66 GEOLOGY OF OHIO. 
for many years. At Uhrichsville it is found in the valley of the Still- 
water from twenty-five to thirty feet below Coal No. 6, three feet in 
thickness; it is here and at Dennison, according to the borings, ninety 
feet above the limestone. | 
On the east side of the Tuscarzwas valley, below New Philadelphia, 
Coal No. 5 seems to be thin, and is scarcely worked at all. The same is 
true of all the region lying between the valley of: the Tuscarawas, and 
that of the Conotton, and it is doubtful whether this.coal has much value 
south of Zoar Station and west of the Conotton. On the east side of the 
Conotton, over a large area, between Waynesburg, Mineral Point, and 
New Cumberland, it seems to be of good quality and thickness. 
Fire-clay.cBeneath Coal No. 5 is the most valuable bed of fire-clay in~ 
the series, and one that now serves as a basis for an important branch of 
manufacture at Mineral Point and Dover. This fire-clay-is always good, 
but it exhibits considerable diversity of character. In some localities it 
is quite plastic, while in others it is ‘‘non-plastic” or “flint” clay, is 
free from injurious ingredients, and has been found to form a very supe- 
rior material for the manufacture of fire-brick. This hard clay may be 
recognized by its having somewhat the appearance of flint, and instead 
of softening down to a paste, like most fire-clays, it breaks into small 
angular fragments. In this respect it resembles the clay from which the 
famous Mt. Savage fire-brick is made, and it seems to be of equally good 
quality. When used for the manufacture of brick, it is coarsely ground, 
and the fragments are then mixed with from one-sixth to one-tenth of 
plastic clay, by which they are made to adhere and hold the form of the 
mold. Large fire-brick factories are now in operation at Dover and Min- 
eral Point. The first is owned by Messrs. Barrett & Rhodes, and the second 
by Mr. C. EH. Holden. From ali the trials made of the fire-brick manufac- 
tured at these localities, they are now reckoned not inferior in quality to 
the Amboy or Mt. Savage brick. The clay used by Mr. Holden is mined 
on his own property, at Mineral Point; that used at Dover, is obtained 
from the land of Geo. Lechner, at Mineral Point, and on the Watman 
farm, between Dover and Zoar. The same stratum of hard clay is opened 
near Bolivar, and supplies the material from which the “Bolivar Star 
Brick” are made. 
A considerable quantity of the hard or “flint” clay is shipped from 
Mineral Point, for manufacture in other counties. Much of it goes to 
Akron, where it is largely used by Mr. J. Parke Alexander, in one of the 
-yarieties of excellent fire-brick made by him. 
Iron Ore.—Coal No. 5 is usually overlain by a black or gray shale, 
which contains a notable quantity of iron, and this horizon has fur- 
