162 GEOLOGY OF OHIO. 
area of the upper coals, one or both of them are usually present, except 
where locally cut out by beds of sandstone. Coal No. 9 lies immediately 
upon the limestone over the Pittsburgh coal, and this limestone thins 
toward the north and west, letting down Coal No. 9 on to Coal No. 8. At 
Cadiz, Harrison county, Coal No. 9 is two feet thick; at York, Jefferson 
county, it is one and a half feet thick; at Unionport and Knoxville, in 
Jefferson county, it has disappeared, and Coal No. 8 is covered in one place 
by 85 feet and in the other by 100 feet of sandstone and shale, upon which 
Coal No. 10 rests. Toward the west from Wheeling, Coal No. 9 seems to 
disappear, and the interval between the Pittsburgh seam and Coal No. 10 
is represented by Prof. Stevenson to be, in western Belmont and Harrison 
counties, filled by a great mass of sandstone, in places more than 100 feet 
in thickness. This sandstone, he says, has been deposited by currents 
which have extensively cut away Coal No. 9 and, locally, Coal No. 8. 
Coal No. 10 is a very persistent seam, and locally attains considerable 
importance; but in Harrison, Jefferson, and Belmont it is of far less 
value than the Pittsburgh seam. {It is frequently a double bed. At 
Badgersburg the coal is six feet seven inches thick, in twe benches, sepa- 
rated by one foot eight inches of shale.and clay. At Flushing the upper 
bench is one foot two inches, the parting one foot four inches, and the 
lower coal three to four feet in thickness. At New Athens, Harrison 
county, the seam is divided into three benches, of which the upper is 
ten inches, the middle four feet eight inches, and the lowest four inches, 
the partings being respectively two feet and three feet in thickness. In 
Jefferson county Coal No. 10 becomes much thinner, and it is little more 
than a bituminous shale, two to three feet thick. (Stevenson.) 
What the extension of Coal No. 10 toward the south and west is, can- 
not be accurately stated. We have reason to believe, however, that it is 
the same as that mined at Cumberland, Muskingum county, called by 
Prof. Andrews the Cumberland coal. This lies, according to his descrip- 
tion, about 100 feet above Coal No. 8, and runs through the counties of 
Morgan, Athens, and Meigs, to the Qhio river. In this region it varies 
from two to six feet in thickness, and is frequently divided by one or 
more partings of clay or shale. It usually is associated with much lime- 
stone, above and below, and Mr. W. J. Herdman, who traced it through 
nearly to the Ohio river, has furnished me a section from Morgan county, 
in which the Cumberland seam is everlaid by 160 feet of strata, largely 
made up of limestone. 
Coal No. 11 has been referred to in a preceding page as the represent- 
ative of the Waynesburg and the ‘jumping six-foot seam.” It is locally 
ef some economic value in Belmont county, but both in quality and 
