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a more compact limestone of the same kind as that which is quarried in solid 

 blocks six miles farther down the river. The section is as follows in ascending : 



1. Fossiliferous, shaly, or flaggy Permian limestone, 6 feet. 



2. White soft clay, passing upward to reddish sand, 4 feet. 



3. Conglomerate and concretionary sandstone, 2 feet. 



4. Yellowish, coarse sandstone, 20 feet. 



5. Red, hard, ferruginous sandstone, with plants, 45 feet. 



The stratum No. 2, 4 feet thick, is the line of transition or of su- 

 perposition. In its lower part, and in contact with Permian limestone, it 

 is Permian. In its upper part, the reddish sand is Cretaceous. The hills 

 around are still higher by 20 to 40 feet, and all, from base to top, at least 

 from what is seen by exposures, are composed of the same hard red sand- 

 stone, which is more or less flaggy, and whose fragments are heaped in mounds 

 by the farmers and used for building or for wells. In all this country, with 

 the exception of clay-beds, which are irregularly distributed in regard to the 

 horizon of the strata, the whole compound of the group is sandstone, rarely 

 mixed in horizontal streaks with small pebbles, occasionally yellow and crum- 

 bling, but most generally hard, ferruginous, either compact or cavernous, like all 

 the ferruginous sandstones. Its appearance is so little varied that it is every- 

 where easily recognized without the evidence of its leaves. No formation 

 could show a more striking contrast than it does with that of the underlying 

 limestones of the Permian. In ascending upward through the higher strata 

 of the Dakota group, or in following the exposures of this formation along the 

 rivers to the west, the same uniformity is constantly remarked to the highest 

 point, where the upper beds of sandstone pass under the second or upper 

 group of the Cretaceous. For example, in Kansas, from the mouth of Salina 

 River to Fort Harker, I have all the time traveled along the banks of this red 

 sandstone. It is sometimes interstratified with beds of soft clay, Carbonaceous 

 matter, or streaks of coarse materials forming bands of conglomerate sandstone, 

 but the areas occupied by them are not of wide extent. They appear here 

 and there without apparent continuity, and are irregularly distributed in the 

 whole thickness. When near the surface, the clay-beds have been generally 

 decomjiosed and mostly destroyed under atmospheric action, forming hollows 

 or depressions, which in some localities mold the surface of the prairies into 

 groups of small domes or hillocks, like a miniature of what is seen in such a 

 grand scale in the Tertiary clay formations of the Mauvaises Terres. The 



