PECULIAR LOCAL DEPOSITS ON BLUFFS ADJACENT 
TO THE MISSISSIPPI. 
GEORGE HULL SQUIRE. 
The driftless area of Wisconsin includes three subdivisions 
•differing quite markedly in topographic peculiarities. They 
are: 
1. The lead region south of the Wisconsin. 
2. The hilly area between the Wisconsin and the Mississippi 
—the central. 
3. The region of low reliefs north of the northern escarp¬ 
ment of the Lower Magnesian Limestone—the northern. 
The distinctive characteristics of the third area are suffi¬ 
ciently obvious. 
The first two regions share in common a much stronger re¬ 
lief hut their distinctive differences are quite marked and of 
much importance in their bearing on local glaciation. 
I would refer more particularly to the somewhat greater 
altitude of the bluffs in the central region, the much greater 
depth and steepness of the valleys, and the greater depth of the 
fillings in the valleys. 
If we compare like parts of the two areas, the bluffs of the 
central one will show approximately two hundred feet the 
greater altitude. 1 
Its valleys, however, do not share in this greater elevation. 
On the contrary if we compare valley sections equally remote 
from the main divide their altitudes are not only relatively, 
but often actually less. They are consequently very much 
deeper. 
i There are very few altitude readings for the bluffs of the central 
area. The figures given were obtained indirectly. 
