THE WATERSHED BETWEEN TWO DRAINAGE AREAS. 45
probable that it flows along the foot of the southern mountains and joins the main brook somewhere near Camp XII.
Just east of the transverse valley there is a meridional threshold or saddle in the latitudinal valley. Beyond it another threshold became visible to the east. The ground here is sandy with some grass, and sometimes small blocks of igneous rock, probably granite, were seen. A second, smaller valley from the north had a little brook in the branches turning westwards. The ground rises slowly and is soft, with fine gravel on the surface, A third valley from the north had a perfectly dry bed filled with fine gravel and with an erosion terrace on its right side at least 4 m. high, proving that a rather energetic erosion had been acting here in bygone times. Only at some distance up in the valley a left erosion terrace was also to be seen. Protected by it there still was a stripe of fresh snow. From the mountains to the left, flat protuberances or simply screes are projecting southwards across the latitudinal valley; at each one of them one hopes it is the boundary of the Aksai-chin Basin, but every time there appears a new little threshold to the east. Three more little brooks come from the north. As far as we have been able to see, nearly all the water of the main brook comes from transverse valleys through the northern mountains. This is quite natural, for the northern mountains are mightier and higher than the southern and, therefore, catch more of the humidity brought by the monsoon. Still at so late a season as now, or the middle of September, the northern ranges are, on their southern slopes, more exposed to the sun, whereas the southern mountains are more in the shade. Already at the end of October these brooks will, no doubt, be frozen to the bottom.
The pink range to the south which from Camp XIV had appeared in a foreshortened perspective, during the course of the day's march unfolded its splendid panorama in all its details, its rugged ridges and wild peaks, its irregular snow-fields and its steep, rocky slopes in reddish yellow and pink colours of brilliant effect. On account of the fresh snow it was impossible to tell whether any rudimentary glaciers were formed. This fascinating range quite dominates the landscape by way of its unusually bright colours and its picturesque relief. At intervals the rising ground concealed the range. But as we finally reached the last transverse threshold at 5,273 m., it opened out in all its splendor. And north of it extended the intensely
blue lake, which had been discovered by Wellby in 1896. Some 12 or 13 km. west of the lake was also the point where we entered Wellby's and Malcolm's route, which we followed for only I o km., as they turned S. E. and marched along the southern shore, while my caravan marched on the northern shore, and I myself crossed the lake by boat.
This transverse threshold is important as it divides the drainage area of the Lake of Aksai-chin from the well-defined and comparatively small basin of Lake
IIIFカラー高解像度
