CPIAPTER LXXXIX. 



SUPPLEMENTAL REPORT ON THE GEOLOGY OP THE 

 HANGING ROCK DISTRICT. 



BY EDWARD OHTON, ASSlSfANT GKOLOGIST. 



A heavy sandstone covers Coal No. 6 through a confiderable part 

 of its outcrop in Ohio. In Lawrence county this rock is well developed, 

 especially in those portions that border on the Ohio River. Near the 

 village of Hanging Rock it shows itself ia very held and picturesque 

 escarpments, from which the village derives its name. 



The manufacture of pig iron in Southern Ohio was begun on Brush- 

 Creek, in Adams county, but the supply of ore found there, derived from 

 Upper Silurian limestones, proved limited and uncertain, and it wasmot 

 long until the seat of the manufacture was transferred to the western 

 border of the Coal Measures in Scioto and Lawrence counties. A very 

 prosperous and important industry was soon developed here. Several of 

 the earliest furnaces were located near Hanging Rock, and their iron 

 was distributed from that point as a center by means of river transpor- 

 tation. The products of these furnaces was thus known as far back as 

 fifty years ago as the " Hanging Rock Iron." The name was naturally- 

 extended so as to include all the iron made from the general geological 

 horizons that were worked by these earliest furnaces. These horizons 

 were gradually followed back from the river through county after county, as 

 far as the Hocking Valley, the old Logan Furnace being the last one 

 whose iron was counted Ha.nging Rock-Iron. 



The belt of country thus occupied is about sixty- five miles long and;, 

 from ten to twen-ty miles in breadth, its longer axis bsaring abjut 

 twenty degrees west of south. Upon it fifty furnaces have been estab- 

 blished, and the best of the iron made in them has become the standard of 

 comparison throughout a large ponion of the Mississippi Valley. For 

 some important uses, indeed, there is good reason to believe that no; 

 better iron has ever been manufactured in the country; ... i 



The ore seamS that have been worked in the Hanging Rook diatrlct.i 

 are very numerous, but one saam enjoys. such easy, and undispiited' 



