Chapter XIV. The Yellala of the Congo.
At dawn (September 16), I began the short march leading to the Yellala.[FN#29] By stepping a few paces south of Nkulu, we had a fine view of the Borongwa ya Vivi, the lowest rapids, whose foaming slope contrasted well with the broad, smooth basin beyond. Palabala, the village of Nekorado on the other side of the stream, bore south (Mag.), still serving as a landmark; and in this direction the ridges were crowned with palm orchards and settlements. But the great Yellala was hidden by the hill- shoulder.
We at once fell into a descent of some 890 feet, which occupied an hour. The ground was red iron-clay, greasy and slippery; dew- dripping grass, twelve to fifteen feet tall, lined the path; the surface was studded with dark ant-hills of the mushroom shape; short sycomores appeared, and presently we came to rough gradients of stone, which severely tried the "jarrets." After an hour, we crossed at the trough-foot a brook of pure water, which, uniting with two others, turns to the north-east, and, tumbling over a little ledge, discharges itself into the main drain. An ascent then led over a rounded hill with level summit, and precipitous face all steps and drops of rock, some of them six and seven feet high, opposed to the stream. Another half hour, and a descent of 127 feet placed us under a stunted calabash, 100 feet above the water, and commanding a full view of the Yellala.
On the whole, the impression was favourable. Old Shimbah, the Linguister at Porto da Lenha, and other natives had assured me that the Cataracts were taller than the tallest trees. On the other hand, the plain and unadorned narrative of the "Expedition" had prepared me for a second-rate stream bubbling over a strong bed. The river here sweeps round from the north-west, and bends with a sharp elbow first to the south-west and then to the south- east, the length of the latter reach being between four and five miles. As far as the eye can see, the bed, which narrows from 900 to 400 and 500 yards, is broken by rocks and reefs. A gate at the upper end pours over its lintel a clear but dwarf fall, perhaps two feet high. The eastern staple rises at first sheer from the water's edge to the estimated altitude of a thousand feet, - this is the "Crocodile's Head" which we saw on the last march, and already the thin rains are robing its rocky surface with tender green. The strata are disposed at angles, varying from 35deg. to 45deg., and three streaks of bright trees denote Fiumaras about to be filled. Opposite it is the "Quoin Hill," bluff to the stream, and falling west with gradual incline. The noise of this higher fall can hardly be heard at Nkulu, except on the stillest nights.
Below the upper gate, the bed, now narrowing to 300 yards, shows the great Yellala; the waters, after breaking into waves for a mile and a half above, rush down an inclined plane of some thirty feet in 300 yards, spuming, colliding and throwing up foam, which looks dingy white against the dull yellow-brown of the less disturbed channel - the movement is that of waves dashing upon a pier. The bed is broken by the Zunga chya Malemba, which some pronounced Sanga chya Malemba, an oval islet in mid-stream, whose greater diameter is disposed along the axis of the bed. The north-western apex, raised about fifty feet above the present level of the waters, shows a little bay of pure sand, the detritus of its rocks, with a flood-mark fifteen feet high, whilst the opposite side bears a few wind-wrung trees. The materials are gneiss and schist, banded with quartz - Tuckey's great masses of slate. This is the "Terrapin" of the Nzadi. The eastern fork, about 150 yards broad, is a mountain-torrent, coursing unobstructed down its sandy trough, and, viewed from an eminence, the waters of the mid-channel appear convex, a shallow section of a cylinder, - it is a familiar shape well marked upon the St. Lawrence Rapids. The western half is traversed by a reef, connecting the islets with the right bank. During August, this branch was found almost dry; in mid-September, it was nearly full, and here the water breaks with the greatest violence. The right bank is subtended for some hundred yards by blocks of granite and greenstone, pitted with large basins and pot-holes, delicately rounded, turned as with a lathe by the turbid waters. The people declare that this greenstone contains copper, and Professor Smith found particles in his specimens. The Portuguese agents, to whom the natives carefully submit everything curious, doubt the fact, as well as all reports of gold; yet there is no reason why the latter should not be found.
The current whirls and winds through its tortuous channels, which are like castings of metal, in many distinct flows; some places are almost stagnant, suggesting passages for canoes. Here the fishermen have planted their weirs; some are wading in the pools, others are drying their nets upon the stony ledges. During the floods, however, this cheval-de-frise of boulders must all be under water, and probably impassable. Tuckey supposes that the inundation must produce a spectacle which justifies the high- flown description of the people. I should imagine the reverse to be the case; and Dr. Livingstone justly remarked[FN#30that, when the river was full, the Yellala rapids would become comparatively smooth, as he had found those of the Zambeze; and that therefore a voyage pittoresque up the Congo should be made at that season.