STATE GEOLOGIST. 91 
are dark blue in color, frequently full of globular flint or chert, and very 
fossiliferous. They are seldom magnesian, but would make a dark 
cement on account of the carbonate of iron which they usually carry. In 
a few localities, these stones swell up to workable proportions. One of 
these is at a point about two miles southeast of Flint Ridge, in Licking 
county, Ohio, where a 12-foot ledge of favorable composition is visible 
and could be easily quarried.. Another at Somerset, Perry county, 5 
feet thick is of the same character. The composition of these stones 
shows, after careful sampling, as follows: 
Per Cent. 
Licking. | Perry. 
Sill Cae Ree UP oe Liane UR e 2 oe 44.54) 31.70 
PAC UIT AOR UAC peers cep nuctae at (ea dane oe hy 6.78 2.91 
Merri CroxiGl enue wiie eiane oni teta lime ailing ss 2.20 iL 
CAP NOME Cr CMON cocooce ds cones bboeoue 43.18 61.75 
Carbonaberolpmacneslagac aca ya er ana 1.09 0.83 
97.79 78.74 
These would make very desirable stones for mixture with a purer 
stone, as a means of introducing the necessary silica and alumina. 
In the southern part of the State, in Scioto county, on the edge of 
the territory of the Ferriferous limestone, the Mercer stone undergoes a 
local thickening at Howard furnace, making a promising material at 
that point as shown by the following analysis: 
Per Cents. 
SC aire sree: Bote e geet ae Myriam MTR a ouN GOR oy Waurha ay na ia alas LOZ 
PANLUTI IIA eer Meanie Nc hon eum MI GAE aia a Ce at cat Ta 0.62 
HEE CRO Gem panei dyna tae Mes CRC RENN A MONI SL EE atc 1.08 
Carbonaberom Cal cium ane tsi ee ano ea eaicee ne has aan 94.85 
Canbonaterotmacnesiumbesy. sete aie ole mianemiety sacl ORO 
98.48 
As a rule, however, the Mercer stones are too thin and often too 
cherty to be considered as a possible asset for a cement industry. 
Putnam Hill.—The next is the Putnam Hill limestone in central 
Ohio and the nearly equivalent Ferriferous limestone found in north- 
eastern and southern Ohio. The area occupied by the two does not 
overlap, at least has not been shown to do so to any important extent, and at 
the point where one begins the other is usually dwindled down to a mere 
trace. Both stones lie close below the lower Kittanning or No. V coal, 
but they are probably stratigraphically distinct. The works of the Dia-— 
mond Portland Cement Co., at Middlebranch, Stark county, O., are sup- 
