But a more luxuriant valley, from three to four miles broad, begins further on, rich in herbage, and full of ethel-trees, all crowning the tops of small mounds. Here we encamped near a pond of dirty rain-water, frequented by great flocks of doves and water-fowl, and a well called Ízayen, in order to wait for Utaeti. The well was only about three feet deep, but the water brackish and disagreeable. Our friend came at length, and it was then decided to march during the night, in order to reach the Kél-owí; we therefore left our pleasant camping-ground about half-past nine in the evening, favoured by splendid moonlight. So interesting was the scene, that, absorbed in my thoughts, I got considerably in advance of the caravan, and, not observing a small path which turned off on the right, I followed the larger one till I became conscious of my solitary situation, and, dismounting, lay down in order to await my companions. Our caravan, however, had taken the other path, and my fellow-travellers grew rather anxious about me; but my camel, which was evidently aware of the caravan ahead of us, would not give up this direction, which proved to be the right one, and after I had joined the caravan we were obliged to return to my former path. Here we found the small Kél-owí caravan encamped in the midst of a valley well-covered with herbage, near the well Karáda. Our new companions were perfect specimens of the mixed Berber and Sudán blood, and, notwithstanding all their faults, most useful as guides. It was two hours after midnight when we arrived; and after a short repose we started again tolerably early the next morning. For the first hour we kept along the valley, when we began to ascend a narrow path winding round the slope of a steep promontory of the plateau. The ruins of a castle at the bottom of the valley formed an object of attraction. The ascent took us almost an hour, when the defile opened to a sort of plateau with higher ground and cones to the left. After another ascent four miles further on, over a rocky slope about 180 ft. high and covered with sand, we encamped at an early hour, as the heat was beginning to be felt, in a valley with sidr-trees and grass, called Erázar-n-Ákeru. A large basin of water, formed by the rains in a small rocky lateral glen joining the large valley on the west side, afforded a delightful resting-place to the weary traveller. The basin, in which the negro slaves of our Kél-owí swam about with immense delight, was about 200 ft. long and 120 ft. broad, and very deep, having been hollowed out in the rocks by the violent floods descending occasionally from the heights above. But on a terrace about 200 ft. higher up the cliffs, I discovered another basin of not more than about half the diameter of the former, but likewise of great depth. All along the rocky slope between these two basins, cascades are formed during heavy rains, which must render this a delightfully refreshing spot. [Sidenote: Sunday, July 28th.]