Sudan Angelo-Egyptian ] THE NILE ; CATARACTS 75 a bank ) , 22 miles north of Halfa, whence it flows through Egypt to the sea .

The Cataracts . The navigation of the Nile beyond Khartum is much interrupted by cataracts, of which there are six between Khartum and the sea .

The highest , which is about 52 miles below Khartum , is known as the Sixth or Shabluka Cataract . It has a fall of about 20 ft . , most of which occurs in a little over one mile. 194 miles farther on the Fifth Cataract begins, a little below El Abadia , and about 30 miles below Berber; it is over 100 miles in length, and in this distance the fall is 205 ft . About 60 miles beyond the Fifth Cataract is the Fourth , which is 68 miles in length and has a fall of 160 ft . Between the Fourth Cataract and Kerma, at the commencement of the Third, is a stretch of 200 miles of navigable water, which is the main trade route of the Dongola province. The Third Cataract, which has two rapids, is over 45 miles in length, with a fall of 36 ft .; and about 70 miles farther on is the Second Cataract , 125 miles long , with four rapids , passing through the inhospit able region known as the Batn el-Haggar ( Bellyof Rocks), where the Nile falls 213 ft . Halfa is 6 miles below the foot of the Second Cataract . The First Cataract ( 214 miles from the Second ) is beyond the Sudan frontier, between Assuan and Shellal, and has a fall of 16 ft . in 3 miles. The river passes over the great dam at Assuan ; and , by means ofa fine masonry canal with several locks, navigation is made possible at all seasons of the year from Halfa to the mouth of the Nile at Damietta, a distance of nearly 1,000 miles. During flood season the cataracts are navigable by those who know their peculiarities and dangers, but they are not much used except for local communica tion, the railway being preferred for traffic between Halfa and Khartum .

The Sudd Region .-No account of the Nile and its navigation would be complete without a description of the sudd ( Arabic sadd, meaning a “ block ” ) and the sudd region , that is to say, the huge area of marsh , [ 3919] G