Arising early next morning, I was assured that it is necessary to cross the stream in order to reach the Cataracts. Tuckey did so, but further inquiry convinced me that it is a mistake to march along the northern bank. Of course, in skirting the southern side, we should not have approached so near the stream, where bluffs and débris rendered travelling hopeless. The amiable ichthyophagi agreed for two fathoms of fancy cloth to ferry us across the river, which is here half a mile broad. The six-knot current compels canoes to run up the left shore by means of its backwater, and, when crossing, to make allowance for the drift downwards. The aneroid now showed 860 feet of absolute altitude, and about sixty-five feet above the landing-place of Banza Nokki; the distance along the stream is fourteen miles, and thus the fall will be about five feet per mile below the Borongwa ya Vivi. We could see from a level the "smaller rapids of Vivi" bursting through their black gate with angry foam, flashing white from side to side. No canoe could shoot this "Cachoeira," but I do not think that a Nile Dahabiyah or a Brazilian Ajôjô would find great difficulty. Between us and the rapids, the concavity of the southern bank forms a bight or bay. The vortices, in which Tuckey's sloop was whirled round despite oars and sails, and in whose hollow the punt entirely disappeared, "so that the depression must have been three or four feet deep," were nowhere seen at this fuller season. The aspect of the surface is that of every large deep stream with broken bottom; the water boils up in ever widening domes, as though a system of fountains sprang from below. Each centre is apparently higher than its circle; it spreads as if a rock had been thrown into it, and the outer rim throws off little eddies and whirls no larger than a thimble. The mirrory surface of the lower river thus becomes mottled with light and shade, and the reflected image of the trough-cliff is broken into the most fantastic shapes.