Almost due east of the Beit el Khalîfah there rises out of the middle of the plain a large artificial mound, Tell ’Alîj.[138] It is surrounded by a moat, and beyond the moat there are traces of a circular wall. A little to the east of north a raised causeway leads down from the top of the tell, crosses the moat by what must once have been a bridge and runs straight as an arrow over the space between moat and wall [Illustration: FIG. 160.--SÂMARRÂ, STUCCO DECORATION.] [Illustration: FIG. 161.--SÂMARRÂ, STUCCO DECORATION.] [Illustration: FIG. 162.--SÂMARRÂ, FRAGMENT OF POTTERY.] [Illustration: FIG. 163.--SÂMARRÂ, FRAGMENT OF POTTERY.] [Illustration: FIG. 165.--ABU DULÂF, ARCADE.] [Illustration: FIG. 166.--ABU DULÂF, NICHED PIER OF NORTHERN ARCADE.] (Ross made it 110 paces) and across the plain for about half-a-mile. It ends at a low mound where Ross found remains of brickwork. On either side of the point where the causeway reaches the outer edge of the ditch, a low mound, fanning out from the causeway, stretches from ditch to rampart. These mounds are the remains of walls that protected the causeway. Local tradition says that the moat was fed with water by a canal from the Tigris; Ross adds that the ḳanât, or cut as he calls it, brought water from a channel (he uses the word tunnel, by which he probably means ḳanât, underground conduit) which ran from the Jebel Ḥamrîn to Sâmarrâ. What this singular fortified mound can be I do not know, but I should be surprised if it did not belong to a period earlier than the days of the Abbâsids. All the area of the city is strewn with Mohammadan potsherds, but the pottery is markedly different in character from that of Raḳḳah. Coloured ware, though it is not entirely absent, is rare; by far the greater number of pieces are unglazed and ornamented only with incised patterns which are frequently divided into zones by raised notched bands. I saw, too, a few fragments of a better class of pottery with beautiful patterns or inscriptions in relief, worked with the utmost care. When the peasants discovered that the patterned clay excited my interest they brought basket loads of broken pots to my tents and I drew and photographed innumerable examples, two of which I here reproduce (Figs. 162 and 163). In the mosque of Abu Dulâf (Fig. 164)[139] the arcades are carried on massive brick piers and the effect of the long, half-ruined aisles is very imposing (Fig. 165). The area embraced by the outer wall of sun-dried brick is slightly smaller than at Sâmarrâ (213·20 × 136·50 m.) and the arcades are more widely spaced, but the type of plan is the same, even to the spiral minaret to the north. Although the enclosing wall is no better than a crumbling mound, it is possible to make out the [Illustration: FIG. 164.--ABU DULÂF.]