254 GEOLOGY OF OHIO. 
are unmistakable evidences of a previous erosion of the rock surface, but 
in the western part of the county no such indications have been seen. 
Besides occasional irregularities in the surface of the bedded rocks, the 
manner of the deposition of the Drift was such as to leave very noticeable 
differences in 1ts condition and thickness in different parts of the county. 
In the sandstone region, and especially where the Berea grit forms a line 
of junction with the underlying shale, the Drift is coarse and stony, and 
the surface is broken. Frequent springs of ferriferous water issue from 
the hillsides, which seem to be very gravelly. The channels of the 
streams are deeply cut into the bed rock—plainly beyond the power of 
the present volume of water—and the valleys are marked by large bowl- 
ders. Such bowlders are found in the valleys in all parts of the county, 
but are much more noticeable in the sandstone district. Near South 
Woodbury, in the creek bottoms (lot 10), is a bowlder of fine-grained 
syenite, the extreme dimensions of which are nine feet by seven and a 
half feet, showing four and a half feet above the ground. In this bowl- 
der hornblende predominates, and the feldspar is flesh-colored, quartz 
being scarce, giving a rather dark color to the whole. In the western 
part of the county, however, where the surface is underlain by shale or 
by the black slate, the Drift is more evenly spread, and the country is 
flat. The streams have Gin very much the same manner, though not to 
the same extent) cut their channels into the bed rock, but they are fewer 
in number, and have a less average descent to the mile. The water of 
wells and natural springs is apt to be sulphurous, and bubbles and jets of 
gas are very often met with. In some marshy places an inflammable 
gas rises spontaneously, though this is not known to be the same as that 
which rises from the shale below the Drift. The surface is clayey, and 
the soil needs artificial drainage. 
The following observations for altitude, by aneroid barometer, are re- 
ferred to the level of Lake Erie through Mt. Gilead Station, the height 
of which is given at 466 feet by the Cleveland, Columbus, and Cincin- 
nati Railroad: 
Above Above 
Lake Erie. the Ocean. 
Mite Gulead@Stationsrrketa maces norcteseeeatnoetecinee a enes 466 feet. 1031 feet. 
SillkoteNationaleHiousemVits Galleadanen..ccsssc loses Dil Oe 
Greelaat tine mani Vita Galleadeetamesncceteenccsccesiees BO BG 
Creek at south bridge, Mt. Gilead............... .cssceecoes 306 ? * Opal ey 
Summit of ridge 14 miles north of Franklin Center, 
SECH OMA, Param kdl eee see meee ennten too tnacecsyerenont cones G25 eles LOO 
Summit of ridge, Franklin Center...............20. s.eseees gy) 1164 ‘ 
Chesterville, Main street............00: esessens cooese sooees cee 3200s 885 “ 
@hrestenvailllewbedtotecreekiecemenceerecchetiecericcsesttreas BIG Solas 
Bloomfield Cemetery, N. W. 4 section 17 ........0 see SVGMa 1141 “ 
