GEOGRAPHY OF USAGARA. 231 



gravel ; their stony walls, overrun with vegetation, 

 tower high on either hand, and the excess of inclination 

 produces after heavy rains torrents like avalanches, 

 which cut their way deep into the lower plains. During 

 the dry season, water is drawn from pits sunk from a 

 few inches to 20 feet in the re-entering angles of the 

 beds. Fed by the percolations of the soil, they unite 

 the purity of springs with the abundance of rain-sup- 

 plies, — a comfort fully appreciated by down-caravans 

 after the frequent tirikeza, or droughty afternoon- 

 marches in the western regions. 



The versant of the mountains varies. In the sea- 

 ward and the central sections streams flow eastward, 

 and swell the Kingani and other rivers. The southern 

 hills discharge their waters south and south-west through 

 the Maroro River, and various smaller tributaries, into the 

 " Rwaha," which is the proper name for the upper course 

 of the Ruhji. In the lateral plains between the ridges, 

 and in the hill-girt basins, stagnant pools, which even 

 during the Masika, or rainy season, inundate, but will 

 not flow, repose upon beds of porous black earth, and 

 engendering, by their profuse herbage of reeds and 

 rush-like grass, with the luxuriant crops produced by 

 artificial irrigation, a malarious atmosphere, cause a 

 degradation in the people. 



The climate of Usagara is cold and damp. It has 

 two distinct varieties, the upper regions being salu- 

 brious, as the lower are unwholesome. In the sub- 

 ranges heavy exhalations are emitted by the decayed 

 vegetation, the nights are raw, the mornings chilly and 

 misty, and the days are bright and hot. In the higher 

 levels, near the sources of the Mukondokwa River, the 

 climate suggests the idea of the Mahabaleshwar and the 

 Neilgherry Hills in Western India. Compared with 



Q 4 



