118 Kansas Academy of Science. 



holes have been dug prospecting for silver in the boom days of the 

 place, hence the name "Silver City." 



Along east and south of Silver City ridges and mounds capped 

 with sandstone are noticed, the valley being some two miles wide. 

 In the tallest mound, two or three miles southeast, I found a thin 

 layer of lime — probably that has only a local occurrence, since I 

 failed to find it anywhere else. 



It seems that there are two important layers of sandstone in the 

 Lawrence shales from Silver City to the state line, and in the shale 

 separating them a thin stratum of very blue, hard limestone is 

 found which serves the purpose of easily locating the sandstone 

 layer; the upjjer stratum of sandstone forming the escarpment in 

 this formation; the under layer forming the many mounds in the 

 eastern part of the Lawrence shales. The blue limestone was seen 

 in many places, from two miles northeast of Yates Center to several 

 miles west and south of Elk City, and without doubt is permanent 

 within the boundary given. The extent north and south of these 

 limits is undetermined, but I suspect that this lime is continuous 

 in this position. A similar lime in the same position is found west 

 of Ottawa. 



The upper massive sandstone is from ten to thirty feet in thick- 

 ness, and beneath this is a clayey shale. This, being softer than 

 the sandstone above, is eroded faster, and therefore the escarpment 

 is usually very rugged, the sandstone outcropping in cliffs often 

 twenty to thirty feet in height, and in some instances more. Also, 

 in many places massive boulders have tumbled down from the sand- 

 stone, thus making this formation very picturesque and the scenery 

 very rugged and beautiful. This is especially noticeable where a 

 spring, which is very common in this formation, appears in the 

 soft clayey shale beneath the sandstone, or where a stream has eroded 

 away the softer material and the firmer sandstone has slipped down 

 the hillside as a great landslide or has gone down as massive boul- 

 ders. In some places the sandstone from the erosion of the shale 

 forms an overhanging wall, the so-called caves of this region. True 

 caves are found only in limestone formations. Many springs are 

 found flowing from the clayey shale beneath this massive sand- 

 stone. The water of these springs is of exceptional purity, as 

 shown by many analyses in volume VII, Geological Survey Re- 

 ports, and forms one of the attractive features of this section of 

 the state. The "Delaware Springs" is a noted example. Wells 

 dug in this region also furnish very excellent soft water. The ex- 

 planation is very simple. The coarse sandstone being nearly pure 



