70 GEOLOGICAL RECONNOISSANCE 



The base of Coal-hill consists of black and ferruginous shales, sur- 

 mounted by thick-bedded sandstone, capping its summit. 



Ferruginous shales are strewed on the slope, under the sandstone, for 

 seventy -live feet. Beneath this, for the depth of five feet, is a bluish shale, 

 enclosing oval concretions. 



The immediate roof of the coal is a peculiar, rusty, talcous-looking, 

 scaly shale, unctuous to the touch, and crumbling to pieces with the least 

 friction. 



The coal varies from ten to twelve inches in thickness. 



The base of the hill, for 60 feet under the coal, is composed of dark, 

 bluish-grey shale, including considerable quantities of carbonate of iron. 



The same bed of coal crops out on the western declivity of Coal-hill. 



This coal has been partially opened for the use of the blacksmiths in 

 this part of White, and the adjacent portion of Conway county, but where 

 it has been worked, it has not afforded a coal altogether free from the 

 pyritiferous impurities required for shop use; the thickness, too, is not 

 sufficient to warrant the expense of running drifts into it for any great 

 distance. 



Sandstone occupies the surface at Rocky point, but shale is reached 

 about eight or nine feet under the surface. A similar sandstone crops out 

 on the slope descending to Cypress bayou, on the confines of White and 

 Prairie counties. All these strata are, no doubt, referrible to the millstone 

 grit series at the base of the coal measures. 



Ascending from the waters of the Cadron and Des Arc, in the western 

 part of White county, a great mass of variegated and ferruginous shales 

 is encountered, nearly two hundred feet in thickness, including some inter- 

 calated bands of sandstone. These are surmounted by some fifty feet of 

 heavily bedded sandstones, which are again overlapped with shales and 

 schistose siliceous rocks, capping the mountain near the widow Norman's. 

 Four and a half miles beyond, in the neighborhood of Theodore Good- 

 low's, the sandstone on the table-land is characterized by peculiar vermi- 

 cular impressions,* such as were observed in Hancock county, Kentucky, 

 in the first bench of sandstone under the main Ilawesville coal, and about 

 50 feet above the bench of underlying conglomerate. This bench of 

 sandstone lies, therefore, at the base of the coal measures, and though 

 there is a thin bed of coal beneath this sandstone at Ilawesville, it may 

 be considered as underlying the productive coal measures, since no work- 

 able bed of coal has yet been found below it. 



* These impressions are probably referrible to some species of fucoids or seaweeds. They bear 

 some resemblance to drawings of Phytogyra, but are apparently single and more simple in their 

 structure than that genus. 



