SHELBY COUNTY. . 459 
seat, near the end of the bridge over the river, as before stated, is near 
sixty feet below the canal, these figures would give to the Clinton a 
rise in level with horizon of about thirty feet in that distance. 
The surface of bedded rock underlying the Drift in Shelby county is 
doubtless worn unevenly, in some places rising above the level indicated 
by the top rock, on the Miami, below Sidney, in others sinking more or. 
less below that level—perhaps, in places, greatly below. 
Rising sometimes to one hundred and sixty-four feet, maintained gen- 
erally at a level ranging from figures but a little lower than this, down 
to seventy-five feet (seldom going lower), we may conclude that there is 
an average depth of Drift in the county of one hundred feet. This depth 
of Drift is not equaled in any of the counties which he south of this. 
We are here on the line which bounds the deep Drift on the south. 
The opportunities to ascertain the nature of the Drift are numerous In 
the excavations made in constructing the canal and railroads, especially 
the Indianapolis and Bellefontaine branch of the Cleveland, Columbus, 
Cincinnati and Indianapolis Railroad, which runs at a considerably . 
lower level than the Dayton and Michigan road, which runs through the 
county in a north and south direction. At the point where the east and 
west road runs below the track of the Dayton and Michigan, on the 
western border of Sidney, a good opportunity is afforded of seeing the 
nature of the Drift for a distance of thirty or forty feet below the surface. 
_About one mile east of the bridge over the river, on this road, is a still 
deeper cut. There is little stratification observed in the deposit as seen 
through these deep cuts. Sand and gravel largely predominate in the 
composition of the Drift as seen here, mixed with clay and numerous 
granitic or quartz bowlders, varying in size from mere pebbles to masses 
containing from ten to twenty cubic feet. The gravel, sand, and bowl- 
ders are distributed through the clay, and all are lying in confusion. It 
seems to me safe to say that fully twenty-five feet in thickness of clear 
gravel, were it separated from the clay, would be found in the Drift 
throughout this county—a quantity so inconceivably great that I will 
not undertake to express it in figures, more than to say that it would 
yield twenty-five million cubic yards to the square mile. But this gravel 
is too much commingled with clay to make it available, in general, for 
ballasting or road-making, and with all this the county is not abundantly 
supplied with good gravel for such uses, well distributed in different 
localities. Enough has, however, been found to construct a system of 
free turnpikes not surpassed, in extent or excellence, by those of any 
county of similar size and situation in the State, although the material 
has had to be hauled, in some instances, for inconvenient distances. I 
