128 G. F. WRIGHT LOESS IN NORTHERN CHINA AND CENTRAL ASIA 



feet above the sea, we ascended, along the line of the caravan route, to 

 the summit at Hanoor, from which point we struck off northward, fol- 

 lowing the edge of the plateau for a distance of 30 or 40 miles, where we 

 turned eastward, and after crossing two successive mountain ranges came 

 out at Shiwantse, and thence returned to Kalgan, and from thereby a 

 somewhat different route to Peking, making in all a journey of about 



Figure 1. — Route traveled 



Shaded portion indicates the approximate area in northeastern Asia supposed to have been 



recently submerged 



450 miles. The portion of it from Kalgan around the Mongolian border 

 to our starting point took us over a region where the glaciers, to account 

 for the loess of China, must have existed, if the loess were indeed of 

 glacial origin. The object of this paper can best be accomplished by a 

 somewhat detailed statement of the observations made on the most 

 typical localities in this part of our journey. 



But, as preliminary to this detailed statement, it will be profitable to 

 present in brief a few general facts bearing on the subject. 



Present Activity of erosive Agencies 



All the rivers of northern China are densely loaded with sediment de- 

 rived from the loess-covered areas through which they pass in the upper 

 portion of their courses. In this respect they much resemble the Mis- 

 souri. The vast plain of the Hoangho, in northeastern China, consists 

 essentially of this sediment, which has been deposited gradually by the 

 river. The river in the lower part of its course now occupies a channel 

 raised considerably above the great mass of the plain, which stretches 



