The valleys of denudation enclosed by these hill ranges guide the streams towards Liemba or the four rivers which flow into it.

The country gradually becomes lower, warmer, and tsetse and mosquitoes appear; so at last we come to the remarkable cup-shaped cavity in which Liemba reposes.

Several streams fall down the nearly perpendicular cliffs, and form beautiful cascades.

The lines of denudation are continued, one range rising behind another as far as the eye can reach to the north and east of Liemba, and probably the slope continues away down to Tanganyika.

The watershed extends westwards to beyond Casembe, and the Luapula, or Chambeze, rises in the same parallels of latitude as does the Lofu and the Lonzna.
The Arabs inform me that between this and the sea, about 200 miles distant, lies the country of the Wasango--called: Usango--a fair people, like Portuguese, and very friendly to strangers.