178 MY FIRST JOURNEY IN NORTH-EASTERN TIBET.
right angles just west of the lake. On the other hand his account of the grouping of the mountain-ranges is inaccurate. Let us take first the mountains on the north side of the basin of the Atschik-köl; there Roborovskij has entered on his map no less than seven parallel ranges, all stretching from the north-west to the south-east. The highest lies farthest to the north-east, namely the »Ajajalik-tagh», which is represented on the map as being covered with fields of perpetual snow, crowning the crest to which my peak A3 belongs. The chain farthest to the south-west is quite short, and rises on the right bank of the Arka-taghning-su. On the right bank of the Ullugh-su there is a meridional range, and from its eastern side five of the seven chains proceed. From the point of view of orography and erosive action this arrangement is absurd as well as inconceivable; besides, the traveller did not see all these ranges, and consequently ought not to have entered them on his map. West of the Ullugh-su he shows the range of Musluk running east and west. Now there cannot be the slightest doubt that the »Ajajalik-tagh» is the eastward continuation of this same Musluk, so that instead of the seven ranges mentioned we have only one culminating range, which stretches from west to east until it dies away in the region north-east of the lake, a range that lies parallel to the Arka-tagh and a host of other ranges in northern Tibet. Possibly, like the Arka-tagh, it may have one or more subsidiary chains of foot-hills; but any way it must be regarded as a distinct and separate range, quite as much as the Arka-tagh is.
The range that bounds the basin of the Atschik-köl on the north is cut at right angles by the deep transverse glen of the Ullugh-su or upper Tschertschendarja. By following this glen upwards Roborovskij escaped crossing the range by a pass, though I crossed it by a pass between B3 and C3. In consequence of this he did not enjoy such an excellent opportunity as I did to study the broad features of the orographical structure.
Thus we find the same faults in Roborovskij's map of the country south of the Atschik-köl that we have already noted in his map of the Arka-tagh in the region around Schapka Monomacha. He depicts the former as a very straight and regular main range throughout; such does exist of course, and it is not in that that the errors complained of are to be discerned. But he shows fully a dozen spurs and offshoots jutting out from this range towards the west-north-west, and gives a length of not less than 170 km. to the longest of them, which rests its western extremity upon the river and thence sinks clown to the Atschik-köl. It is these spurs and offshoots that appear so very absurd. In reality they have no connection with the Arka-tagh, for its northern offshoots are short and meridional, while the ranges to the north of them run east and west and are in several places pierced by the streams of the Arka-tagh, these last terminating, some in the valley of the Atschik-köl, others in the basin of the Kum-köl. Apart from these orographical mistakes Roborovskij's reconnaissance of this region is especially instructive and valuable.
October 7th. We now travelled away from the snow-clad spur west and north-west of Camp LXVII. There was a gap in it, which appeared to promise a pass, possibly a water-divide between some of the tributaries of the Tschertschendarja and the Toghri-saj, which we were now approaching. At first we bore to the east, travelling across rounded ridges of débris, bordered by deeply trenched
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