The elevated plains among these mountain masses show great patches of ferruginous conglomerate, which, when broken, look like yellow haematite with madrepore holes in it: this has made the soil of a red colour.
On the watershed we have still the rounded granitic hills jutting above the plains (if such they may be called) which are all ups and downs, and furrowed with innumerable running rills, the sources of the Rovuma and Loendi.

The highest rock observed with mica schist was at an altitude of 3440 feet.

The same uneven country prevails as we proceed from the watershed about forty miles down to the Lake, and a great deal of quartz in small fragments renders travelling-very difficult.

Near the Lake, and along its eastern shore, we have mica schist and gneiss foliated, with a great deal of hornblende; but the most remarkable feature of it is that the rocks are all tilted on edge, or slightly inclined to the Lake.

The active agent in effecting this is not visible.