On the i 8th September we left the mouth of the Jagju-rapga and travelled up the magnificent and picturesque glen down which the river flows. According to our Tibetan escort, we should have found a far easier and shorter road had we kept farther to the north, and travelled by a glen the entrance to which we perceived to the north-west. But I was curious not only to find out where the river came from, but also to avoid coming into contact with Dutreuil de Rhins's route; accordingly we kept to its northern, that is its left, bank and proceeded west-southwest. At first we moved at some distance from the river, across a gently inclined plain, with a sprinkling of thin grass on it. We soon reached the eastern extremity of a not very big, but rather steep and fantastic, range, and then afterwards had this range immediately on our right. From the very extremity of the range a swelling proceeds towards the south-east, and it was at the eastern foot of this swelling that we found the seven old marginal terraces that I have already described. The river is not particularly winding, and along this section of its course it is free from waterfalls, the stream being very uniform in width. In an expansion of its glen the Jagju-rapga swells out into a little lake, which, to judge from its numerous sedimentary islands, must be shallow. One would hardly expect to find alluvial deposits such as these, for the river, when it enters the lake-like expansion, is as bright as crystal; but I have no doubt that after heavy rains considerable quantities of solid material are washed down from the mountains, and so find their way into the river, and eventually settle in the lake-like expansion. At its exit from the little lake the river makes a couple of sharp, deep-cut turns and in them its erosive power is considerable. This circumstance cooperates with the deposition of sediment to fill up the basin. On the northern shore of the lake, and at several meters above its surface, we observed a couple of distinct terraces, manifestly of fluviatile origin.
The slope of the mountain-range which runs south of the river is far less steep than that of the opposite range on the north; the cause of this is mainly the dip of the strata, which in the former is to the north-west. On the southern side
He din, yourney in Central Asia. IV. I I
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