In dealing with walls the division can be planned in accordance with architectural proportions, but the orthodox features are not necessarily employed. In some phases of traditional decoration much use has been made of pilasters--the spacing and distribution of which, while conforming to the conditions of the interior, are similar to the usual employment of pilasters in exterior architecture, with the difference that the spaces between them are occupied by panels or other features. Except in apartments of unusual height, pilasters should not be mounted on a pedestal; though a pedestal-like feature is often introduced in the form of a Dado or surbase. In such a scheme the entablature also should be used so that the cornice forms a bed moulding for the ceiling. Coupled pilasters may also be employed, and in [Illustration: No. 186. Wall Division. A. & B. Pilaster Treatment. C. & D. Alternation of wide and narrow panels. ] some well-known instances are placed wider apart than is ordinarily the case, and the space between is then occupied by a narrow panel. [Illustration: No. 187. Detail of Ceiling. Library of S. Lorenzo, Florence. M. Angelo.] In smaller apartments the pilaster may be dispensed with, but the division of the wall surface can conform to the same general plan both vertically and horizontally. In the absence of pilasters the spaces may be divided into panels alternately narrow and wide. _Ceilings_ When the ceiling is divided the dividing ribs or beams should bear some relation to the general construction, though in the past this rule has not always been strictly adhered to. For example, the ceiling may very desirably be divided into equal squares or rectangles by means of wooden or plaster mouldings, leaving the enclosed spaces plain or decorated. When mouldings are used these may be enriched, but contrast should be maintained between the framing ribs and the panels. [Illustration: No. 188. Detail of Inlaid Floor. Library of S. Lorenzo, Florence. Repeating general pattern of ceiling.] The Late Tudor decorated ceiling often had narrow moulded ribs geometrically arranged with pateræ in between and fleur-de-lys details on the outer angles where the ribs met. [Illustration: No. 189. Ceiling of Library of S. Lorenzo, Florence. Plan of general arrangement.] [Illustration: No. 190. Late Tudor Ceiling. Littlecotes Hall, Wilts.] _Jacobean_ In the later Jacobean style the rib was replaced by floral bands projecting comparatively slightly and enclosed by narrow borders. These bands were disposed in various ways--sometimes intersecting at right angles and enclosing rectangular or square panels, sometimes forming geometric curves occasionally interrupted by straight lines. If any of these methods of breaking up the surface be employed, it is obvious that the general proportions must be taken into account. _Carolean and Georgian_