464 ACROSS AFEICA. [Chap. 



To the west of Tanganyika a new geographical, ethnological, 

 zoological, entomological, and botanical region is entered. Close 

 to the lake the road leads over the southern spurs of the Ugo- 

 raa, the habitat of the mvuli, a tree very valuable to the na- 

 tives, as the large " dug-out " canoes which they use in naviga- 

 ting the Tanganyika are made of the trunk. 



The Kugumba tlows into the lake just to the west of the 

 south extremity of the Ugoma Mountains, through the northern 

 edge of the flat plain near the entrance into the Lukuga ; while 

 the Rubumba, which takes its rise close to the source of the 

 Rugumba, is found at a very short distance from the lake, flow- 

 ing away from it. The country is hilly, with occasional plains 

 until Ubudjwa is passed, when it becomes mountainous in char- 

 acter. 



Uhiya and Uvinza, the two next countries, are a series of 

 ridges running in different directions from the Bambarre 

 Mountains, which are the most important range in this part 

 of Africa. Beyond them is another lesser ridge divided from 

 them by a well-watered and fertile plain, and beyond this the 

 country is practically level, with the exception of a few rocky 

 hills, till the Lualaba is reached. 



The mountains and hills are, as usual, composed of granite, 

 gneiss, and quartz, with here and there a few patches of por- 

 phyry. 



The lower levels consist of strata of sand and water -worn 

 pebbles, and present the appearance of having been once the 

 bottom of some great sea. These beds of sand and pebbles 

 vary much in thickness and extent. 



Between the Bambarre Mountains and the Tanganyika a red 

 hematite ore is worked, but not in very large quantities. 



After the mountains are passed, the soil on the surface in the 

 plains is a rich red sandy loam, but in some of the water-courses 

 a dark -gray shaly sandstone. Round Manyara and its neigh- 

 boring villages this red soil is wanting; but whole hills are 

 composed of a black speculum ore. The iron obtained from it 

 being of excellent quality, accounts in great measure for the 

 goodness of the sniith's work. 



The country near the Lualaba is again composed of sand and 

 water-worn pebbles ; but the river is clearly working down the 



