186 
IOWA ACADEMY OF SCIENCE Vor.. XXVII, 1920 
It seems highly possible that the drift marked as Wisconsin, 
located to the east of the outer moraine (see figure 35) is Wiscon- 
sin terminal moraine drift and represents the earliest advance 
of the Wisconsin ice-edge. It is between this drift and the junc- 
tion of the inner moraines of Williams that the above section 
was obtained. What is mapped as inner and outer moraine drift 
material by Williams may prove to be but local oscillations of the 
same advance, as the ice-edge was, no doubt, very lobate. 
De^partment op Geology, 
State Teachers College. 
