r. 
FAIRFIELD COUNTY. 593 
nearly the center of Madison, and empties into the Hocking River in 
Hocking county. 
Drift.—The whole county may be included within the area of the 
Drift. In the lower grounds we find in sinking wells the blue Drift 
clays, and every where are to be seen the gravel and bowlders of the 
Drift period. The quantity of Drift materials originally brought into 
the county must have been immense, for from the heads of the Hocking 
must have been obtained the supply of sand and gravel needed to form 
the vast gravel terraces which skirt the river to its mouth. Bowlders 
are found every where in the lowlands and on the highlands. They are 
of all sizes, from that of the famous one on Baldwin’s Run, a little east 
of Lancaster, which is approximately eighteen feet by sixteen feet in its 
two diameters, down to those only a few inches through. They are gran- 
ites, diorites, quartzites, and other hard rocks, capable of enduring the 
rough usage to which they have been subjected since first they were 
broken from their original beds far north of the lakes. In some cases 
the bowlders are limestone, and so abundant that they are broken up and 
burned for quicklime. This has been done to a considerable extent in 
Fairfield county. 
In. the immediate valley of the Hocking we find ae modified Drift in 
the form of sand and gravel terraces, which were once great sand flats 
and bars, formed by the stream when it stood from eighty to one hundred 
feet higher than now. Much of the city of Lancaster is built upon such 
a terrace. Underneath the sand and gravel, and elsewhere in the lower 
grounds, we often find the blue Drift clay containing scattered bowlders. 
In this clay we obtain trunks of trees, roots, twigs, etc., generally of conif- 
erous type. They represent the vegetation which grew in the valleys 
or along the hill-sides at the beginning of the Drift era. Many speci- 
mens of such buried wood have been found in sinking wells in Lancaster. 
The foregoing are the leading facts of Drift phenomena in Fairfield. 
The general subject of the Drift and of Drift agencies is more fully con- 
sidered in Chapter L., in this volume of the Report. 
The geology of Fairfield county is very simple. The county hes wholly 
within the range of the Waverly formation, with a trifling exception of 
a very limited area in the extreme eastern edge of the county. This 
exception is found on the high hill in the neighborhood of Hast Rush- 
ville. Here, south of the village, we find a thin seam of coal, and other 
rocks characterizing the Coal Measures. It is possible that in the east- 
ern edge of Rush Creek township there may be some hill-tops which be- 
long to the same formation. There are, however, no available coal seams 
in the county. 
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