GEOLOGY OF OHIO. 727 
at the point where the railroad crosses Yellow Creek. At the Empire 
Mine, it is apparently wanting, as the air shaft shows a limestone 
twenty feet above the coal mined (No. 6). This limestone is apparently 
the same as that seen at the railroad bridge, and as there without any 
coal above it. Ina boring made at the Empire Mine, limestone four 
feet thick occurs immediately beneath the fire-clay of the coal, just as 
in the central and eastern portions of Columbiana county. At Irondale 
coal No. 7 is 24 feet thick; at Collinwood, from 3 to4 feet; at Linton, 
where it is known as the “ Groff Coal,’ from 3 to 44 feet. Along the 
river between Yellow Creek and Wills Creek, Coal No.7 appears at 
various places—Elliotsville, Sloan’s Station, Brown’s Station, etc.— 
and varies from 24 to 4 feet in thickness. At Fleming’s Mine, above 
Brown’s Station, it is very well shown and 4 feet thick. At Wills Creek 
it has come down nearly to the level of the river, and is three feet in 
thickness. At Yocum’s Well, just south of Wills Creek, it is reported to 
have been passed in boring, and to have been about 2 feet thick. At 
and below Steubenville, it is either wanting or too thin to be worked. 
On the south side of the river, Coal No. 7 has apparently been identi- 
fied at Tomlinson’s Run, and at New Cumberland, and is there from 3 to 
5 feet in thickness. 
The interval between Coal No. 7 and the “ Big Vein ’”—No 6, is at 
Salineville from 50 to 62 feet; at Irondale it is 50 feet; at Collinwood it 
is reported to be 35 feet only; at Linton 65 feet; at mouth of Wills 
Creek it is 62 feet. 
Coal No. 6.—The “Big Vein” of the northern part of Jefferson county, 
the “Shaft coal” of Steubenville and Rush Run, is the thickest and most 
valuable coal found in this region. Its thickness at Salineville varies 
from three to six feet, at Kirk’s salt well showing the latter, while at the 
Empire Mine the maximum thickness is five feet nine inches, average 
thickness about five feet. At Irondale it is five and a half feet, at Linton 
six to seven feet, at Steubenville it is four feet in thickness, at LaGrange 
five and a quarter feet, and at Rush Run six to nine. In all the north- 
ern part of the county the coal of seam No. 6 is highly cementing, and 
contains considerable sulphur. At Steubenville it is a very pure, par- 
tially open-burning coal, largely used, when coked, for the manufacture 
of iron. This seam is rarely homogeneous and almost always shows a 
parting of slate or bony coal at or below the middle. 
Coal No. 5.—This is known on Yellow Creek as the “Roger Vein.” It 
is there from two and a half to three and a half feet in thickness, of 
medium quality, and has been worked only for local use. The interval 
that separates No. 5 from No. 6 is quite variable, ranging from thirty-five 
