A steam-boat here might surmount many difficulties, and give us the necessary corrections for a map, which cannot be effected by sailing with a constant wind, owing to the often diametrically opposite windings, and the endless difficult calculations. In order to bring such a steam-vessel safe over the upper cataracts of Wadi Halfa, or even of Es-Suan, it must be constructed in such a manner that the paddle-wheels could be entirely taken out, so that it might be towed over by ropes, or it must be built in Khartùm, which, indeed, might be difficult from want of good timber, as the sunt-tree, though very strong, affords but brittle wood. The greatest difficulty would be the establishment and protection of coal-magazines; and with regard to applying charcoal to this purpose, although the White Stream in its lower course has forests enough, yet not so on its middle and upper part: and even if the requisite wood should be found, much time must be lost in felling and preparing it for charcoal. A considerable number of men also would be always necessary for the protection of these establishments, and their consumption of victuals would be so great, that their provisions would leave no room for the charcoal, as the vessels could not be _heavier_ laden. There is another very great consideration,—these labyrinths go through the marshy regions. If only a few men, therefore, should be embarked, and other vessels employed to take up coals, their crews must consist entirely of men selected for the purpose, and known to one another, in order that they might communicate with the inhabitants of the shore, and be able to aim at something more than simply ascertaining the course of the river. Europeans only are fit for this, as they have ideas of humanity, and subjection to the will of One. At last we have determined to take the clumsy kaiàss in tow, at the droll request of Hässeïn Aga. Our vessel began with it, in order to form a line with the other larger Dahabiës. At eleven o’clock we discerned, upon a marsh island, near the left shore, some thirty talle-trees; this genus we had missed for some time. Here we turn S.S.E., and with a small bend E.S.E., and then E. by S. We were driven by the east wind close to the right bank of the reeds before we had reefed the sails. The only remaining hope that the river may follow its winding course, and bring us, with the assistance of rowing a short way, into a more favourable direction.