About ½ mile inland a large and deep canal runs parallel to the river. This whole tract is entirely deserted, and, from its appearance, it seems probable that it was thrown out of cultivation prior to the rebellion of 1884. Four miles south of Wad Habashi is the boundary between the provinces of Berber and Khartoum, the limits being marked by the isolated granite hill on the east bank, known by the name of “Hagar El Asal.” From this point, the reefs forming the tail of the Shabluka Cataract begin, and navigation at low water becomes impossible for steamers.[29] Although the actual cataract, or rapid, is only some 12 miles in length, the bad water, above and below the pass, extends for a length of some 55 miles, _i.e._, to Wad Ramla, or to within 35 miles of Khartoum. In summer, _i.e._, if the railway is not used, this portion of the journey has either to be made in native boats, or by camel portage round the cataract. The land route is shorter than that by the river, being not more than 26 miles in length. [Sidenote: Wad Hamed.] Five miles above Wad Habashi the former cavalry station of Wad Hamed is passed on the west bank. This place was selected as the headquarters of the Egyptian cavalry on account of the good fodder to be found in the vicinity. From here the difficulties of navigation increase; the river is split into numerous channels, and winds between picturesque islands, covered with a luxuriant growth of vegetation. Rocks and reefs appear above the water, and the swirls and eddies indicate the existence of many more below the surface. It was in this part of the rapid, on Mernat Island, that the “Bordein” steamer went aground on returning from Khartoum in 1885. Low serrated granite ridges confine the river on either side. At the entrance of the Shabluka gorge, the channel takes a very sharp turn to the east, and the section is both deep and narrow—not being more than 200 yards in width anywhere, and in some places even less than this. The river runs between high granite hills for some 4 or 5 miles, with a very high velocity. The marks upon the rocks show that the highest flood level is not more than 7 feet above the water level of the river in March.