Kirgis declared, it was only five days before that the river had assumed the dimensions of a spring-flood, a character which it would retain for yet two months longer. This unusual energy is therefore restricted to a relatively short period of the year. And although both before and after that season the river is not indeed altogether insignificant, yet in comparison its volume is but trifling. During the cold months it is frozen and its activity is then nil. When the flood is highest, which it would be about three weeks after our visit, it is said to rise a meter higher than it stood at then, and is indeed an immense flood, stopping the glen completely. That year the high water was said to have arrived earlier than usual, and that was considered to be a great gain for the seed-corn sown at Sandschu, where the fields were all ready waiting for the life-giving element. As a consequence of the unprecedented quantity of sediment and clay with which it was charged, the water was of precisely the same colour as the neighbouring mountains, so that the stream and the bottom of the glen were not very conspicuous features of the landscape. Indeed the river was only noticeable because it moved and had a broken surface. It had no white foam ; but where it did boil and froth, it still remained the same brownish-red as before. The sediment imparted to the river a strong odour, similar to that which emanates from the walls of a freshly plastered house. This sediment is also an eloquent witness: it consists partly of material brought down directly by the many thaw-water streams and partly also of fine material produced by the grinding together of the stones and gravel in the bed of the principal stream, and by the friction of the moving detritus against the bed of the river. In any case it is the result of disintegration and attrition, and is carried down out of the mountains to be deposited on the edge of the lowlands, where it serves to raise the scree at the northern foot of the mountains, on the border-line between the mountains and the lowlands of East Turkestan.
It was impossible to form anything approaching a trustworthy estimate of the volume without the help of a bridge, from which alone measurements could have been made. Next the right bank the velocity amounted to 1.25 m. in the second, but in the middle of the river it was a good deal more. Bearing in mind the severe friction against the stones and gravel in the bottom of the river, we may put the mean velocity at a meter in the second. The breadth was 24.6 m. and the mean depth fully 1.40 m. This last datum I obtained by measuring the mean depth on the following day, when the flood had subsided sufficiently, and then adding to it the height of the actual flood. On the basis of this calculation, the volume would therefore be 34.4 cub.m. in the second; it is however probable that the velocity in the middle of the river and throughout the greater part of the breadth was as a fact greater . than I m., so that we ought rather to put the volume at about 4o cub.m. in the second.
On the 5th May the Kirgis asserted, that there was no need whatever to be in a hurry; we should not be overtaken by the flood. On the contrary, it would be an advantage to wait, for the river would go on dropping all the morning; and indeed between 8 and 9 a.m., for instance, it did drop a good decimeter. Yet even when near its minimum, it made a fairly respectable stream, so much so that I was in some anxiety with regard to the more perishable part of my baggage. If a
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