Summaiy of Geological Observations. 



Valley. Moreover, the slopes of the strata ai-e everywhere very steep, in places 

 as niiuh as and upwards of GO". 



Kuwonzori nnist accordingly be I'egarded 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, p.assing to the south on the south side, and probably to the north 

 on the north side. 



The presence of this ellipsoidic upheaval, coml)ined 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- 

 Kuwenzori Kange and of its lofty summits. 



Ohi lUnciatkm. — A phenomenon of great importance is the vast development 

 of the glaciers of the Kuwenzori Kange during the glacial period. 



The valleys of the JNIobuku, the Bujuku, and the Mahoma were filled 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 ; l)y the old moraines which occupy the JMobuku Valley from 

 Rihunga to Kichuchu, and aliove which rises the Nakitawa Plain ; lastly, by the 

 rolled and sti'iated rocks which are so common on the higher parts of the 

 mountain. Regarding the Nakitawa moraine, it may be mentioned that the 

 lake lying south-west of that district, and liy 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 undoul)ted 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 moraiuic formations. We were, 

 however, una1)lL' to discovei' how far they had ranged on that side, as we did 

 not advance very far in that direction. 



liecent Glaciatiun. — The Kuwenzori glaciers are referred to the so-called 

 equaforial 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 blanches ramify downwards and advance into the ravines, 

 but seldom range, and then oidy a little way, beyond the lower level of 

 the })ereiniial snows, which here lies between 13,350 and 13,500 feet. 



The position of the glaciers once detei'uiiried, the latei'al moraines may be 



391 



