THE MISSISSIPPI VALLEY. 35 



same reservoirs, having been replenished by the preceding flood, would, how- 

 ever, have brought it up again to 6 feet or more. In November and December 

 the natural flow of the river required no aid. 



No less than ten times in the course of the year 1846 the navigation could 

 have been maintained at a height, generally of 6, and never less than 5 feet, 

 by means of three reservoirs of moderate size, of which the total cost could not 

 exceed that of twelve or fifteen miles of ordinary railroad. 



The same object may be accomplished with equal certainty, and probably 

 for an outlay not materially greater, without the necessity of placing any dams 

 across the principal tributaries of the Ohio. The smaller branches, nearer to the 

 mountains, abound in eligible sites for reservoirs, where an ample store of water 

 may be accumulated in numerous lakes of inconsiderable dimensions, and where 

 no land need be submerged, nor other valuable property damaged by the 

 works. There are some important advantages to be gained by selecting these 

 remote sites for retaining at least a part of the store. The smaller streams not 

 being navigable, no costly locks will be required to accommodate the trade ; 

 while the construction of the dams will be rendered exceedingly cheap by the 

 abundance of excellent materials, and the firm foundations which the rocky 

 valleys affbi'd. The reservoirs that will there be formed will be surrounded by 

 precipitous cliffs, and quite secluded from all public and private interests. In 

 such positions the mass of water may be retained, while the great streams need 

 not be resorted to at all ; or if used, used only as the sites of capacious regu- 

 lating reservoirs^ corresponding in their functions with the distributing basins of 

 common water-works. 



