Formation and General Features of Ruwenzori. 
basin of Lake Ruisamba to the north and upon which are 
situated Toro and Fort Portal; the other branch passes to the 
west of the range and forms the Semliki Valley and the basin 
of Lake Albert, and is prolonged for several hundred miles 
by the upper valley of the Nile. Ruwenzori is thus nearly 
completely surrounded by the “ Albertine Depression,” and forms 
with the three lakes an independent hydrographic system 
absolutely distinct from that of Lake Victoria. 
Thus it is that this Ruwenzori range sheds the waters of 
all its slopes east, west, north and south into one and the 
same, river basin, feeding almost unassisted the three lakes 
and the Semliki, which together form the south-western 
sources of the Nile. Furthermore, Ruwenzori being without 
doubt the most considerable group of snowy mountains on 
the African continent, and situated in the middle of that 
continent, and running in the direction of its main axis, 
does not form a portion of its main watershed. The actual 
watershed between the Congo and the Nile consists of a line 
of low hills, lying at a short distance to the west of the 
Semliki, and masked by the great Congo forest, running 
northward along Lake Albert, prolonged southward in the 
volcanic chain which forms the dividing ridge of the rift, 
between Lakes Kivu and Albert Edward, and finally skirting 
the eastern shores of Lake Kivu and of Lake Tanganika. 
The Duke of the Abruzzi preserves to the chain the name 
of Ptuwenzori, given to it by its first discoverer, Stanley, and 
adopted since then by the majority of geographers. 
Stanley had heard the natives dwelling to the 
north and west of these mountains call them by the 
names Ruwenzori, Ukonju, Bugombowa, Avuruka, Avirika, 
Ruwenzuru-ru, Ruwenjura, etc. He was of opinion that 
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