704 GEOLOGY OF OHIO. 
Special activity is being now manifested in the introduction of new and 
ornamental forms. They may be classified as: 
Plain. 
Brick — | Pressed. 
Glazed. ssa 
f a oofing tile. 
| Solid Flooring tile. 
Tile— }; Building tile. 
| Hollow — | Bn proofing. 
l Flue linings. 
All these forms are being produced inthe State. The manufacture 
of common brick will not be considered here, inasmuch as the pro- 
cesses are primitive in their simplicity and are to be found everywhere. 
PRESSED BRICK. 
This is one of the newer departments of building material manutac- 
tures, but itis making rapid progress. The largest center of manufacture 
is at Zanesville, Muskingum county, where the natural facilities have 
been utilized by two large firms, Messrs. Harris Bros., and T. B. 
Townsend & Co. The former is the largest, and is probably as large as 
any any one brick establishment in Ohio. Under this firm, three yards 
in close proximity are maintained, with a working force of about one 
hundred men, and a daily capacity of 30,000 brick, common and pressed, 
equivalent to about 9,000,000 a year. ‘The process employed is an 
admirable one, and could be more widely used with advantage. The 
clay, which is probably not far from the level of the Lower Freeport 
horizon, though there are no coal streaks near by to identify it, is yelluw 
and irony ; very like the best clays of the drift, though it is a true bedded 
formation. In its situation it lies within 10 feet of the surface on the 
tops of several ridges near the town, and it may be an ordinary fire-clay 
vein weathered to the state in which it is found. It is dug and thrown 
back in loosely-piled heaps, so that it may further soften and weather. 
Enough is kept dug to allow it to weather a year before using. It i 
hauled to the works near by, and is then put into a soaking vat. This 
consists of a semi-circular depression 3 feet deep, and whose diameter 
is 30 feet. In the center of the diameter stands a pug-mill delivering 
away from the vat. This pit is filled with clay by dumping in succes- 
sive cart-loads from the circumference ; when full, the vat is flooded 
from a hose near by until the amount added will make the whole into a 
stiff mud. It soaks all night in this way in summer; in winter, wate 
