CHAPTER IV.
Geology and description of the Waiyau land. Leaves Mataka's. The Nyumbo plant. Native iron-foundry. Blacksmiths. Makes for the Lake Nyassa. Delight at seeing the Lake once more. The Manganja or Nyassa tribe. Arab slave crossing. Unable to procure passage across. The Kungu fly. Fear of the English amongst slavers. Lake shore. Blue ink. Chitané changes colour. The Nsaka fish. Makalaosé drinks beer. The Sanjika fish. London antiquities. Lake rivers. Mukaté's. Lake Pamalombé. Mponda's. A slave gang. Wikatani discovers his relatives and remains.
28th July, 1866.—We proposed to start to-day, but Mataka said that he was not ready yet: the flour had to be ground, and he had given us no meat. He had sent plenty of cooked food almost every day. He asked if we would slaughter the ox he would give here, or take it on; we preferred to kill it at once. He came on the 28th with a good lot of flour for us, and men to guide us to Nyassa, telling us that this was Moembé, and his district extended all the way to the Lake: he would not send us to Loséwa, as that place had lately been plundered and burned.
In general the chiefs have shown an anxiety to promote our safety. The country is a mass of mountains. On leaving Mataka's we ascended considerably, and about the end of the first day's march, near Magola's village, the barometer showed our greatest altitude, about 3400 feet above the sea. There were villages of these mountaineers everywhere, for the most part of 100 houses or more each. The springs were made the most use of that they knew; the damp spots drained, and the water given a free channel for use in irrigation further down: most of these springs showed the presence of iron by the oxide oozing out. A great many patches of peas are seen in full bearing and flower. The trees are small, except in the hollows: there is plenty of grass and flowers near streams and on the heights. The mountain-tops may rise 2000 or 3000 feet above their flanks, along which we wind, going perpetually up and down the steep ridges of which the country is but a succession.
Looking at the geology of the district, the plateaux on each side of the Rovuma are masses of grey sandstone, capped with masses of ferruginous conglomerate; apparently an aqueous deposit. When we ascend the Rovuma about sixty miles, a great many pieces and blocks of silicified wood appear on the surface of the soil at the bottom of the slope up the plateaux. This in Africa is a sure indication of the presence of coal beneath, but it was not observed cropping out; the plateaux are cut up in various directions by wadys well supplied with grass and trees on deep and somewhat sandy soil: but at the confluence of the Loendi highlands they appear in the far distance. In the sands of the Loendi pieces of coal are quite common.[16]
Before reaching the confluence of the Rovuma and Loendi, or say about ninety miles from the sea, the plateau is succeeded by a more level country, having detached granitic masses shooting up some 500 or 700 feet. The sandstone of the plateau has at first been hardened, then quite metamorphosed into a chocolate-coloured schist. As at Chilolé 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 grubs which come out of it. The leaves were fifteen inches long by five broad: they call it Unguengo.
29th July, 1866.—At Magola's village. Although we are now rid of the sepoys, we cannot yet congratulate ourselves on being rid of the lazy habits of lying down in the path which they introduced. A strong scud comes up from the south bringing much moisture with it: it blows so hard above, this may be a storm on the coast. Temperature in mornings 55°.
30th July, 1866.—A short march brought us to Pezimba's village, which consists of 200 houses and huts. It is placed very nicely on a knoll between two burns, which, as usual, are made use of for irrigating peas in winter time. The headman said that if we left now we had a good piece of jungle before us, and would sleep twice in it before reaching Mbanga. We therefore remained. An Arab party, hearing of our approach, took a circuitous route among the mountains to avoid coming in contact with us. In travelling to Pezimba's we had commenced our western descent to the Lake, for we were now lower than Magola's by 300 feet. We crossed many rivulets and the Lochesi, a good-sized stream. The watershed parts some streams for Loendi and some for Rovuma. There is now a decided scantiness of trees. Many of the hill-tops are covered with grass or another plant; there is pleasure now in seeing them bare. Ferns, rhododendrons, and a foliaged tree, which looks in the distance like silver-fir, are met with.