232 RESEARCH IN CHINA. 
the contours of the valleys, which, if the explanation be correct, should 
exhibit the older valley features warped above the canyon on the section 
cd and above the sharply cut portion of the abandoned valley bd; and 
these same old valley features should sink to the level of the upper valleys 
northwest of the point c on the main river, and west of the point 6 on 
the southwest fork. 
The upper valley of the Sha-ho above the curious point of diversion— 
that is, from Li-ytian-p’u to the divide—is characterized by the features 
of a stream which has grown through the development of its headwater 
gullies on a steep slope. Its drainage area is narrowly limited by a moun- 
tain rim, which bends around it everywhere, at a nearly equal distance 
from the main channel. The tributaries are all of approximately the 
same length, and spread like the twigs at the end of a branch of a deciduous 
tree. They gash the mountain slopes into hundreds of ravines, and are 
growing vigorously at their extremities as they energetically sink their 
deep channels. The valley is a beautiful example of the headwaters of 
an autogenous stream, which, developing upon a steep slope, is rapidly 
extending the area of its watershed. 
If we look for evidences of stages of development in the history of 
this upper valley, they are meager, because the growth has been rapid 
and without prolonged interruptions, but they are not altogether wanting. 
The latest incident is expressed in the relatively wide and flat valley floor 
above Li-yiian-p’u, which has already been interpreted as an effect of 
local warping. Evidence of similar widening, which probably was of 
greater extent and longer duration, is found in the flats on the mountain 
spurs, representing an old valley floor about 1,800 feet, 530 meters, above 
the present channel, above Lung-ts’tian-kuan. The present elevation of 
these spurs is not far from 4,400 feet, 1,340 meters; that is, but little 
below the crest of the pass, 4,800 feet, 1,350 meters, and practically the 
same as the altitude of the valley of the Ts’ing-shui-ho, just across the 
range. It is probable that this old valley stage corresponds with that 
which is marked 6 in the sketch, Plate XXX, representing the view 
looking northwest from the divide above Lung-ts’tian-kuan. If so, the 
features now lie several hundred feet lower on the eastern side of the 
divide. 
The characteristics of the upper Sha-ho are, without exception, those 
of a stream developing on a steep slope. ‘The process of development is 
still progressing, and the river has immediately before it the diversion 
of the Ts’ing-shui-ho and upper T’ai-shan-ho, which will probably take 
place through the lowest pass, that above Lung-ts’tian-kuan, and result 
in an inversion of the Ts’ing-shui-ho above Shi-tsui. 
