After walking about two miles we noticed a herd of hippopotami in a pool below a rapid. This was surrounded by rocks, except upon one side, where the rush of water had thrown up a bank of pebbles and sand. Our old Neptune did not condescend to bestow the slightest attention when I pointed out these animals; they were too wide awake; but he immediately quitted the river's bed, and we followed him quietly behind the fringe of bushes upon the border, from which we carefully examined the water. About half a mile below this spot, as we clambered over the intervening rocks through a gorge which formed a powerful rapid, I observed, in a small pool just below the rapid, the immense head of a hippopotamus close to a perpendicular rock that formed a wall to the river, about six feet above the surface. I pointed out the hippo to old Abou Do, who had not seen it. At once the gravity of the old Arab disappeared, and the energy of the hunter was exhibited as he motioned us to remain, while he ran nimbly behind the thick screen of bushes for about a hundred and fifty yards below the spot where the hippo was unconsciously basking, with his ugly head above the surface. Plunging into the rapid torrent, the veteran hunter was carried some distance down the stream; but, breasting the powerful current, he landed upon the rocks on the opposite side, and, retiring to some distance from the river, he quickly advanced toward the spot beneath which the hippopotamus was lying. I had a fine view of the scene, as I was lying concealed exactly opposite the hippo, who had disappeared beneath the water.