IRON MANUFACIURE. 485 
in the region where raw coal was used with continued success, and 
where it has been employed since 1866. There are now in Jackson four 
blast-furnaces using this fuel, and the native ores of the region, viz., 
the Star, Fulton, Globe and Tropic, all the result of the enterprise of the 
vicinity, but they are of quite moderate dimensions. Second, Portsmouth 
on the Ohio, st the mouth of the Little Scioto River, and beyond the 
western margin of the Coal Measures. Though containing two large 
rolling-mills, foundries, etc., it is more important as the chief com- 
mercial town of the region than as a manufacturing center. Being the 
terminus of the Portsmouth branch of the Cincinnati and Marietta Rail- 
road, Portsmouth is the shipping place and business center of a large 
number of furnaces in the western part of the iron region. As 
almost every article of supplies necessary for the maintainance of the 
furnace population is derived from the adjoining parts of the State, the 
Scioto Valley, etc., the return trade is of very great importance, and in 
this, Portsmouth is the chief market of the region. Third, Ironton, in 
Lawrence county, 30 miles up the river from Portsmouth, in 1871 a 
city of 7,000 inhabitants, is the most important and enterprising manu- 
facturing point in Southern Ohio, besides being the shipping and 
distributing center for the most important part of the Hanging Rock 
region in Ohio. It is the largest town on the Ohio River above Cin- 
cinnati which has navigation uninterrupted by the fluctuations of 
the height of the water. 
The general position of the iron ores of the region has already been 
referred to. Very detailed sections, showing their relative positions, 
may be seen in the reports of the included counties by Prof. Andrews 
in other portions of the Geological Reports, but a short notice may, how- 
ever, be given here of the situation, character and mode of mining of the 
principal ores, while analyses will be given in a subsequent part of this 
report. 
All the principal ores are found within 300 feet of the base of the 
Coal Measures, and the most important horizon, as regards the value of 
the ore and the persistency of its development, the horizon of the “ lime- 
stone ore” has already been mentioned as the probable equivalent of 
the ferriferous limestone of Northwestern Pennsylvania. 
The ores are limonites or hydrous peroxides of iron, and to a 
smaller extent, calcareous and argillaceous carbonates. The beds were, 
however, in their original condition as ores, probably all carbonates, 
