Glacial Lake Xicolct. — Upham. 113 
river with the Fox, which, by canal locks and dredging, has 
been made navigable to lake Winnebago for small freight 
boats and excursion steamers. 
The following series of altitudes, referred to the sea level, 
show the relation of the former lake Xicolet to the present 
lakes Michigan and Winnebago and to the Fox, Wisconsin, 
and Mississippi rivers. 
Lake Michigan, low and high stages. 578-584; mean stage. .581 
Upper limit of the red clay, deposited in lakes Chicago and 
Nicolet : 
Near Milwaukee, about 690 
30 miles northward, on the north line of Ozaukee county. 
about 780 
In Sheboygan county. 5 to 25 miles farther north 890-900 
A half mile west of the center of Memee township, in the 
south part of Manitowoc county 829 
At St. Xazian, also 829 
Near Chilton, east of lake Winnebago 953 
South of Stockbridge. near the middle of the east shore 
of this lake 971 
North of Stockbridge. a few miles from the last 939 
In section 6. Marshfield. Fond du Lac county 982 
In section 5. Taycheedah. near Fond du Lac 896 
Lake Winnebago 748 
Buffalo lake. Fox river 778 
Summit level of the canal 788-790 
Wisconsin river at Portage, feeding the canal, and separated 
from it by a guard lock, low and high stages 787-796 
Mississippi river at the mouth of the Wisconsin. 118 miles 
distant from Portage by the course of that river, low and 
high stages 604-626 
The alluvial deposit of the overflows from the Wisconsin 
river has filled. the old bed of the outlet of lake Nicolet to the 
depth of probably 10 feet or more at Portage and northward. 
The original channel bed, therefore, at the mouth of the 
glacial lake, has now an altitude, beneath the alluvium, 
of about 780 feet above the sea. It is thus 190 feet higher 
than the rock floor of the outlet from the glacial lake Chicago, 
about 150 miles distant to the southeast; and it is 20,0 feet 
lower than the swamp divide in the channel eroded at the head 
of the St. Croix river by the outflow from the glacial lake 
Duluth, about 22 j miles northwest of Portage. 
From my detailed examinations of the glacial lakes Souris, 
Agassiz, and Duluth. it seems to me quite certain that the red 
