[Illustration: FIG. 5.--TOMB AT ABYDOS.] [Illustration: FIG. 6.--TOMB AT BENI-HASSAN.] +THE MIDDLE EMPIRE: TOMBS.+ The monuments of this period, as of the preceding, are almost wholly sepulchral. We now encounter two types of tombs. One, structural and pyramidal, is represented by many examples at Abydos, the most venerated of all the burial grounds of Egypt (Fig. 5). All of these are built of brick, and are of moderate size and little artistic interest. The second type is that of tombs cut in the vertical cliffs of the west bank of the Nile Valley. The entrance to these faces eastward as required by tradition; the remoter end of the excavation pointing toward the land of the Sun of Night. But such tunnels only become works of architecture when, in addition to the customary mural paintings, they receive a decorative treatment in the design of their structural forms. Such a treatment appears in several tombs at Beni-Hassan, in which columns are reserved in cutting away the rock, both in the chapel-chambers and in the vestibules or porches which precede them. These columns are polygonal in some cases, clustered in others. The former type, with eight, sixteen, or thirty-two sides (in these last the _arrises_ or edges are emphasized by a slight concavity in each face, like embryonic fluting), have a square abacus, suggesting the Greek Doric order, and giving rise to the name _proto-Doric_ (Fig. 6). Columns of this type are also found at Karnak, Kalabshé, Amada, and Abydos. A reminiscence of primitive wood construction is seen in the dentils over the plain architrave of the entrance, which in other respects recalls the triple entrances to certain mastabas of the Old Empire. These dentils are imitations of the ends of rafters, and to some archæologists suggest a wooden origin for the whole system of columnar design. But these rock-cut shafts and heavy architraves in no respect resemble wooden prototypes, but point rather to an imitation cut in the rock of a well-developed, pre-existing system of stone construction, some of whose details, however, were undoubtedly derived from early methods of building in wood. The vault was below the chapel and reached by a separate entrance. The serdab was replaced by a niche in which was the figure of the defunct carved from the native rock. Some of the tombs employed in the chapel-chamber columns of quatrefoil section with capitals like clustered buds (Fig. 7), and this type became in the next period one of the most characteristic forms of Egyptian architecture. [Illustration: FIG. 7.--SECTION AND HALF-PLAN OF A TOMB AT BENI-HASSAN.]