THE MISSISSIPPI VALLEY. 13 



But in the vicinity of the Falls the character of this river suddenly changes. 

 The profile here mounts up with a quick ascent, which renders idle all expec- 

 tation of stemming the current. The stream becomes, in fact, a succession of 

 rapids, falling through 362 feet in a space of 27tt miles, which is about twenty- 

 seven times as much as the Ohio falls in the corresponding portion of its course, 

 and more than the descent of Niagara river from Lake Erie to Lake Ontario, 

 which in the same space of about 27 miles passes over the Falls, and descends 

 through rapids almost as subhme as the cataract itself 



A further inspection of the profile of the Kanawha exhibits another fact some- 

 what remarkable in the descent of this great river. 



The acchvily of the Ohio, and that of its tributaries, increases continually as 

 we ascend towards their sources — forming, instead of a plane, a very uniform 

 curve in profile, presenting its concave surface upwards. But the outline of the 

 Great Kanawha, from the commencement of the rapids, where it assumes a new 

 character and the name of New river, is the reverse of this arrangement — the 

 slope of that remarkable stream becoming less and less abrupt the nearer we 

 approach its source, up to the very base of the Alleghany mountains, and its 

 profile presenting the form of a curve convex to the horizon. The scene of this 

 anomaly in the descent of great streams is at the passage of New river, through 

 the Gauley and other mountains, where stone clifls of unrivalled height and 

 beauty confine the torrent. 



The same pecuUarity is observed also, though in a less marked degree, in the 

 profile of the Greenbriar, a tributary of New river; but, with these exceptions, 

 all the great arms of the Ohio obey the law which prevails in the slope of their 

 common recipient, increasing in their acclivity from their mouths to their 

 sources, and often so regularly that the ordinates of increase might be closely 

 represented by an equation of httle complexity. 



Looking along the profile from east to west, we find the elevation of the 

 dividing ridge between the waters which flow into the Gulf of Mexico, and those 

 which reach the Atlantic through the lakes and the St. Lawrence, highest at 

 the sources of the Alleghany, in the State of New York, and falhng away as we 

 pass along the borders of the lakes towards the Mississippi. 



The height of the summit which divides the waters of the Genessee, flowing 

 into Lake Ontario, from those of the Alleghany, near the village of Friendship, 

 is 1678 feet above tide f further west, that which divides Bear lake, at the head 

 of the principal branch of the Connewango, from Lake Erie, is 1320 feet;* still 

 further west, the natural summit between Conneaut lake and the harbor of 

 Erie, in Pennsylvania, is 1095 feet; and proceeding further to the westward we 

 find the surface still more depressed, and the country assuming more and more 

 the appearance of a plane as its level descends. 



* Surveys of Charles Ellet, Jr- 



Art. 4. — 2 



