western shore, where our tent was pitched, was distinctly marked, in consequence of the impact of the waves, which work with the greatest force and reach their greatest height in precisely that direction. The escarpment of the shore is i to I I/2 m. high, and below it extends a gently sloping abraded terrace, in part overgrown with reeds. The water that washed it was at that time brownish grey and muddy.
At the very first glance it is patent to the simplest understanding that this lake must be a recent creation, and it can only be a very few years since its basin was filled with water. For its kamisch is extremely thin and poor; indeed, except for an occasional small scanty tuft, the shores are perfectly bare and barren. The shore, which consists of the same schor that occurs in several parts of the Desert of Lop, is brittle and friable when dry, but when moist forms the softest and most treacherous mud possible. The saliferous schor does not however in any way prove a hindrance to the sprouting of the kamisch; but here the water has made its appearance so recently that the kamisch has not had time to spring up. Whenever it accompanies the water, it desseminates itself very quickly. In fact, when I revisited the same spot a year later the kamisch had increased to such an extent that it was difficult to recognise it again.
The southern shore of our lake formed a pretty straight-edged terrace, sharp-cut, and perfectly sterile, and the jars and jardangs were arranged in two or more »storeys» of different heights. From a hill on the other side of this low clay ridge we observed yet another lake to the south, either connected with the Kara-koschun proper, or else forming a part of it. Along the southern shore there were at intervals patches of kamisch-stubble, surviving from some former overflow period, and presenting the same appearance as the kamisch-stubble in the interior of the Desert of Lop.
On our left we had two small elongated sheets of water; hence we directed our steps to the tongue of land which lay between them and the main lake. In these little lakes there is a sprinkling of tamarisk-mounds; while perfectly barren dunes of a pretty considerable size overlook their north-western shores. And there are dunes again on the tongue of land between the lakes themselves — a significant fact. They tell us that they were standing there already when the water first appeared upon the scene; otherwise the sand of which they are built up would never have been able to transport itself across the sheets of water that stretch to windward of them. On the other hand if no change takes place in the distribution of the water, these dunes will be able to maintain their present position a pretty long time, for the wind is moving them along the tongue of land out towards its extreme tip. Their horns or wings extend parallel to the shore; in other words, the same parallelism which governs all the relief forms throughout the Desert of Lop obtains also on this shore. The lakes extend from N. 6o° E. to S. 60° W. ; the groovings caused by wind-erosion stretch north-east and south-west; the steep sides of the dunes look towards the south-west; the prevailing winds and the storms come from the northeast; and it is the wind which both models the relief features and controls the dunes.
In places along the shore there is, as I have said, some dead wood; it is certainly old, for it is no longer standing on its own roots. Near to our camp rather large quantities of drift-wood were stacked up on the shore by the waves, though the pieces were all small and hard — another proof that - the lake is of recent origin. Owing to causes which we shall investigate lower down,
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