Summary of Geological Observations. 
Valley. Moreover, the slopes of the strata are everywhere very steep, in places 
as mnc-h as and upwards of 60°. 
Ruwenzori must accordingly he regarded as resulting from an anticlinal or 
ellipsoidic upheaval, with a slope to the west on the west side, to the east on 
the east side, passing to the south on the south side, and probably to the north 
on the north side. 
The presence of this ellipsoidic upheaval, combined with the phenomenon 
of the great fractures above mentioned, and with the existence in the central 
parts of rocks resisting subaerial disintegration, would explain the origin of the 
Ruwenzori Range and of its lofty summits. 
Old Glaciation .—A phenomenon of great importance is the vast development 
of the glaciers of the Ruwenzori Range during the glacial period. 
The valleys of the Mobuku, the Bujuku, and the Mahoma were tilled by 
the glaciers which descended from the chief mountains. These uniting in a 
single ice-stream of great size, and filling up the Lower Mobuku Valley, must 
have easily extended as far as the plain of Ibanda. 
Proofs of this early glacial expansion are afforded by the numerous large 
erratic blocks; by the old moraines which occupy the Mobuku Valley from 
Bihunga to Kichuchu, and above which rises the Nakitawa Plain ; lastly, by the 
rolled and striated rocks which are so common on the higher parts of the 
mountain. Regarding the Nakitawa moraipe, it may be mentioned that the 
lake lying south-west of that district, and by the observers generally considered 
as volcanic, is, on the contrary, inter-morainic. 
Disregarding the erratic boulders which occur on the plain of Ibanda, and 
are not perhaps due to direct glacial transportation, the first undoubted proofs 
of old glaciation were met by me near the ascent of Bihunga, that is, at about 
4,500 feet, whereas at present the glaciers do not descend lower than about 
12,600 feet. 
On the western slope, too, the traces are evident of the passage of the old 
glaciers with scratched and rounded blocks and morainic formations. We were, 
however, unable to discover how far they had ranged on that side, as we did 
not advance very far in that direction. 
Recent Glaciation .—The Ruwenzori glaciers are referred to the so-called 
equatorial type ; that is to say, they form ice-caps which are at times of great 
thickness, and more or less completely cover the summits of the mountains. 
From these ice-caps branches ramify downwards and advance into the ravines, 
but seldom range, and then only a little way, beyond the lower level of 
the perennial snows, which here lies between 13,350 and 13,500 feet. 
The position of the glaciers once determined, the lateral moraines may be 
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