286 The American Geologist. May, 1900 
About a third of a mile farther west, beyond the hollow of 
Brownie lake, Superior avenue again cuts into a massive hill, 
the excavation on its highest southern side being about 600 
feet long and 30 feet high. Section 3 of plate VI I shows gray 
till here 4 to 20 feet deep, underlain to the base of the cutting 
by sand and gravel. All the surface is formed of till, and its 
depth is greatest in the central part of the excavation. The 
lower limit of the till is clearly defined, there being no inter- 
stratification with the modified drift. During the final melting 
of the ice, its streams, probably flowing down from the surface 
through a crevasse or moulin, deposited the modified drift, and 
this became enveloped by till. The conditions were apparent- 
ly in some degree analogous with the formation of certain 
drumlins in Madison, Wis., and elsewhere, which contain 
modified drift as a nucleus, covered by till.* 
These sections lie directly in the line that would be the 
western continuation of the Lowry hill esker series. That 
gravel and sand deposit terminates north of Cedar lake b\ 
abutting against a marginal moraine which includes the hills 
cut by Superior avenue and thence extends northward past 
Keegan and Sweeney lakes, with numerous massive and high 
hills, 900 to 975 feet above the sea. 
On Western aveiiue. Three-fourths of a mile north- 
northeast from the sections noted on Superior avenue, some- 
what similar sections were observed on Western avenue, 
which likewise runs from east to west. Section 4 of plate 
VII is the cut made by this avenue close west of the inter- 
section of Russell avenue. It was observed on the higher 
south side of the cut, and is reversed in drawing to corre- 
spond with sections i and 2. The length is about 400 feet, 
and the hight 25 feet. Red till forms all the upper part, to a 
maximum depth of nearly 20 feet, having the obscurely lamin- 
ated or foliated structure before noted, although it is an indis- 
criminate mixture of clay, sand, gravel and boulders, a typical 
till. Near the center of the section, it includes a shred of yel- 
low till, a foot thick and six feet long. In the lower part of 
the section, along all its length, the red till is underlain by a 
layer of yellow till, 2 to 6 feet thick, partly contorted, bounded 
*Am. Geologist, vol. xiv. pp. 69 83, with maps and sections, Aug., 
1894. 
