XVIII 
THE CRATERS OF THE RIFT VALLEY 
Soon after leaving the Island of Mombasa by the 
Uganda Railway, the traveller will realise that he is in 
a volcanic district. The brick-red earth and the char¬ 
acter of the rocks exposed in the railway cuttings 
indicate that the soil is the result of the disintegration 
of lava. All doulits on this matter will be removed 
when passing through the forest regions north of 
Nairobi, the train suddenly conies to the edge of the 
Kikuyu escarjmient, and he looks directly into the Rift 
^hllley, one of the most remarkable physical features of 
Eastern Ethiopia. 
In order to appreciate the character of the Rift Valley 
it is necessary to realise that the British East Africa 
and Uganda Protectorates represent an area of some¬ 
thing more than 500,000 square miles. The coastlands 
of this enormous territory are low : on leaving the coast 
the land rises in a series of plateaus until a lu'oad zone 
of high ground is reached, varying in height from 6,000 
to 8,000 feet. This zone is often spoken of as the 
Highlands of East Africa. This high plateau, which 
presents remarkable evidence of stupendous volcanic 
action, is furrowed by a gigantic trench known as the 
Rift Valley. Projecting around the margins of this 
high tableland there are three enormous mountains 
crowned with perpetual snow : Kilimanjaro (19,321 ft.) 
in German Territory; Ruwenzori (16,619 ft.) on the 
Congo side ; and Kenia (17,000 ft.) in the east. There 
are isolated smaller mountains such as Elgon, Longonot, 
226 
