Twenty miles below Narukus the Nosop separates from the Oup, and continues more to the east, which has already been described. Forty miles to the west of the junction of the Oup and Kuruman rivers is a large vlei, thirty-two miles in length, called Hogskin vlei, and in places from two to three miles broad. This vlei receives three small rivers, the Knaas, Snake, and Moi; their fountain-heads are in the hill district on the west, covered with bush and rugged in form. The country is very pretty and picturesque, with fine kameel-doorn trees, prickly thorns, and mimosa trees. On the east of this large vlei is an extensive salt-pan, but not used, as there are no inhabitants except Bushmen and Korannas. To the south is the Back river, which rises in those beautiful mountains known as the Brinus hills; from the topmost springs it flows in two directions, one to the Great Fish river, the other eastward past Liefdote, Tobas, and Klopper vlei, turns south-east, and enters the Hygap sixty miles above the Orange river, and seventeen miles below Swaart-Modder, where I built a stone house under the hanging cliff, in the dry bed of the Hygap. The other two rivers that complete this ancient river system are the Molapo or Mafeking, and the Kuruman. The former rises on the central watershed in the district of Molapo in Montsioa's territory. The eye of this river is situated 26 degrees 7 minutes South latitude, 26 degrees 20 minutes East longitude, in a lovely wooded glen, 5350 feet above sea-level, and only ten miles from the main eye of the Molmane river that falls into the Limpopo basin; the watershed passing across the desert divides the two. From this fountain the Molapo turns westerly, passing Melemas and Macebe's kraals, continuing in the same direction for 315 miles, joins the Nosop above described, and forms the main stream of which the Hygap is a continuation. The Setlakooly and Moretsane are the only branches of any size that drain the country in that long distance. The Kuruman river rises south of the mission station of that name, flows west and enters the Hygap a few miles below the junction of the Oup, passing through a wild and broken country the last ninety miles of its course. The Hygap river from this point to the Orange is a broad and deep river, and from the lofty and perpendicular sandstone rocks, reaching in many places 200 feet in height at the bends, where the current acted upon them in its course down, it is evident that at a remote period it was a river of some magnitude; the force of water in many places has undermined the base of the cliffs, forming caves, that have been used by the early inhabitants as dwelling-places, and in one of which I erected a stone front to live in for a time when in that region many years ago.