430 THE ILLINOIS GLACIAL LOBE. 



The beach appears on the west side of the Chicago River, in sec. 19, 

 T. 41, R. 13 E., about a mile northwest from the terminus of the bar. From 

 this point southward to < >ak Park the shore is usually a cut bank ranging 

 from 6 to 25 feet in height, with occasional deposits of beach gravel and 

 sand along its front. At Oak Park there is an extension of gravel down 

 the east side of the Des Plaines River similar to that of the bar east of the 

 Chicago River noted above. A ridge or bar 20 to 40 rods in width and 10 

 feet or more in height extends from Oak P.a-k south about 2 miles to the 

 south part of sees. 13 and 14, T. 39, R. 12 E.. and there terminates abruptly 

 with a level nearly 20 feet above the plain on its immediate borders. 



Passing to the west side, of the Des Plaines River, the beach appears 

 about a mile above the southern end of the bar just described, and passes 

 in a curving* course westward through the south edge of Maywood, in sees. 

 14, 22, and 16, T. 39, R. 12 E. This portion of the beach is only 2 to 4 

 feet in height, and at the west it fades out completely. Its faintness in this 

 district is probably due, in part at least, to the protection from wave action 

 occasioned by the bar just described. Upon passing south and crossing 

 Salt Creek, about a mile from the point where the beach fades out, it 

 reappears as a well-defined ridge, composed of sand and gravel, rising from 

 10 to 12 feet above the border of the plain on the east, and having a 

 breadth of 30 to 40 rods. Following this beach southward, it changes in 

 about a mile to a cut bank, which is well defined from that point southward 

 to the lake outlet, a short distance south of Lagrange. Its course is 

 through the east part of the city of Lagrange, where it is in the form of a 

 cut bank 10 to 15 feet in height. 



Passing to the west side of the outlet, near Willow Springs, the shore 

 line is found as a, cut bank along the east face of the prominent morainic 

 tract which occupies the interval between the two outlets of the lake. 

 Though mainly a cut bank, the beach is represented occasionally by 

 deposits of gravel and sand. 



South from the southern or Sag outlet, the shore is carved on the 

 inner face of the Valparaiso moraine with banks 5 to 20 feet or more in 

 height, but with only occasional deposits of gravel and sand. Upon 

 approaching the State line, however, near Glenwood, the shore bears away 

 from the moraine, and deposits of gravel and sand are built up to a heiglit 

 of 6 to 12 feet or more. These are sometimes in the form of a single ridge, 



