THE PREGLACIAL DRAINAGE OF OHIO. 69 



is seen to flow between extensive bottom lands on which stand 

 the cities of Cincinnati, Newport and Covington. Here it re- 

 ceives the Licking from the south and Mill creek from the north; 

 the latter, like the Little Miami, coming through a valley in 

 which it seems almost lost as it meanders aimlessly back and 

 forth. Then the Ohio passes into a very diminished space at 

 Sedamsville, where it flows on rock bottom. This is the site of 

 another col (C); and from here the hills gradually recede to 

 North Bend. Three miles below North Bend was another col 

 (D) ; a little farther down the Ohio suddenly debouches into a 

 ver}' broad valley where it receives the Great Miami. Like the 

 two streams observed above here, the latter seems utterly incom- 

 petent to the excavation of the trough which it occupies. 



This valley holds its width to the mouth of the Kentucky, 

 varying somewhat from the average in different parts, as it 

 does elsewhere. One noticeable feature along this stretch is that 

 nearly all the tributary streams have a direction opposite the 

 current of the river; that is, in going down the main stream 

 one is looking toward the sources of those which flow into it. 

 There are also several abrupt bends ; in these the outer side of the 

 curve is at the foot of the steep hills or clififs, while on the other 

 side are wide bottom lands. At Sugar creek the river makes an 

 acute turn to the west, which course it holds past Carrolton, 

 where it receives the Kentucky. From this town it 'apidly 

 narrows until it reaches Madison (E). Here was the last col 

 above Louisville. The valley contracts until on the Indiana side 

 the water washes the solid rock, while on the Kentucky side 

 there is a strip of level land only wide enough to afiford room 

 for a single warehouse. 



Two miles below Madison, the river turns again toward the 

 south through a gorge which gradually expands until it opens 

 into the basin in which Louisville is situated. 



The interpretation of these facts is about as follows : 



When old Limestone was deflected northward by the col 

 at (B) it entered the depression lying north and east of Cincin- 

 nati. Here it received a considerable tributary from the east 

 by wav of the present East Fork. The united streams flowed 

 west, and reached Mill creek valley at the point (G) in the vicin- 



