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CHAPTER V. 
THE GEOLOGICAL TOPOGRAPHY OF THE REGION NORTH OF 
TANGANYIKA TO THE ALBERT NYANZA. 
It has been seen that the eurycolpic folds in the more 
southern portions of Equatorial Africa, those in which lie 
Nyassa, Shirvva, Mwero, Rukwa and Tanganyika, constitute 
a series of depressions which have arisen as phenomena 
subordinate to the formation of the Great Central African 
Range. It is further probable, from existing observations, 
that the more northern and eastern series of valleys, 
those in which Rudolf, Stephanie and Beringo are found, 
have arisen in a similar manner. This more eastern series, 
from some way south of Beringo to Basso- Norack, has, 
up to the present time, been far better known than the 
much greater and more western series of folds, which 
contain Tanganyika, and extend beyond it to the Albert 
Nyanza on the Nile. The explorations of Thompson, 
Teleki, Stuhlmann and others, have resulted in the 
accumulation of an extensive series of observations relat- 
ing to the more eastern districts. On the other hand, 
the northern continuations of the much broader and deeper 
depressions which hold Nyassa and Tanganyika, had, 
up to the departure of the second Tanganyika expedi- 
tion, never been explored geologically at all beyond 
