GEOLOGICAL PAPERS. 121 



above it nearly 200 feet, surrounded by a great white coping of gypsum from 

 twelve to fifteen feet thick. The wall runs southward for several miles, with 

 some openings, and terminates abruptly by a turn directly west. Northward its 

 termination is a bold promontory, and the neck, with gypsum absent from it in 

 places, is only wide enough on the top for one person to walk. From this point 

 the wall retreats, forming a deep amphitheater, with isolated buttes, and towers, 

 and caps, and all up the western valley towers, pinnacles and buttresses are re- 

 peated, advancing toward or retreating from the river. When approached, the 

 lights and shadows on the gypsum have the appearance of quaint gables and 

 mansard roofs. (Hay, 8th Bien. Rep. Kan. St. Bd. Agri., vol. XIII, pt. II, pp. 

 106, 107.) 



The portion of the state which is inohided in the Smoky Hills up- 

 land division is the north-central part. It is so named from the 

 Smoky hills, in Saline county, w^hich have also given their name to 

 the Smoky Hill river. The formations found in the upland are the 

 Upper Cretaceous rocks. The area may be referred to as denuded, 

 considered with reference to the country to the west, which is covered 

 with the Tertiary formations. It is not improbable that the Tertiary 

 beds, which form a constructional plain in the western portion of the 

 state, since the close of the period of their deposition, have been re- 

 moved by erosion from a large portion of the area of the Smoky Hills 

 upland. The topographic features are largely of indistinct-terrace 

 and broken-escp^pment type, with occasional lone hills or mounds. 

 Along the southeastern border there are a number of places at which 

 the more resistant sandstone horizons of the Dakota have given rise 

 to features such as Pawnee rock, in Barton county ; Smoky Hill 

 buttes and Soldier Cap mound, in Saline county ; and the Pulpit 

 rocks, resen>bling perched glacial boulders, at Rock City, Ottawa 

 county. Similar hills and groups of mounds occur in Lincoln, Ells- 

 worth and Russell counties, being there also formed by Dakota sand- 

 stones. The upland is traversed by a large number of streams flowing 

 eastward in nearly jjarallel channels and having moderate valleys 

 The divides between them have a general uniformity of broken slopes 

 and gentle terraces. The rocks which constitute them outcrop prin- 

 cipally along the streams as bluffs, and in places form the walls of 

 canons. The area of the Benton formation is more regular in its 

 topographic features than the Dakota, since it consists of interstrati- 

 fied limestones and shales of a quite uniformly varied character. To- 

 ward the western border of the upland the Fort Hays limestone and 

 Niobrara chalk (which succeeds it) are the protecting element in what 

 is known as the Blue Hills escarpment. The Blue hills proper arc 

 generally considered as occurring in Russell county and extending to 

 the north and south for some distance. The same general feature ex- 

 tends along the entire line of outcrop of the formations, and the name 

 is here extended to the escarpment produced by them. The softer 



