BUILDING STONE. 609 
opposite shore. These beds are overlaid by 250 feet of shales, which 
are called by Professor Orton the ‘‘ Eden shales”; and these in turn 
are overlaid by the so-called “ Hill Quarry” beds of limestones, from 
which most of the stone used in the county is derived. 
Six quarries of importance are at present in operation at Cincinnati 
with exposures of from 40 to 75 feet, of which some 10 to 25 feet is dis- 
_ tributed throughout the section in layers from 1 inch to 10 inches in 
thickness. Slabs 6 feet long and 6 feet wide can be extracted. 
The li.ce which is burned from the stones of the Cincinnati group is 
dark and unfit for plastering, but for foundations, ete., it is of especial 
value, as it possesses some hydraulic capacity. Specifications for cellar 
walls, bridge abutments, etc., in this region always call for Cincinnati 
lime. 
Itis thus seen that the stone is interstratified with beds ofshale, which 
forms from one-fourth to one-third of the whole section. In other parts 
of the series the proportion of stone falls to one-tenth of the thickness. 
of the section, the main mass being composed of shale or clay. The stone 
seldom exists in such condition as to make a building stone that can be 
used in fronts, and it is mainly employed for rough construction, although 
some of the churches in Cincinnati have been built from it. 
As the dip of the blue-limestone beds is mainly to the north, while 
the direction of the Ohio valley at Cincinnati is toward the south, by 
proceeding up the river layers of the formation are brought to the sur- 
face that are lower than any occurring in the river quarries of the city. 
The Point Pleasant quarries, in Clermont county, are consequently 
situated in a different and lower level, and Professor Orton states that 
this section furnishes the most desirable building stone of the blue-lime- 
stone series. It dresses more easily and possesses a better shade of color, 
combined with a general exemption from the weathered seams that dis- 
figure the higher beds. The quarries are situated at the water’s edge, and 
river transportation enables the stone to be brought to the city easily. 
In a church on the corner of Kighth and Elm streets, Cincinnati, the ap- 
pearance of the stone can be seen to the best advantage. As the demand 
for the stone is local, the annual production fluctuates between wide 
limits, and the value of the product has sometimes fallen very low. 
There is quite a large number of small quarries in the neighborhood, 
each producing from $200 to $300 worth of stone annually. 
39 G. 
