THE TANGANYIKA PROBLEM. 7 



unite together in the region of the Upper Nile. Thence 

 they pass to the Red Sea near Berbera, and continue as 

 the valley of this sea itself as far as the Gulf of Acabah, and 

 even through the Dead Sea to the valleys of the Jordan. 

 In the western arm of these great valleys and north of Tan- 

 ganyika there lie the lakes Kivu, the Albert Edward and 

 the Albert Nyanzas. After returning from the first Tan- 

 ganyika expedition, none of these more northerly lakes were 

 zoologically known, nor had the remaining great African 

 lakes, the Victoria Nyanza and the chain of lakes in 

 association with Rudolf, been sufficiently minutely examined 

 to show whether the halolimnic fauna existed in them or not. 

 When, therefore, we took into account the fact that both 

 the great series of valleys united and extended as far as the 

 Red Sea, it appeared on the face of it, at least possible that 

 the halolimnic fauna, or something equivalent to it, would be 

 found in the lakes north of Tanganyika, whenever these 

 lakes came to be zoologically explored, and that the western 

 series of valleys might itself turn out to be the channel 

 alono- which the sea had reached the lake. Moreover, the 

 districts north of Tanganyika through Lake Kivu, as far as 

 the Albert Nyanza, and including the Mountains of the 

 Moon, were an almost complete terra incognita from a geo- 

 graphical point of view. A large stretch of this country was 

 uncharted, and thus a further journey offered exceptional 

 opportunities for geographical work in the hands of a com- 

 petent surveyor. It was this aspect of future exploration in 

 these regions which gave them a distinctly geographical 

 interest, and enabled the proposal of a second Tanganyika 

 expedition to be supported by the promise of a very liberal 

 grant from the Royal Geographical Society. Such an 

 expedition was thus to be recommended on zoological, on 

 geological, and on geographical grounds, and these three 



