2, GEOLOGY OF OHIO. 
on the west side of the valley, over and south of the mine of Mr. Andreas, 
the sandstone is well developed, in places reaching a thickness of seven- 
ty-five feet. 3 
In most places where the Mahoning sandstone is not very thick, traces 
of a coal seam may often be found, about fifty feet above Coal No. 6. In 
the northern and central portions of the county this is not well shown, 
but in the southern townships it is thicker and more constant, in places 
forming a workable and valuable coal, which we have designated as No. 
6a. In the hill above Dennison it is sean in the road, overlain by a 
brecciated limestone, which is unlike anything found lower in the series. 
_ The coal is here too thin to be of much value. Further south, at Wal- 
_lace’s, near Newport, it is two and a half feet in thickness. In this 
vicinity it lies from twenty to thirty feet below Coal No. 7, the intervals 
being filled by the brecciated limestone, referred to above, two or three 
feet in thickness, argillaceous shales, and the fire-clay of No. 7. | 
Coat No. 7, AND ITs [Ron OREs. 
This coal is quite a constant feature in the sections exposed in 
' Tuscarawas county, but throughout the northern and central townships, 
it has little economic value. On entering the county from the north, it 
is first seen in the tops of the hills about Zoar Station, and thence south- 
ward, is continuous in all the highlands to the Guernsey county line. 
Tt is locally known as the blackband coal, from the fact that the impor- 
tant blackband deposits of the county rest directly upon it, and hence 
its place is well known to a large part of the inhabitants. 
On the old furnace tract at Zoar Station, Coal No. 7 is three to 
three and a half feet in thickness, soft, sulphurous and poor. In the 
highlands, between the Conotton and the Tuscarawas, it is shown in all 
of the blackband ore mines, being usually taken out with the ore. It is 
here from one to two feet in thickness, and generally quite sulphurous. 
In the highlands west of the Tuscarawas, in the townships of Salem, 
Bucks, Auburn, and Sugar Creek, quite a large territory lies above the 
horizon of Coal No. 7, and it is opened at numerous localities, in connec- 
_ tion with the important deposits of blackband ore found there. Through- 
out this region, the coal is thin and poor. On the south side of the 
Tuscarawas, it improves greatly in thickness and quality, as it does to 
the east between Dennison and Leesburg. It has, however, nowhere in 
Tuscarawas county, the value that it has in Guernsey, where it is the 
“Cambridge Coal,” the most important of all the coal seams found there. 
In passing up the valley of the Stillwater, from Uhrichsville, Coal No. 
7 is first seen in the hill above Dennison, and is apparently about three 
