452 GEOLOGY OF OHIO. 
coke, lacking density and hardness. Mr. Himrod, however, coked it 
in heaps or ricks, and at first used it in the furnace mixed with char- 
coal, and finally entirely alone with perfect success, both as regards the 
working of the furnace and the character of the iron. Soon, however, 
they were met with an additional trouble, for, the cokers striking, they 
were obliged either to go out of blast or attempt to use the coal without 
coking, the latter being determined upon. The raw coal was at first 
mixed with coke, and at last was used alone. These experiments 
were watched with the greatest interest by others, and when, by the 
results of the trial, the suitability of raw coal for use in the furnace was 
established, this material was soon adopted by other furnaces in the 
Shenango and adjoining Mahoning Valley. The Clay Furnace was 
the first furnace in the United States to use bituminous coal in the raw 
state. In Scotland, however, raw bituminous coal had been used 
extensively for a number of years (at least since 1828), and in Central 
England and South Wales probably for a longer time. In Ohio the 
first iron made with raw coal was produced at the Mahoning Furnace 
at Lowellville, some 7 miles southeast from Youngstown, about one 
year after the success of the Clay Furnace, or in August, 1846. This 
furnace was built in 1845 by Messrs. Wilkes, Wilkinson & Co., and 
continued to use coal from the old Mt. Nebo mines until their abandon- 
ment a few years since. Following the favorable results at the Clay 
and Mahoning Furnaces with the employment of block coal, other fur- 
naces were erected for its use until it became the basis of the most 
important iron district in the State, and in 1873 there were nearly fifty 
furnaces dependent upon it in Northeastern Ohio and Northern Penn- 
sylvania. 
These conditions continued in Northern Ohio for some ten years 
without any great change, excepting the more general employment of 
the block coal, until 1856, when the first development of the iron ores 
of Lake Superior opened up a new source from which to obtain iron 
ores, and to compensate in part for the sparsity of their distribution in 
this part of the State. Though the importance of the Lake Superior 
ores was acknowledged in 1845 by the formation of the Jackson Com- 
pany, it was not until 1856 that any regular shipments were made. 
However, a cargo is said to have been sent to the Clay Furnace in 1854, 
and Mr. Himrod states that the first iron was made from them in 1855. 
Although there was some unaccountable prejudice against their use at 
