; Geology and Mineralogy. 489 
meters above the sea-level, which is covered in great part with 
liss. The river Fénn-ho "(a stream flowing s onthward into the 
Hoang-ho, through the center of the Province of Shansi), occupies 
a deep channel cut through it along its western border. West of 
this — there is another mountainous region, in which flows 
north and south, for 300 miles, the Hoang-ho or epee River. 
Beyond, Jeeaagh the Provinces of Shensi and Kansu, the léss is 
widely spread; and, on the authority of the missionaries and the 
Chinese, it continues in the valleys to the most western sources of 
the affluents of the Hoang-ho, over 900 miles robes alte coast. The 
loss spreads northward along the plains or valleys into Mongolia, 
Southward, it occupies basins in the broad valley of the Wei, the 
largest tributary of the Hoang-ho; and it also occurs in the val- 
ley of the Han. It is found also farther east over parts of the low 
near Nanking, Tung-ting Lake, and Po-yang Lake, which are its 
lands of Honan and Shantung. South of Honan it exists in iso- 
€ ? 
otal to Baron von n Richthofen, 
The material of the = like that along the Rhine, is a brown- 
ish-yellow earth (whene the name “Yellow River,” given to the 
a very inded, exceedingly fine in grain, and friable 
when ; and affording on chemica ment, more or less car- 
bonate of lime. It often contains, at different levels, calcareous 
also p 
ing to the author, shells of fresh-water snails. Vegetable se 
also occur in it. From top to bottom it is penetrated by ve 
small tubular Swear d which are like shone — are now in many 
ever, at intervals usually of — than fifty feet (but vary ing from 
a few feet to more than a hundred), horizontal divisional ‘planes 
which are usually connected with planes of concretions. In con- 
sequence of these structural  aigicayh hie the léss fronts the val- 
leys with high vertical walls, in which are occasional horizontal 
terrace-like shelves. It becomes reduced by intersecting stream 
or streamlets, and the rills from the heavy rains, to regions = 
deep and narrow labyrinthine passage-ways, groups of oft ty o 
lisks, castles, clustered towers. Instructive views of its alate 
are cla in the volume. 
Baron von Richthofen discusses the theories as to the origin of 
the liss, sad adopts that which he had advocated in his memoirs 
