The accustomed shape in which the raw material is used as a medium of exchange is in spear heads[22] or in spades. Throughout the whole district of the Upper Nile these answer all the purpose of our current coin. Although the superficial veins of iron ore, for hundreds of miles, do not differ much in their appearance, there are only certain localities which produce an ore that, under the primitive mode of smelting, yields a remunerative supply of genuine metal. One of these prolific veins is found in the proximity of Kurshook Ali’s Seriba. With a perseverance for which I could not have given them credit, the natives have dug out trenches some ten feet deep, from which they have obtained a material very like our roe-stone. Considerable quantities of red ochre are discovered, but they are not turned to any account, through ignorance of a proper way of manipulation. Just before the commencement of seed-time, in March, the Dyoor make a general move away from their huts, partly for the purpose of dragging the rivers for fish, and partly to busy themselves with iron-smelting in the woods. In the shaded centre of a very wooded spot they construct their furnaces of common clay, making them in groups, sometimes as many as a dozen, according to the number of the party. Their wives and children accompany them, and carry all their movables. In the midst of the wilderness, otherwise so desolate, they form a singular picture. The stems of the trees gleam again with their lances and harpoons; on the branches hang the stout bows ready for the buffalo hunt; everywhere are seen the draw-nets, hand-nets, snares and creels, and other fishing-tackle. There is a mingled collection of household effects, consisting of gourd-shells, baskets, dried fish and crocodile, game, horns, and hides. On the ground lie piles of coals, of ore, of cinders, and of dross. Petherick, the first explorer of this Dyoor district, has given a very accurate account of their primitive method of smelting iron, so that I may be repeating in a degree what has been related before: many things, however, there are which appeared to me under a somewhat different aspect. [Sidenote: DYOOR SMELTING FURNACE.] [Illustration: Dyoor Smelting-furnace.]