e 500 or 700
feet. The sandstone of the plateau has at first been hardened, then
quite metamorphosed into a chocolate-coloured schist. As at Chilole
hill, we have igneous rocks, apparently trap, capped with masses of
beautiful white dolomite. We still ascend in altitude as we go
westwards, and come upon long tracts of gneiss with hornblende. The
gneiss is often striated, all the striae looking one way--sometimes
north and south, and at other times east and west. These rocks look as
if a stratified rock had been nearly melted, and the strata fused
together by the heat. From these striated rocks have shot up great
rounded masses of granite or syenite, whose smooth sides and crowns
contain scarcely any trees, and are probably from 3000 to 4000 feet
above the sea. 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. It looks as if a sudden rent had been made, so as
to form the Lake, and tilt all these rocks nearly over. On the east
side of the lower part of the Lake we have two ranges of mountains,
evidently granitic: the nearer one covered with small trees and lower
than the other; the other jagged and bare, or of the granitic forms.
But in all this country no fossil-yielding rock was visible except the
grey sandstone referred to at the beginning of this note. The rocks
are chiefly the old crystalline forms.

One fine straight tall tree in the hollows seemed a species of fig:
its fruit was just forming, but it was too high for me to ascertain
its species. The natives don't eat the fruit, but they eat the large
gr