830 G. H. SQUIER 
probably exists a few feet below the surface. Above the ridge 
loess begins and covers all the upper part of the valley. It is 
seen in the bottom of the ravine asit skirts the ridge, some twenty 
feet below its crest. 
From the knob da concealed ridge extends toward the river 
terminating in the prominent point a. The front of the point is 
lined with very large masses of rock reaching up to six or seven 
tons in weight. Excavations show that the entire ridge is com- 
posed of like material. The largest masses are usually sandstone. 
Chert is abundant and all the local rocks are represented. Sand 
covers the ridge to a depth of two to three feet and fills the 
valleys on either side to an unknown depth. The general direc- 
tion of the ridge is shown by occasional protruding bowlders. 
As shown on the map, this ridge extends almost entirely across 
the course of the east valley. Yetits direction and other cir- 
cumstances seem to indicate that it belongs structurally to both 
valleys. 
About half a mile east of the two valleys just described 
occurs another, the largest in the Trempealeau bluffs. (It is 
the one in which the bed containing pebbles of extra local origin 
occurs. ) At its mouth, on the east side, a bowlder bed is 
superimposed on the edge of a sandstone plateau (sec. 3, Fig. 2). 
In the size and character of the material, in structure, etc., 
it is a ‘fairly representative example, although not as thick as 
most. No similar deposit is to be seen on the other side, 
although I should expect to find one under the sand. In the 
upper parts of this valley some interesting sections are furnished 
by washouts; owing, however, to their incompleteness they, for 
the most part, leave one in doubt as to the true nature of the 
structure displayed. 
In one place the point of a hill has been washed away, show- 
ing that at that point the hill consists of a bowlder bed of char- 
acteristic type, the material being piled nearly as steeply as it 
will lie. The top and sides are covered with loess. The entire 
junction is visible, showing that the transition is as abrupt as 
possible (sec. 4). It cannot be seen whether it is part of a 
