OF ARKANSAS. 235 



CONWAY COUNTY. 



The- northern part of Conway county is skirted bj a continuation of the 

 same chain of mountains that traverse the preceding counties of Pope 

 and Johnson, and has a corresponding geological structure. Sandstones 

 of the millstone grit form its summit, overlying flagstones and shale. 

 The hills diminish very much in the southern part of the county, seldom 

 exceeding three hundred feet, and are composed mostly of thin-bedded 

 sandstones, underlaid by reddish siliceous, and dark argillaceous shales. 

 In the level portions of the eastern part of the county, the latter shaly 

 members underlie the fine tracts of grass land, which affords excellent pastu- 

 rage for cattle. 



Thin beds of coal have been opened, in many places, on the waters of 

 the Cadron, in the eastern part of the county, and range in thickness from 

 4 inches up to 20 inches. In section 7, township 5 north, range 12 west, 

 on the Black fork of the Cadron, a 4 inch seam of coal is intercalated 

 amongst the shales. It is a more solid coal than those beds previously 

 described, in Pope and Johnson counties, highly bituminous and very 

 black; it has but little tendency to crumble, and breaks with a smooth 

 angular fracture. A few fossil plants were found in its roof shales, 

 belonging to the genus pecopteris and n uropt ris. This is probably a 

 different seam of coal from that, before mentioned, on Illinois bayou and 

 the waters of Horsehead creek. It is, however, too thin a seam to be of 

 much commercial value. 



Three layers of subcarboniferous limestone crop out on Turkey creek, 

 a branch of the Cadron, in all four or five feet thick, dipping about 3 deg. 

 south-east. It is a dark, earthy-looking rock, containing encrinite stems 

 and indistinct carboniferous fossils. This is the only limestone that has 

 been observed, south of Little Red river and north of the Arkansas river, 

 in this part of the State; as this rock will make a good strong lime, it is 

 important to a country where limestones are seldom accessible. 



In the north-east part of Conway county, close to the Bull mountain, 

 the dark shales under the millstone grit are fractured, dislocated, and 

 traversed by veins of quartz, associated with talc and other allied mag- 

 nesian minerals; the shales, for some distance on either side of these 

 veins, are indurated, altered, and more or less metamorphosed. I observed, 

 at one locality, an almost vertical bank of dark, siliceous rock, one foot 

 wide, charged with iron, and possessing a cubical structure, the blocks 



