218 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



SANDUSKY RIVER. 



Sandusky River is a larger and more widely branching stream than any 

 of the tributaries of Lake Erie thus far discussed. It consists of a westerly 

 and a northerly flowing portion. The westerly flowing portion leads from 

 the escarpment of Eocarboniferous sandstone near (Jrestline westward down 

 th.e slope to the axis of the Scioto Basin. Instead of turning southward, as 

 the neighboring streams do, to enter the Scioto River, it turns northward 

 and flows down a gradual slope to Lake Erie. It enters Sandusky Bay at 

 the western end. The valley of this river is small, being only 20 to 60 feet 

 in depth and one-fourth mile or less in average width. It is in places cut 

 into rock a few feet, and appears to be largely independent of preglacial 

 drainage lines. 



MAUMEE RIVER. 



The Maumee River system has the greater jjortion of its drainage area 

 within the State of Ohio, but small portions are found in Indiana and Michi- 

 gan. The drainage of the two headwater forks of this system was formerly 

 southwestward from Fort Wayne to the Wabash. At that time Lake 

 Maumee occupied the district through which the Maumee flows, the mouth 

 of the old lake being near the point where the St. Marys and St. Joseph 

 rivers had their discharge. As this mouth stood higher than the portion of 

 the basin toward the east and the portion of the outlet toward the west, there 

 was a natural summit formed upon the withdrawal of the lake, from which 

 the waters of the St. Joseph and St. Marys rivers were free to flow either to 

 the east or to the west. By some accident of deposition or of slope the 

 stream found it easier to turn eastward than to maintain its original course 

 westward, and thus the Lake Erie drainage basin embraces these streams 

 as well as those which have been formed in the old lake bottom or were 

 tributary to the old lake. 



The Maumee River has a length of about 150 miles and a fall of 164 

 feet, the source being 735 feet and the mouth 573 feet above tide. It has 

 a shallow channel, perhaps 50 feet in average depth, excavated mainly in 

 the drift. It is not itself a navigable stream, but is followed closely by the 

 Wabash and Erie Canal, which for many years afl'orded a means of water 

 transportation. 



The St. Marys River has its source in Shelby County, Ohio, at an 



