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the river. Between Dufile and Fort Berkeley many rivers flow into 
the Albert Nile. The Asua, the Atappi, the Umi, the Karpetu, the 
Kweh and many others from the right bank bring down water in flood 
well laden with sand. In the dry season all but the Asua are dry. 
The left bank tributaries are numerous but insignificant. The volume 
discharged by these streams in the rainy season is very considerable, 
as will be seen if the discharges at Gondokoro north of Fort Barkeley 
are compared with those at Wadelai. They are between them capable 
of increasing the discharge of the Albert Nile for short intervals of 
time by 1500 cubic metres per second. All these streams are torrential. 
They rise and fall quickly. 
From Fort Berkeley to Khartoum, the Albert and White Niles are 
navigable. 
From Fort Berkeley to Bor past Gondokoro on a length of 
206 kilometres the Albert Nile falls some 18 metres and has a good 
velocity and slope, and though the river is divided into two and more 
channels, it is within its banks and may be considered an ordinary 
river. The maximum discharge is about 2600 cubic metres per second 
and the minimum 550. In high floods the river scours out its bed 
and sides very considerably. The real flat lands begin at Gondokoro a 
little to the north of Fort Berkeley. The soil is light and sandy and 
capable of offering little resistance to the stream. Between Gondokoro 
and Bor the Albert Nile can lose some 30 per cent of its discharge 
when the river is high and capable of overflowing most of the islands 
and a great part of the valley. The main channel has a width of about 
230 metres and depth of 3 or 4 metres when the discharge is below 
600 cubic metres per second and well within banks. The main 
tributaries of the Albert Nile in this reach are on the east bank, the 
Kit, second only to the Asua, and the Lokadero ; and on the west bank 
a number of unimportant torrents which however help to swell the 
river in flood. 
From Bor to Ghaba Shambe on a length of 196 kilometres, the main 
stream of the Albert Nile flows between banks lower than those further 
south and more heavily inundated in flood, with a width of some 60 
metres and depth of water of 5 metres. According to Sir William 
Garstin, the grass swamps end half way down this reach and the 
papyrus swamps begin. About 10 kilometres to the east of the main 
stream is another branch known as the Atem river fed by artificially 
maintained and natural spills from the main stream itself. These spills 
