1010 GEOLOGY OF OHIO. 
Conglomerate can no longer be counted an undivided stratum, but it is 
rather a complex and much varied formation. There is no single 
stratum of pebble rock in the State that has any longer a right to be 
called “the Conglomerate ”’. 
But there seems no good reason to call in question the assertion 
that as the Shaft coal les below, the Hill coal is above the conglome- 
rate sandstone already named. 
The conglomerates that enclose the Jackson shaft coal answer well 
for the Sharon and Massillon (Conoquennessing) divisions respectively 
of the great Conglomerate formation of the Pennsylvania scale. 
In my report upon the Hanging Rock district in 1877, Vol. III, 
page 885, a mischievous and confusing error appears in all of the 
sections involving this part of the scale. The Jackson Shaft coal and 
the Wellston coal are represented as lying below the Maxville lime- 
stone. The real order is given in the preceding statement. 
Counting from the Lower Mercer limestone, which is the one con- 
stant and reliable stratum through the field, the Wellston coal is about 
110 to 120 feet below it in the scale. The Jackson Shaft coal may be 
provisionally counted as about 75 to 100 feet below the Wellston coal. 
Larger and smaller measures than these are often found. Counting 
from the nearest exposures of the Hill coal to the floor of the mines 
under Jackson Court House, an interval of 175 feet has been deduced, 
but as has been said, the distance is too great between the exposures 
to make the measurement a safe one. One mile beyond Jackson, the 
interval from an unquestioned body of the Shaft seam found in a drill- 
hole on the land of Ambrose L. Scott, to the blue limestone (Lower 
Mercer) is but 140 feet, or within 20 or 30 feet of the place of the 
Wellston coal, but this is certainly abnormal and unusual. 
There is, fortunately, much greater certainty as to the order above 
the Wellston coal. ‘The leading horizons of the Lower Coal Measures 
are easily identified in the main throughout the county. 
The mining interests and present development of the Jackson 
Shaft and the Wellston coal fields are well treated in the following 
section, prepared for this chapter by Hon. Andrew Roy, late State 
Inspector of Mines. He has confined his description to the basin 
already developed. Others are known and worked in a small way, 
and if made accessible by railroads, their coals may become valuable. 
Prominent among these outlying fields is the Hamilton township basin, 
