758 GEOLOGY OF OHIO. 
This indicates a quality superior to that of the Connellsville coke, in 
which there is usually 1 per cent. of sulphur, and 10 to 14 per cent. of 
ash. 
Hight or ten inches above the top of the coal, in this mine, is a band 
of impure coal six inches thick, containing roots of stigmaria. At a dis- 
tance of twelve hundred feet from the shaft it joins the main seam, but 
separates from it again thirty feet further on. 
At the Jefferson Iron Works (Spaulding, Woodward & Co.), the shaft 
is said by Mr. C. R. Thomson, superintendent of the mine, to be one hun- 
dred and eighty-seven feet seven inches to the coal. The coal is three 
feet eight inches in thickness, with a parting eight to nine inches from 
the bottom. At the time the examination was made, ninety-five hands, 
miners and putters, were employed inside the mine. Most of the coal 
raised was consumed in the extensive iron works of the proprietors. 
The fuel used in the furnaces is coke, one hundred and twenty ovens 
being in operation to produce it. These are circulars ten and a half feet 
in diameter, with thirty-six-inch spring of arch above wall, five and a 
half feet deep in clear under the ring. Charge: seventy-five bushels of 
coal, drawn after forty-eight hours burning, and yielding ninety-five 
bushels of coke. In the furnaces ninety bushels of coke are consumed 
to manufacture a ton of iron. | 
In the mine of the Jefferson lron Company an effort has been made to 
drive galleries under the Ohio to reach coal lands on the other side. 
This has not been fully accomplished, but, in the judgment of the pro- 
prietors, all difficulties have been overcome, and no obstacles oppose the 
extension of their works as far eastward as may be deemed advisable. 
Jt should be said, however, that until the low lands on the east side of 
the river shall have been passed, it will not be demonstrated that no 
old channel exists deep enough to cut out the coal. It has been sup- 
posed that the old channel was here not less than one hundred and fifty 
feet. deep, since the channels of some of the tributaries of the Ohio at 
points above Steubenville have been found cut to about that depth below 
the present streams;.but the surface where these deep channels are 
known to occur is very much higher than at Steubenville, and conse- 
quently free drainage would be afforded to the tributaries above, even if 
the buried channel of the Ohio was not more than one hundred feet 
deep. At and below Cincinnati, borings have shown that the old chan- 
nel is at least one hundred feet deep. This, taken in connection with 
the borings made on the Upper Allegheny and Beaver, have led to the 
inference that the old channel was from one hundred to one hundred 
and fifty feet deep at Steubenville, but the facts presented by the mine 
