The maximum discharge of the Albert Nile at Hillet-el-Nuer may be taken as 450 cubic metres per second, and into Lake No as 320 cubic metres per second. The water of the river is dark-coloured and contains no sediment. Very little ambatch is met with north of Ghaba Shambe. Between Ghaba Shambe and Lake No on the left bank, in the first 120 kilometres, three channels carrying very appreciable quantities of water flow into the Albert Nile. These are considered to be the tails of the river Yei. At Hillet-el-Nuer, about 170 kilometres north of Ghaba Shambe, a branch takes off from the west side of the Albert Nile, known as Gage’s channel, with 35 metres of clear waterway, 1 metre depth and 0·60 metre per second velocity, discharging 20 cubic metres per second. This stream flows westwards and is lost in the swamps. On the right bank, downstream of Ghaba Shambe, are the two heads of the Bahr Zeraf, one natural and the other artificial made by Sir Samuel Baker. About 90 kilometres north of Ghaba Shambe a few spills take water towards the Zeraf river. [Illustration: PLATE VI. THE ALBERT NILE. FROM GONDOKORO TO THE SOBAT JUNCTION Scale 1 : 2,000,000 Lith. Sur. Dep. Cairo. Part of Albert Nile _South of Sudd No. 15_] From Lake No to the Sobat mouth, on a length of 134 kilometres is the tail reach of the Albert Nile. The Albert Nile flows into Lake No in its south-eastern corner and leaves it on its east side. On the west side the Gazelle river flows into the lake. Lake No has an area of some 20 square kilometres in times of low supply and 100 square kilometres in flood. In low supply the depth is between 1·50 and 2·50 metres. In the reach between Lake No and the Sobat mouth, the river is very fairly straight; the summer channel is about 170 metres wide and as a rule about 5 metres deep upstream of the mouth of the Lolle, though in one place about 8 kilometres from Lake No it becomes only 50 metres wide for a short distance. Between the tail of the Lolle river and the mouth of the Sobat river, the summer width widens out to about 400 metres with 3 metres depth of water. However extensive the marshes may be, the high land forming the limit of the inundation is everywhere in this reach visible from the main stream. The Gazelle river, which flows into Lake No, has a discharge varying from 0 to 40 cubic metres per second. The Lolle river which flows in on the left bank upstream of the Sobat mouth is probably an arm of the Albert Nile or an overflow of the Gazelle and has a discharge varying from 0 to 40 cubic metres per second. On the right bank, the Zeraf river flows into the Albert Nile, with a discharge varying from 30 to 160 cubic metres per second. The Megahid river flows in 30 kilometres below the tail of the Zeraf river and adds an undetermined quota of water.