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 CHINA

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from the highlands of central Asia, which have determined the main watersheds. The general course of the rivers is thus from west to east, and whenever they meet these subordinate ranges they ultimately break across, though occasionally diverted for a time. Their course is thus sometimes a series of zigzags, now flowing parallel with the trend, and now breaking through at right angles, flowing in a deep rocky gorge. The formation of these

B. V. Darbishirc cr O.J.R.Howartn,

[geography

gorges—some of which on the upper angtse, and also on the west or Canton river, are 2000 feet in depth points to immense antiquity, and probably was preceded by a series of inland lakes. The extensive areas now filled with red sandstone such as exist in Hunan and Szechuen were doubtless the beds of such lakes. A specially characteristic feature of north China is the deposit termed loess, which not merely imparts to the

Engl.Miles

Oxford lyor

Sketch Map of China, showing Railway Concessions. country the physical character of the scenery, but also determines the agricultural products, the transport, and general economic life of the people. It is peculiar to north China, and is not found south of the Yangtse. The loess is a solid, but friable earth of brownish yellow colour,_ and when triturated with water is not unlike loam, but differs from the latter by its highly porous and tubular structure. Among its constituents, next to the argillaceous basis, fine sand and carbonate of lime predominate. It spreads alike over hills and valleys, smoothing over the irregularities, and has a depth, in many places, of over 1000 feet.

It is not stratified, and has a tendency to vertical cleavage. It is full of fossil land shells, and contains bones of quadrupeds, but has no remains of either marine or freshwater shells. From its porous nature water never lies on the surface. The rainfall is at once absorbed as_ by a sponge. On the other hand, moisture is retained in the lower portions for long periods. The drainage is consequently not carried on the top. Whatever streams or rivulets there are, at once cut their way through the friable earth to the subsoil, carrying down the debris to be deposited as alluvium on the plains. As the cleavage is