THE WILD CAMEL - OVER THE ASTIN-TAGH. 307
December 25th. The minor watercourses which we crossed over to the east of our camp run out of the Astin-tagh towards the south, breaking by a small transverse glen through the westernmost part of the southern parallel chain. This chain is in the quarter mentioned rather ragged, consisting of several small detached portions. After surmounting a low threshold or saddle in the latitudinal valley (alt. 2918 m.), we perceived to the south a more energetically excavated transverse glen, by which the main drainage channel of the western part of the valley issues. Through this gap or gateway we obtained our last glimpse of the plains of Tsajdam. After that the southern chain of the Astin-tagh forms a connected and continuous crest. From it and from the chain on the north of this latitudinal valley countless tiny brooks flow down into the main watercourse up which we were then travelling. This channel, which is of considerable size, is bordered by rounded marginal terraces two meters high.
Still following the ancient road, we crossed diagonally over the latitudinal valley and so approached the northern chain of the Astin-tagh, after we had adopted a more northerly and finally a north-north-westerly course, crossing on the way over a secondary threshold between two minor free-standing sections of the mountains. And we crossed over yet another similar threshold amongst these scattered groups of heights. From these the eroded watercourses gather from different directions into the main channel of the latitudinal valley. The upper part of this last originates at a minor swelling in the valley itself. The offshoots of the chain closed in more and more. Then, turning our backs upon the latitudinal valley, we began to ascend a transverse glen leading up to a pass at the summit of the northern chain. The pass proved easy of access and had an altitude of 3247 m. The only part that was at all steep was the upper part of the northern declivity. The descending glen runs at first to the north-west, then towards the north-east, and soon issues into a fresh latitudinal valley. To the N. 6o° E. we saw distinctly yet two other parallel chains belonging to the system of the Astin-tagh. Hence this system, which we previously found to embrace two parallel chains — I call them the Upper and the Lower Astin-tagh — consist here, where they form the north-east border of the basin of Tsajdam, of not less than four chains, all parallel to each other and running from south-west to north-east. The two middle chains, which are the largest, answer without doubt to the Upper and Lower Astin-tagh, while the chain that comes farthest south may be regarded as a shorter subsidiary range, and so too may the one farthest north. We shall lower down come across the prolongation of this last. The latitudinal valley in which we were marching towards the N. 62° E. is thus the orographical continuation of the latitudinal valley that we traversed diagonally between Basch-kurghan and Basch-jol. Both the Upper and the Lower Astin-tagh, between which we at this time were, give the impression of being relatively low chains, an effect attributable in no slight degree to the considerable altitude of the latitudinal valley itself. This valley is several kilometers broad, and at the points where we first struck it, its bottom was composed of large expanses of barren reddish clay, an indication that it was a small self-contained drainage basin, in which the rain-torrents off the adjacent mountains are wont to gather. On the right we had a distinctly outlined escarpment, gapped by a number of eroded water-
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