TWENTY-SEVENTH ANNUAL MEETING. 255 



the county is trenched, by the Delaware and its tributaries, deep into the lime- 

 stones. In some respects, this valley is much like that of the Big Stranger in 

 Leavenworth county. The loess is over most of the county, and gives the 

 rounded forms and smooth slopes to the topography of the central plateau; 

 and there is scarcely any outcrop of the bedrock from near the Missouri bluffs 

 to the valley of the Delaware. 



GEOLOGY. 

 The bedrock of this county is of the coal measures. The connection of par- 

 ticular strata with those of the neighboring counties has not been worked out; 

 but it would seem that some of the coal measures limestones might be traced 

 through from Leavenworth county. At the mouth of Whiskey creek, a mile 

 south of the city of Atchison, this section overlooks the valley: 



Clay, slope. 



a. Dimension limestone 18 in. to 2 ft. 



b. A whitish brick shale 4 to 6 ft. 



c. A quarried limestone, somewhat irregular l»j to 20 ft. 



d. Black shale 4 ft. 



e. Dimension rock 2 ft. 



f . Another quarried rock below 2 ft. 



There is here a resemblance to the Leavenworth city section; but if the 

 two dimension rocks are the same, it would indicate the absence of the whole 

 series of sandstones and sandy shales of the Wyandotte-Leavenworth plateau. 

 It is more likely that (a) represents one of the limestone ledges below the pla- 

 teau that are not there of the "dimension" character; and that the sandy 

 shales are hidden above under the loess. A mile further south this outcrop 

 occurs also near the Missouri river: 



Slope. 



Quarried limestone 10 ft. 



Shale ■. 10 to 20 ft. 



Rock (limestone) 10 ft. 



Clay shaie .... 15 ft. 



Coal 1 ft. 6 in. 



Black shale 6 in. 



Clay (shale) 10 ft. 



The shale that has been used for several years southwest of the city, in the 

 manufacture of vitrified bricks, is under a bed of limestone, and is probably 

 one of the layers shown in one of the river sections; but concretions of limonite 

 found in the original brick-bed are not so conspicuous elsewhere. Away from 

 the river the sandstone shows and is given in the following record of a deep 

 boring, made several years ago by the city: 



Record of strata passed through in Atchison deep boring: 



Thickness Total 

 of strata. depth. 



Sandrock 24 24 



Limestone 10 o4 



Red shale 10 44 



Soapstone 5 49 



Limestone 2 51 



Soapstone 20 71 



Sandrock 5 76 



Soapstone 64 140 



Limestone 2 142 



Soapstone 90 232 



Limestone 2 234 



Black shale 1 235 



Soapstone 7 242 



