10. =The Victoria Nile.=--From the Ripon Falls to Lake Albert, the Victoria Nile has a length of 400 kilometres. The first 64 kilometres are down a steep slope, in a stream varying from 300 to 500 metres in width. Any project for a regulator at the Ripon Falls should contemplate development of electricity for working a railway along these 64 kilometres. The next 237 kilometres are through a flat marshy land, partly lake, partly swamps, but with the water never more than 4 to 6 metres deep. In this reach the Nile is navigable. This many-armed swamp is known as Lake Choga, whose western end is traversed for some 80 kilometres by the Nile with a perceptible current. These large sheets of papyrus and water, which cover an area of over 2000 square kilometres, must cause as much loss by evaporation as they receive by direct rainfall. The Victoria Nile leaves the lake in a broad stream some 900 metres wide, past Mruli station, on to Fowera. In the longitudinal section on Plate II, I have considered Fowera as 1060 metres above sea level, and the slope upstream of it as ¹⁄₂₀₀₀₀. From Fowera to the foot of the Murchison Falls, the Nile falls 377 metres on a length of 68 kilometres, and then in the next 30 kilometres reaches Lake Albert. Considerable quantities of floating pistea weeds pass down the Victoria Nile from Lake Choga. They are well churned up between Fowera and the Murchison Falls, but finally enter Lake Albert. It would be easy to develop electricity to work a railway along these 68 kilometres. [Illustration: PLATE IV. CROSS SECTIONS of the NILE & its TRIBUTARIES _Horizontal Scale 1 : 2.000_ _Vertical Scale 1 : 600_ Lith. Sur. Dep. Cairo. No. 1. _Victoria Nile upstream of Ripon falls_ No. 2. _Kagera River within 10 km. of mouth_ No. 3. _Semliki River about 50 km. upstream of Albert Lake_ No. 4. _Albert Nile at Wadelai._ No. 5. _Asua River about 2 km. above junction with Nile._ No. 6. _Albert Nile at Gondokoro._ No. 7. _Albert Nile at Mongalla_ No. 8. _Albert Nile above Lake Nô_ No. 9. _Bahr el Ghazal 51 km. from mouth_ No. 10. _Bahr el Zeraf 20 km. from mouth_ No. 11. _Albert Nile 4 km. above junction with Sobat_ No. 12. _Sobat River at Doleib Hills_ No. 13. _White Nile 14 km. below Taufikia_] The principal tributaries of the Victoria Nile are the following:-- On the right bank, the Gogonia, the marshy Kwania and Lenga, and the Duki. And on the left bank; the lake-like Sensiwa; the Kafu with its numerous feeders, large catchment basin but generally insignificant discharge; and the Titi. The Uganda rivers are more like sponges than rivers, and in all probability the tail of the Victoria Nile has a discharge only slightly in excess of that at the head.