THE IOWAN- WISCONSIN BORDERS 
185 
Fig. 35. Map showing the moraine in part of Worth county. 
Work done in Worth county has revealed evidence which seems 
to warrant Mr. Williams’ contention for two distinct moraines 
or advances of the Wisconsin ice-edge. During the summer of 
1917, a large drainage ditch was in the process of construction. 
This ditch, where it cuts through the terminal moraine, sections 3, 
10, 14, and 23, Fertile township, was carefully examined in all 
parts of its course through the terminal moraine and many sections 
noted. The following section is quite typical of many others that 
might be given. ^ 
Feer Inches 
5. Black loamy soil 3 6 
4. Bluish gray clay, highly calcareous 10 
3. Sand, uniform in texture, rather fine, filled with small 
pelecypod shells 4-6 
2. Vegetable zone, filled with tree trunks, 1 inch to 3 inches 
in diameter 1 
1. Clay, compact, of bluish color Base 
It would seem that the animal and vegetable life, should they 
prove to be interglacial between the first and second advances of 
the Wisconsin ice, are criteria that may furnish some measure of 
the time interval between the two advances. 
After the first advance and retreat, enough time must have 
elapsed to permit vegetation to take hold on the surface and life 
to inhabit the marsh or lake areas. The sand represents probably 
the outwash from the ice-edge. 
