190 



GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



MISSISSINAWA KIVER. 



Mississinawa River, a southeastern tributary entering the Wabash 

 near Peru, has a length of about 100 miles. Its source is in western Ohio, 

 10 or 12 miles beyond the State line, on the north slope of the elevated 

 limestone district which occupies eastern Indiana and western Ohio. At its 

 source the altitude is probably 1,100 feet above tide. In the 25 miles from 

 its source to Ridge ville, Ind., the stream has a fall of about 5.5 feet per mile, 

 descending with the plain which it follows on the south border of the 

 Mississinawa moraine, and cutting but 15 to 30 feet into the plain. From 

 Ridgeville to Marion, a distance of 50 miles, the rate of fall is but little 

 more than 3 feet per mile. The stream in this distance has deepened its 

 channel slightly, but at Marion is scarcely 50 feet below the bordering 

 plain. Most of the work accomplished by the stream is in the section 

 between Marion and the mouth, a distance of only 30 miles. Its fall in this 

 section is about 5.5 feet per mile, or fully as great as in the headwaters. 

 The depth of the channel increases from about 50 feet at Marion to fully 

 100 feet in the vicinity of its mouth. It is excavated mainly in drift, but at 

 some points has extended a few feet into the underlying rock strata. 



EEL RIVER. 



Eel River, a northeastern tributary of the Wabash, entering at Logans- 

 port, has a length of about 85 miles. Its source is on the inner border of 

 the great Erie-Saginaw interlobate moraine, a few miles north of Fort 

 Wayne, at an elevation of about 850 feet above tide. The average fall of 

 the stream is very nearly 3 feet per mile, the elevation of the mouth being 

 543 feet. The following table of distances and elevations is based upon 

 Williams's list of altitudes, given in the Tenth report of the Indiana 



geological survey: 



Altitudes along Eel Iiivei\ 



Altitude 

 (above tide). 



Source, about 



Columbia City 



Collamar 



Liberty Mills 



North Manchester 



Eel River railroad bridge, in Miami County 

 Mouth, at Logansport 



85 

 70 

 58 

 50 

 45 

 30 

 



850 

 816 



750 

 721 



