XIX 



THE RIFT VALLEY AND ITS LAKES 



IN the preceding chapter it was stated that the Rift 

 Valley consists of a western and an eastern arm ; along 

 the floor of each there is a chain of lakes. When 

 these lakes are compared with each other an ex - 

 animation of their contours shows that there are two 

 kinds : some, like the Albert Nyanza and Tanganyika, 

 are long and trough-like ; others are rounded, like Lake 

 Naivasha. The long and narrow lakes resemble fiords 

 witli high precipitous sides. Such are often called 

 cistern-lakes. The best examples of this kind lie in the 

 western arm of the Rift Valley, and include Lakes 

 Albert, Albert Edward, Kivu, Tanganyika, and Nyasa. 



The Lake Chain in the eastern arm of the Rift Valley 

 concerns us most. In this set we have Lakes Naivasha, 

 Elementeita, Nakuru, Baringo, Rudolf (Basso Narok),and 

 many .smaller collections of water in the valley which 

 have received distinctive names. At the southern end 

 of its eastern arm the floor of the Rift Valley has an 

 altitude of 2,500 feet. It rises gradually as it extends 

 northward to the equator ; at Naivasha the floor of the 

 valley is 6,300 feet above sea-level : it then falls to 

 3,325 at Lake Baringo, and Lake Rudolf is only 1,250 

 feet above the level of the sea. 



L<(L-<' Xdirasha. This lake, situated at an altitude 

 of G,300 feet, was discovered by Fischer (1883). 

 The lake is somewhat quadrilateral, twelve miles 

 long and nine broad : it is comparatively shallow. The 

 \\ateris supplied by the Rivers Gilgil and Murundat. 



943 R 2 



