956 GEOLOGY OF OHIO. 
The ordinary measure falls a few inches below these figures, and 
on the north-eastern side of the mine the uppermost bench is wanting 
for a considerable area, reducing the seam to 7 or 7% feet. 
_ The parting between the normal and supplemental seams is every- 
-where found. The upper bench of the normal seam is generally thicker 
than it is shown in the figure, there being nearly a foot to be rejected 
here, including the second slate. 
The coal of both of these properties was found to be seriously 
interrupted in the front hill, by sandstone ‘‘ horsebacks” proceeding 
from the roof, and by the associated clay veins that rise from the floor, 
and large outlays nave been incurred in driving through the low coal 
and the rock. The direction of the sandstone channels is approximately 
south-west, but the clay veins, though associated with and apparently 
due to the descending rock, are irregular in their boundaries, and are, 
therefore, much more confusing than the sandstone faults. 
These mines, among others, illustrate the modes in which ultimate 
loss is incurred by unskillful management in mining. ‘The coal of this 
field is easy of attack, and, at the outset, mines seem to have been lo- 
cated and worked with reference to immediate results, without definite 
and well-considered plans as to their continuous operation. As a 
consequence, it has been found necessary already to shift, at large ex- 
pense, tipples and tracks, while the underground workings present a 
dreary display of weakened and endangered entries, for which adequate 
protection can not now be easily secured, and a wilderness of lost 
pillars and props. Blocks of coal are also cut off, occasionally, from 
their natural routes of egress, and can be gained only by increased 
expense. The amount of coal needlessly sacrificed in the Straitsville 
mines, by want of proper knowledge and skill in opening and managing 
them, will reach a high figure. It this field had been, from the first, 
handled with the same care and skill that characterize its recent 
management, it would have made its present value greater by more 
than 200 acres of solid coal. In other words, more than 200 acres of 
coal have been needlessly lost to the field. 
The front hills of these two properties have been almost entirely 
worked out, and the solid coal lies a half mile or more from the tipples. 
More than 200 miners are now engaged in drawing stubs and pillars in 
these mines. In many cases the coal has become “croppy” by long 
exposure, and can no longer go into market as first-class fuel. 
