HAWORTH. | Physiography of Western Kansas. A5 
“reached the soft, saliferous shales, and consequently have narrow 
“valleys. : 
“But while this was going on, the Arkansas river was slowly 
“working its way northward by wearing away the soft Dakota sand- 
“stones and shales along its northern bank. As the course of the 
“river to this point was northeast and the course of the creek to 
“the southeast, their valleys finally met. A long, wedge-shaped 
“ridge remains, which separates the upper courses of their valleys. 
“The breaking down of so much sandstone necessarily left be- 
“hind great quantities of sand. In the great quantity of sand lying 
“to the south of this wedge-shaped mass of land and in frequent 
“southerly winds, we have the conditions requisite for producing the 
“present basin. The sand blown by the wind across the mouth of 
“this valley formed a drift back of the point of this wedge between 
“the valleys. The drift gradually increased in length and hight 
“until it became a barrier entirely across the valley of the small 
“creek and formed a great basin. The drifting of snow often pro- 
“duces similar results, though on a smaller scale. Could the stream 
“have had considerable water flowing in it continually, it might have 
“been able to keep its channel clear; but probably there was not 
“water enough or current strong enough to carry away the sand 
“that drifted into the channel. 
“Nearly all the wells that have been sunk in this basin produce 
“very strongly mineralized water, much of it so strong that cattle 
“will not drink it. The water is commonly spoken of as salty, 
“but no analysis of the water has yet been made. The mineralized 
“condition of the water is doubtless due to two causes, the evapora- 
‘tion of so much water over the surface and the leaving behind of 
“mineral constituents in the wearing away of the saliferous shales.” 
THE UPLANDS. 
The general physiographic features of the uplands of Kansas 
have already been hinted at while discussing the different streams. 
Throughout the greater part of the whole western half of the state 
there is an approach to a level peneplain condition covering the 
whole of the territory. This is particularly true over the Tertiary 
areas of the west. The dip of the strata of the Cretaceous lime- 
