GRIMSLEY. | Geography and Topography. 37 
state, and this is the most important center for the production 
of plasterin Kansas. Five companies, with six mills of modern 
construction, are engaged in this work, which centers in the 
towns of Hope, Dillon, Solomon City, and, formerly, Gypsum 
City. 
TOPOGRAPHY OF SOUTHERN OR MEDICINE LODGE ARBFA. 
The southern area is situated 120 miles southwest of Gypsum 
City. Plate lV. The northern part is drained by the Medicine 
Lodge river, which rises in Kiowa county and flows southeast 
to Medicine Lodge, where it turns abruptly south, flowing into 
Oklahoma, and there it empties into the Salt Fork of the Arkan- 
sas river. The southern part drains into the Nescatunga river, 
flowing southeast through Comanche and Barber counties into. 
Oklahoma, where it also joins the Salt Fork. The main branch 
north of the Medicine Lodge river is Elm creek, which has a 
channel parallel to the river, flowing south of east, and turning 
south following the course of the river. The creeks south of 
the river, Bear, Dog, Little Bear, Bitter, Cedar, Walnut, flow 
northeast in parallel channels. This uniformity in direction is 
a striking feature. 
The divide between the two larger rivers is broad in Comanche 
county, with an elevation of 2200 feet just east of Coldwater, 
but it rapidly narrows to the southeast, in Barber county, where 
its elevation is 1900 feet, descending to 1600 feet in the valley 
of the Medicine Lodge river, within a distance of seven miles. 
Plate V gives a view of the river valley and Gypsum Hilis in the 
distance. This divide trends parallel with the river and turns 
south near the central part of Barber county, still parallel with 
the river. 
This area, as was stated under the geological section, consists 
of soft red shales covered by a heavy gypsum layer, as shown 
in Plates Vito X. The gypsum rock is soft, but much firmer 
than the friable shales below. The old plateau surface is at a 
much higher level than even the highest portion of the central 
area. All the conditions, therefore, have been favorable for 
rapid erosion, and the streams have cut deep valleys, separated 
