Rocky Mountains, , 381 



yet known, but the fact that there is such a range, is partially 

 substantiated by the concurrent testimony of the traders and 

 hunters of the Missouri, with whom it is a noted land-mark, 

 and is more fully corroborated by the hydrography of the 

 country, as may be shown by the map. 



The third is a range of hilly and broken country, commenc- 

 ing on the Wisconsan, near the Portage, and extending north- 

 wardly to Lake Superior. To this range we have taken the 

 liberty to give the name of the Wisconsan hills. The Ocooch 

 and Smoky mountains before mentioned, are connected with 

 this range. In 'its geological characters, and more especially 

 in its metallic productions, so far as our inquiry will enable 

 us to decide, it appears nearly allied to the Ozark moun- 

 tains, and circumstances are not wanting to induce the opi- 

 nion that they were once the same continuous range. Dr. 

 James is decidedly of the opinion, that the metalliferous re- 

 gion of the Mississippi, which extends from Red river, to 

 Lake Superior, in the direction of these two ranges, strongly 

 indicates that a continuous range, as just hinted, once had 

 an existence. 



The Mississippi river may be regarded as occupying the 

 lowest part of the valley, from its great estuary, the gulf of 

 Mexico, to its confluence with the Missouri and Illinois. 

 Thence to Lake Michigan, the immediate valley of the Illi- 

 nois, is to be viewed as the lowest part of the great valley 

 under consideration. This conclusion necessarily results from 

 an attentive consideration of the characters of the three rivers 

 just mentioned. If the inclinations of the plains down which 

 these rivers respectively flow, be in any degree proportionable 

 to the velocities of their currents, the plain of the Illinois will 

 be found to have far the least inclination, inasmuch as the 

 velocity of its current is not more than one-fourth of that of 

 either of the others. But in order to have a more distinct 

 view of the matter, let us assume the parallel of latitude in- 

 tersecting the Illinois at its head, or point of confluence of 

 the Kankakee and Des Plains rivers, and suppose a vertical 

 section cut in the direction of the parallel. Such a section 

 would intersect the Missouri at the distance of nearly seven 

 hundred miles from its mouth, the Mississippi at about two 

 hundred and sixty, and the Illinois at two hundred and fifty 

 from the same point. Hence allowing that the plains of each 

 have the same inclination, the point of intersection on the 

 Missouri, would be at a greater elevation than that on the 

 Mississippi, and that on the Illinois would be less elevated 



