CHAPTER XVIII. 



The Platte — Desert plains — Mirage — Arrival at the Rocky 



Mountains. 



The Platte, called by the Otoes Ne-braska, (Flat river, or 

 water,) is, as its name imports, almost uniformly broad and 

 shoal. It is fordable at almost any place, except when swol- 

 len by freshets, which occur in the Spring season, from the 

 melting of snow, and occasionally during the other portions 

 of the year, from excessive rain. Its bed is composed almost 

 exclusively of sand, forming innumerable bars, which are 

 continually changing their position, and moving downward, 

 till at length they are discharged into the Missouri, and 

 swept away to the ocean by that rapid and turbulent river. 



The range of the Platte, from extreme low to extreme 

 high water is very inconsiderable, manifestly not exceeding 

 six or eight feet. This is about the usual height of its banks 

 above the surface of the sand which forms its bed. The banks 

 are sometimes overflowed, but evidently to no great extent. 

 The rapidity of the current, and the great width of the bed 

 of the river, preclude the possibility of any extensive inun- 

 dation of the surrounding country. The bottom lands of the 

 river rise by an imperceptible ascent, on each side, extend- 

 ing laterally to a distance of from two to ten miles, where 

 they are terminated by low ranges of gravelly hills, running 

 parallel to the general direction of the river. Beyond these 

 the surface is an undulating plain, having an elevation of 

 from fifty to one hundred feet, and presenting the aspect of 

 hopeless and irreclaimable sterility. 



The Missouri in compliance with the usage of boat-men, 

 hunters, &c, has been usually considered under two divi- 



