a man, evidently of a superior mind, who left his own countrymen, the Barotse, and came down the river, took advantage of the falls, and led out a portion of the water there for irrigation.  Such minds must have arisen from time to time in these regions, as well as in our own country, but, ignorant of the use of letters, they have left no memorial behind them.  We dug out some of an inferior kind of potato (’Sisinyane’) from his garden, for when once planted it never dies out.  This root is bitter and waxy, though it is cultivated.  It was not in flower, so I can not say whether it is a solanaceous plant or not.  One never expects to find a grave nor a stone of remembrance set up in Africa; the very rocks are illiterate, they contain so few fossils.  Those here are of reddish variegated, hardened sandstone, with madrepore holes in it.  This, and broad horizontal strata of trap, sometimes a hundred miles in extent, and each layer having an inch or so of black silicious matter on it, as if it had floated there while in a state of fusion, form a great part of the bottom of the central valley.  These rocks, in the southern part of the country especially, are often covered with twelve or fifteen feet of soft calcareous tufa.  At Bombwe we have the same trap, with radiated zeolite, probably mesotype, and it again appears at the confluence of the Chobe, farther down.

As we passed up the river, the different villages of Banyeti turned out to present Sekeletu with food and skins, as their tribute.  One large village is placed at Gonye, the inhabitants of which are required to assist the Makololo to carry their canoes past the falls.  The tsetse here lighted on us even in the middle of the stream.  This we crossed repeatedly, in order to make short cuts at bends of the river.  The course is, however, remarkably straight among the rocks; and here the river is shallow, on account of the great breadth of surface which it covers.  When we came to about 16d 16’ S. latitude, the high wooded banks seemed to leave the river, and no more tsetse appeared.  Viewed from the flat, reedy basin in which the river then flowed, the banks seemed prolonged into ridges, of the same wooded character, two or three hundred feet high, and stretched away to the N.N.E. and N.N.W. until they were twenty or thirty miles apart.  The intervening space, nearly one hundred miles in length, with the Leeambye winding gently near the middle, is the true Barotse valley.  It bears a close resemblance to the valley of the Nile, and is inundated annually, not by rains, but by the Leeambye, exactly as Lower Egypt is flooded by the Nile.  The villages of the Barotse are built on mounds, some of which are said to have been raised artificially by Santuru, a former chief of the Barotse, and during the inundation the whole valley assumes the appearance of a large lake, with the villages on the mounds like islands, just as occurs in Egypt with the villages of the Egyptians.  Some portion of the waters of inundation comes from