take the form shown in the right-hand tile at the top of [Plate XIV], or it may be in the shape of channels 3⁄4 of an inch or more in width, separated by ridges 1⁄2 of an inch wide running across the back of the tile. Whichever method is used, the depth should be about 3⁄16 of an inch and not over 1⁄4 of an inch. Even when the utmost precaution is taken, the tile is very liable to warp. It should therefore be dried slowly and with the greatest possible evenness of exposure on both sides. The greatest help of all is found in the use of the so-called "grog." This is made by grinding to a powder clay that has been fired once and shrunk, but not glazed. It is used by mixing it with the clay before it is moulded, in the proportion of one part grog to three of the clay. It may be added here that grog will be found of great assistance not only in making tiles but in making other ware. It will not be necessary, however, to burn clay for the express purpose of making grog. The occasional failures which develop at the first firing of every batch of pottery will furnish an adequate supply.
Tiles
[Plate XIV]