J7 j THE IMPROVEMENT OF RIVERS. 



River with its tributaries, Rough and Barren Rivers, has seven locks with fixed dams. 

 The Wabash River, the largest northern tributary, has one lock with a fixed d.im, 

 while on the Tennessee and Cumberland Rivers, the largest southern tributaries, other 

 locks are under construction. 



\Vhen a project for the entire river has been completed it will comprise a system 

 from Pittsburg to Cairo, over a thousand miles on the main artery alone; and with a 

 valley as rich as that of the Ohio, the resulting development of commerce will be 

 enormous. 



With the exception of this river and its tributaries, there are at present few mov- 

 able dams projected or under construction, the most noteworthy exception being that 

 of the drum dam on the Osage River. 



