IRON OF PENNSYLVANIA AND OHIO. 331 
nati to many of the river counties. The furnaces 
on the Kentucky side of the Ohio River, in the iron 
ore region, are quite as numerous as those in that 
state, and assist in giving permanence and value to 
this new market. When the number of furnaces is 
quadrupled, as they in a short time must be, from the 
regularly increased demand for iron in railroads, 
steam-engines, &c., the value of the iron manufac- 
ture will be swelled to several millions, and the mar- 
ket for the productions of the soil be proportionally 
increased. So true is it that agriculture and manu- 
factures are twin sisters, and go hand in hand, afford- 
ing mutual benefit and assistance to each other."* 
It is computed that at least 12,000 square miles in 
the State of Ohio are underlaid by coal, and as much 
by beds of iron ore. Mr. Briggs, in his report to the 
Legislature of Ohio for 1838, remarks, " at a very low 
calculation of the amount of good iron ore in the re- 
gion which has this season been explored, it is equal 
to a solid unbroken stratum 61 miles in length, six 
miles in width, and three feet thick. A square mile 
of this layer being equivalent in round numbers to 
3,000,000 cubic yards ; when smelted, will yield as 
many tons of pig iron. This number, multiplied 
by the number of square miles contained in the stra- 
tum, will give 1,080,000,000 tons : which, from these 
counties alone, will yield annually, for 2700 years, 
400,000 tons of iron ; more than equal to the great- 
est amount made in England previous to the year 
1829." 
The states of Kentucky, Tennessee, Indiana, Illi- 
nois, Maryland, and Virginia, supply also inexhaust- 
ible quantities of iron ore ; and in Tennessee alone 
there are now annually manufactured nearly 100,000 
tons of iron; each furnace, of which there are now 
more than 30 in Middle Tennessee, producing an an- 
nual average of 1000 tons of metal per year. 
* First Annual Report on the Geol. Survey of Ohio, 1838. 
