GLACIAL LAKES 331 



by the glacier : Lake Duluth in the Superior basin, Lake Chicago 

 in the Michigan basin, and Lake Maumee in the Huron-Erie 

 basin (Fig. 360). 



We may now, with profit, trace the successive episodes of the 

 glacial lake history, considering for the earlier stages those changes 

 which occurred within the Huron-Erie basin, since, these are in 

 essential respects like those of the Michigan and Superior basins, 

 although worked out in greater detail. Lake Chicago must, 

 however, be brought into consideration, since in all save the earli- 

 est and the later stages, the waters from the Huron-Erie depression 

 were discharged through the Grand River into this lake and 

 thence by the so-called " Chicago outlet " into the Mississippi 

 (plate 20 A). 



The early Lake Maumee. The area, outline, and outlet of 

 this lake are indicated upon Fig. 360. Its ancient beaches have 

 been traced, as well as the water-laid moraine beneath its former 

 ice cliff; and no observant traveler who should take his way 

 down the ancient outlet from Fort Wayne, Indiana, past the town 

 of Huntington, could fail to be impressed by its size, suggesting 

 as it does the great volume of water which must once have flowed 

 along it. Now a channel a mile or more in width, its bed for the 

 twenty-five miles between Fort Wayne and Huntington may be 

 seen from the tracks of the Wabash Railway as a series of swamps 

 merely, while at Huntington the Wabash river enters by a young 

 V-shaped valley at the side, much as the Mississippi emerges into 

 the old channel of the Warren River at Fort Snelling,. Minnesota 

 (seep. 327). 



The Huron River of southern Michigan, which now discharges 

 into Lake Erie, then found its lower course blocked by the glacier 

 and was thus compelled to find a southerly directed channel now 

 easily followed to the northern horn of the crescent of Lake 

 Maumee. 



The later Lake Maumee. When the ice lobe had retired its 

 front sufficiently, an outlet lower than that at Fort Wayne was 

 uncovered past the city of Imlay, Michigan, into the -Grand 

 River, and thence through Lake Chicago and its outlet into the 

 Mississippi. This old outlet south of Chicago follows the course 

 of the present Drainage Canal and the line of the Chicago & 

 Alton Railway. The traveler journeying southward by train from 



