[Illustration: No. 263. Wood Inlay. Simple silhouette.] _Veneer, Marquetry_ In Veneer work and in Marquetry, where the work is quartered and juxtaposed, the interest consists in the patterning of the figured woods, particularly when these are arranged to form reciprocal shapes. _Boule Work_ The interest of Buhl or Boule work, an inlay of metal employed in the French Renaissance in the decoration of furniture, often in conjunction with tortoiseshell, is that of contrast of texture. [Illustration: No. 264. Italian Intarsia. Forms elaborated by incised lines.] In the design, profile or silhouette is the primary consideration, being used: 1. As a form of framing, 2. In angles or centres on table-tops, 3. In panels in furniture: [Illustration: No. 265. Louis XV Cabinet with Ormolu Mounts. Marquetry, veneer quartered and inlaid with floral detail. (Photo: V & A Museum).] [Illustration: No. 266. Boule Work. Period of Louis XVI.] The design can invariably be complete within the area. Coloured grounds are employed as well as tortoiseshell. _Mosaic_ Mosaic designs may be complete in themselves or be the result of repetition, according to attitude and purpose, and with regard to variety and colour, only restricted by æsthetic considerations. [Illustration: No. 267. Boule Work. Period of Louis XVI.] Owing to technical limitations, modelling can only be broadly suggested; therefore forms should be generally in silhouette except when on a large scale. When employed on walls and vaults, gold is frequently used in the backgrounds. This not only serves to define detail, but affords contrast to the general surface, the inevitable joints in the tessaræ adding also to the interest. _Byzantine Use of Marble_ Associated with Mosaic decoration in the Byzantine Period was the employment of marble in shafts of columns and for lining walls by banding or slabbing, frequently quartered, so as to display the markings in reciprocal forms. Such marbles were chosen for figuring and colour, the former in its variety being an important factor in the surface interest. Similar employment of slabs occurs in the treatment of floors, where contrast in colour is the chief consideration. It is sometimes associated with Mosaic of small tesseræ, also in marble, whereas that used on walls and in vaults was frequently of glass. The foregoing is a broad summary of ornamental expression in the Flat, with the exception of Book Decoration. _Book Decoration_ In Black and White, which is chiefly employed, the designs may be in tone or line with suggestion of rotundity or relief; or line decoratively employed, according to subject, or purely decorative. The same applies to renderings in colour. Designs for covers are controlled by the processes involved, whether printed, stamped or tooled. [Illustration: No. 268. Mosaic Borders. A. From Carthage. B. & C. Withington, Gloucester.] [Illustration: No. 269. Mosaic Border, Roman.]