RESEARCH IN CHINA. PLATE XXIX. 

Twenty-five miles south of P’ing-yang-fu, Shan-si. View on ancient imperial highway showing the canyon developed in Huang-t’u 
by wear of traffic and wind. Two old levels of the road may be seen above the one in use, and the manner in which the 
long axles undercut the bluff may be noted; the endurance of the steep walls is indicated by depth of roadway. 
