As the entablature was in all probability entirely constructed of wood, and has disappeared without a trace, the restoration of this part of the building is difficult. But the normal forms may yet be determined with greater correctness than is presented in Coste’s restoration (_Fig._ 82), which is a tasteful combination of the scotia and roundlet cornice common to both Egyptian and Assyrian architecture, with dentils and the leaved ornaments found above all the doors and windows of Persian remains, and with the decorations upon the borders of staircase buttresses. A number of rock-cut tombs appertaining to the early Persian kings, the Achemenidæ, and dating from the time of Darius, represent the façades of royal palaces, and give important information concerning the exterior appearance of such structures. The oldest and best-preserved of these is designated by cuneiform inscriptions as the tomb of Darius. (_Fig._ 83.) It is especially interesting as illustrating the formation of the entablature. An epistyle, triply stepped, like that of the Ionic style, so that each face slightly projects beyond the one beneath it, is placed above the transverse beam, which lies upon the backs of the double-headed animals forming the capitals of the columns. The multiplication of the faces of the epistyle is explained by the weakness of the timber produced by Mesopotamia and Persia, which, in opposition to the single and massive Doric lintel-block, required the employment of several beams to obtain the desired capability of support. Upon it followed the ornaments known as dentils, representatives of the small and closely lying joists of the horizontal, slightly projecting roof. They are quite similar to the dentils upon the tombs of Beni-hassan, and to those of the still more naïve imitations of wooden houses found in Lycia, which will be considered in the following section.
In Persia, the proportions of the dentils and of the distances between them are still characteristic of the original timbered construction--a truthfulness of imitation which was lost as early as the development of the Ionic style. The nature of the band following above is not clear; it might be natural to suppose in it a representative of such a hollow cornice with leaves as Coste has introduced upon his entablature, were it not that a frieze-relief with ornamental lions is visible upon this member in another tomb, and that a remarkable block of the Palace of Darius at Persepolis bears further testimony against it. One of the corner piers of the front portico of that building has been preserved to such a height that the side bearing of the lintel can be observed. This renders the projection and outline of the entablature certain. It was six times stepped, and may best be reconstructed, as in _Fig._ 84, by a series of narrow bands, which represent in some measure the layers of the horizontal ceiling and roof. From a comparison with the rock-cut tomb, it is plain that a further cornice, like that over the door and window-frames, was here not possible. If a parapet had been desired for the accessible platform of the roof, it must have taken the form of a light balustrade, not that of a heavy scotia cornice.