THE CARBONIFEROUS SYSTEM. 159 
above the river and Coal No. 6, and reaches to about the south line of 
Carroll. Going thence southward, it exhibits two lines of outcrop, one 
in the valley of the Ohio, the other traversing the interior in a tortuous 
but generally south-west direction. At Knoxville and Richmond the 
coal seam is from three to four and a half feet in thickness, generally with 
little cover and of poor quality; thence to Steubenville it is interrupted 
but southward from this point it is mined almost continuously to and 
below Wheeling. The dipishererapid. At Mingo it hes 360 feet above 
the river, 513 feet above Coal No. 6, where mined in the shaft. At 
Lagrange it is a little higher than at Mingo, being 378 feet above the 
Ohio. At Rush Run it is 306 feet above the river, 511 feet above Coal 
No. 6. At Tiltonville it is 230, Martin’s Ferry 148, Kirkwood 185, and 
at Bellaire 120 feet above the river level. At Wegee it is 15 feet, and at 
Moundsville 80 feet below the Ohio. Throughout this region its thick- 
ness varies from five to nine feet, the coal varying somewhat in quality, 
but always highly coking. It is generally a double bed, consisting of 
two or more beds separated by partings of fire-clay or shale. 
Along its western line of outcrop Coal No. 8 passes through Jefferson, 
Harrison, and Belmont into Guernsey, where it crosses the Baltimore 
and Ohio Railroad. It also forms several outliers, or small islands, in 
Guernsey, produced by the folds in the strata, to which reference has 
been already made. South of the railroad it passes through Muskingum, 
Morgan, Athens, and Meigs to Pomeroy, where it crosses the Ohio, and 
is extensively mined. Throughout this long line of outcrop the Pitts- 
burgh coal may be said to be continuous, though it exhibits considerable 
local diversity of dimensions and character. In Muskingum county it is 
quite thin, sometimes not more than one foot in thickness, and it is evi- 
dent that we are there on the extreme western margin of the great basin 
in which it was formed. In Morgan, Athens, and Meigs counties, the 
Pittsburgh, or Pomeroy, seam assumes much greater importance, varying 
from five to nine feet in thickness. It is there often divided by one or 
several partings, as it is so prone to be elsewhere. In Homer township, 
Morgan county, it is reported by Prof. Andrews to have an ageregate 
thickness of eight to nine feet in two nearly equal benches, with a clay 
parting of one foot. On Federal Creek, Bearne township, Athens county, 
the Pomeroy seam is from eight to nine feet thick, exclusive of a parting 
of shale and clay one foot or more in thickness. The coal is here bright, 
black, and of a very serviceable quality. It has the typical character of 
the Pittsburgh coal, being highly coking, but with more sulphur than 
at Pittsburgh or Pomeroy. In other localities in Athens and Morgan 
the seam is smaller, is ih without ee and furnishes a very 
pure and useful coal. : 
