GEOLOGICAL PAPERS. 119 



ing the course of the Arkansas river within the state. This stream, 

 after making a peculiar bend, parallels approximately the western 

 border of the upland into Oklahoma, where it finds its way around 

 the south end. The streams of the northern part of the state have 

 likewise adjusted themselves to the structure of the rocks on the 

 western border of the upland, and joined their volumes in maintain- 

 ing the valley of the Kansas river across it. In determining the 

 disposition of the drainage from the Great plains, the Flint hills 

 upland likewise determined the former distribution of the Tertiary 

 formations by deflecting the streams carrying the sediments, or re- 

 tarding the velocities of those eroding their channels across its resist- 

 ant beds and causing them to drop their loads. The eastern margins 

 of the Tertiary formations have been largely removed. Judging from 

 their present extent and relations, as well as the distribution of 

 materials derived from them, we may safely assume that they did not 

 transgress eastward in Kansas farther than the boundary of the Flint 

 Hills upland. The following description of the Flint hills, which 

 present the most pronounced characteristics of the upland, is prin- 

 cipally from observations along the railway, extending from Moline 

 to Winfield, crossing their most broken portion : 



The Flint hills extend in a general north and south direction, and occupy ap- 

 proximately the southern part of Chase county, the western borders of Greenwood, 

 Elk and Chautauqua counties, and the eastern portions of Butler and Cowley. 

 Fall, Elk and Big Caney rivers, which are tributaries of the Verdigris, have their 

 sources in the many small streams cutting the eastern escarpment of the Flint 

 hills. The streams on the western slope (structural plain) are tributaries of the 

 Walnut. The Cottonwood, a tributary of the Neosho, sweeps in a broad curve 

 to the north, around the head waters of the two drainages above mentioned. 

 . . . The divide between these several streams, with its uneven configura- 

 tion, is known as the Flint hills. . . . The general position of the ridge may 

 be located on a map by the significant names of the towns — Flint Ridge, Sum- 

 mit, Beaumont, and Grand Summit. In their southern portion, where crossed 

 by this section, the valley of Grouse creek, which extends from north to south, 

 divides them into two ridges, the eastern of which is known as the Big Flint 

 hills, and the western as the Little Flint hills. ... To the north of the 

 Flint hills, as here defined, the same geological formations are exposed in the 

 valley of the Kansas river and its tributaries, and give rise to the terraced bluffs 

 which are characteristic of the country around Junction City and Manhattan. 

 . . . The Flint hills derive their name from the large amount of flint which 

 is found over their surface. Nearly all the limestones composing them contain 

 some flint, and a few of them carry heavy beds of it. The weathering away of 

 the limestones has left the enclosed masses of flint, which are strewn over the 

 surface in such profusion as to seriously interfere with travel. . . . The Flint 

 hills owe their contour wholly to erosion, there being no evidence whatever of 

 marked disturbances of the strata, which occupy nearly horizontal positions 

 [with a low dip to the westward]. They are characterized by even terraces and 

 small canons and gulches. Along the top of the terraces, which are covered 



