TILES are stone, metal or composition slabs for use in covering a roof to keep out the water. Since the most common material is baked clay, and this same clay is used to form drain pipe, the word tile has been extended in meaning to cover clay pipes termed drain-tile. This same baked clay is often colored and fused on one side, giving it a glazed finish often of great beauty. Such colored and glazed tiles are used for interior walls, dados, floors, man tles, etc. Drainage tiles are made of native clay and usually glazed inside. Each tile has at one end an extended rim which overlaps the small end of the tile next to it, thus forming a continuous pipe. Roofing tiles take the form either of flat shingle or slate-like slabs or of pantiles. A section through a pantile shows a horizontal-like curve, one side of the tile being concave and the other convex — the latter curve fitting over the concave curve of the next tile, and so on. In this manner there is no opening left open to the weather. The same principle is often applied to the flat tiles and to ridge tiles, ixhich bear on one edge a semi-circular convex hp, and on the other a concave one. Ridge tiles are made in angles to fit and cap the ridge-pole of a roof, to turn corners and to ornament pro jections. Roof tiles are glazed or dull, accord ing to the maker's fancy, and are used in varie ties of colors. Modern taste seems to prefer either highly glazed saffron or terra-cotta pantiles, or else dark dull flat ones. But dur in.g the Renaissance and until recent years highly colored glazed roof tiles either in the flat or corrugated style were in large demand throughout southern and central Europe. Fine examples of decorative roof,s are preserved from the Middle Ages, a notable instance being the roof ot Saint Stephen's Cathedral in Vienna. Such tiles are often enameled and are thus rendered waterproof. Slate, marble and metal roof-tiles are occasionally employed.
Interior tiles are made in great varieties of shapes and sizes, colors and materials, ranging from fine brick-clay tiles to those of enameled and painted porcelain. They are used for
pavements, flooring and revetments to walls. Old houses in the south of Europe were com monly paved with red brick-tiles baked hard and sometimes glazed. The method of decora tion usually employed was to inlay clays of different colors in the bodies of the tiles, pro ducing designs often of great beauty. Enameled tiles were used in the 15th and 16th centuries for the pavings of interiors of importance, such as chapels, chambers of honor, etc. These thin, enameled tiles broke easily and only a few examples are to-day preserved in the cathedrals and castles of France and Italy. The use of tiles for wall revetments and for dados was not general during these periods but has grown in recent years. Modern wall tiles are usually painted or glazed and are of various fine clays, not infrequently of porcelain. Large wall spaces are covered with painted tiles in pic torial or decorative composition, the work of Theodore Deck affording some fine examples. Tiles with slightly raised figures are also used, the style having been borrowed from the Per sians who are masters of their manufacture. A recent effective use of colored clay tiles may be seen in the subway stations in New York, where especially pleasing effects have been in expensively produced by the judicious selection and blending of colors. Modern usage does not follow the example of the Middle Ages in the employment of carved and leaded marble tiles. In these latter the variously shaped slabs of stone were incised with intricate and elaborate designs and the incisions filled with lead or colored compositions and sometimes with fine mosaic work. Consult Church, W. A., (Patterns of Inlaid Tiles,' etc. (1845) ; Herdtle, H., Worlagen fiir das polychrotne Dach ornament' (1885); Jones, Owen, 'Designs in Mosaic and Tessellated Pavements,' etc. (1842); Monceaux, Henri, 'Les cart elages histories du moyen-ige et de la renaissance,' etc. (1887); Wallis, Henry, (Italian Ceramic Art,' etc. (1902) and the papers of Ricardo, H. R., on 'Architect's Use of Enameled Tiles' (in The Archilectural Review for 1902, Vol. XI).