PHYSICAL GEOGRAPHY. 49 



grounds. In its upper part, its bed is upon sand, rolled peb- 

 bles, and sliingle (lO^aJIcts). 



" Like most of the rivers in this region, it has its sources 

 in lakes and swampy grounds, and has a tortuous and slug- 

 gish course till it reaches a greater declivity about 43° of 

 latitude, when it becomes much more rapid and direct, and 

 frequently pilches impetuously over rocky beds of carbo- 

 niferous limestone forming frequent bluffs on alternate sides. 

 This rock, which might furnisli an abundance of excellent 

 building materials, is overlaid in some places by deposits 

 of coal. Penned up, as it were, between the valleys of the 

 Missisippi and the Missouri, and those of their adjacent tribu- 

 tary streams, the Des Moines has no large tributary of its 

 own. Flowing through a wide and deep valley, the principal 

 waters which it receives are the drainings through deep and 

 long ravines, intersecting its shores, and rendering the travel 

 along them inconvenient and painful." 



I'he head streams of the Illinois span a large tract of coun- 

 try. The Kankake, its southern main constituent, rises in 

 a swampy ground south of Lake Michigan, and flowing 

 nearly westerly for more than 100 miles, unites with the Des 

 Plaines or Maple River, both of which names are transla- 

 tions of its Pottawatami appellation, Sheshikmaoshike, which, 

 from its size and the direction of its course, may dispute with 

 Kankake the title of principal constituent of the United 

 Stream, at a few rods below the point where Otokakenog 

 (uncovered breast), another primary branch, mingles with it, 

 coming from the northwest. This last stream has received 

 the name of Du Page, from a man who was buried on its 

 banks. 



When the tliree streams are united into one, it receives the 



name of Illinois : but it has still another primary branch 



coming from the northwest still further west, which enters 



4 



