The westernmost of the Chinese provinces recently incorporated through Japanese influence under the name of Manchukuo furnishes a clear example of the control of geologic structure on the development of physiographic features, and of the dominant part played by the latter in the history of racial interaction and human settlement over many centuries.
Along the greater length of its Mongolian frontier China possesses a chain of natural barriers which have in the past restricted access from the north to a few well-known routes. The Ordos Desert and the arid strip north of the great bend of the Huangho connect with the basalt ramparts that mark the edge of the plateau as far east as Kalgan. Beyond this, the sector north of Peiping is protected by folded ranges which parallel the northwest trend of the coast. Only in Jehol does the strike of the structure offer a natural “gangplank” from . . .