THEE SONBIORV, SITALE OF (OfTLO 263 
HISTORICAL REVIEW. 
There have been different opinions regarding the age of the 
Sunbury shale, and mistakes in regard to its correlation between 
the northern and southern parts of the state, so that it is thought 
advisable to give a brief review of its literature. 
The shale was first recognized and named by Professor E. B. 
Andrews, in 1870, from outcrops in the Ohio valley in Adams 
and Scioto counties. He stated: 
There is a remarkable exception to the general character of the Waverly 
group, in a stratum of highly bituminous black slate, which is found about 137 
feet above the base. It is sixteen feet thick, and remarkably persistent in the 
Waverly, and is said by my associates to be found in the northern part of the 
SUALCm ices It contains the same mollusca, genera and species, as the black 
slate [Huron shale] viz., Lingula sub-spatulata M. & W., and Discina capax ? 
White. It also contains similar scales of small ganoid fishes. Besides these 
fishes there are remains of larger fishes.’ 
To this shale Professor Andrews gave the name of Waverly 
black slate, and reported that it ‘‘is evidently a very widespread 
stratum. It is not only found extending through the Waverly 
formation to the north, but it evidently accompanies the Waverly 
rocks in their dip under the Coal-measures.”’” 
In 1873, in describing the geology of Cuyahoga county, 
Dr. Newberry mentioned that the lower part of the Cuyahoga 
shale immediately overlying the Berea grit at Berea and Chagrin 
Falls contained ‘‘myriads of Lingula mele and Discina Newberryt. 
With these are a few scales of Pal@ontscus, a Carboniferous ganoid 
and teeth of Cladodus, a Carboniferous shark.’’3 
Under the description of Summit county occurs a similar 
statement, where it is reported that ‘‘at the base of the formation 
[ Cuyahoga shale |, however, immediately over the Berea grit, 
the Cuyahoga shale is sometimes crowded with millions of 
Lingula mele and Discina Newberryt.?+ 
In 1874, Dr. Newberry apparently correlated the Waverly 
*Geol. Surv. Ohio,“ Rept. of Progress in the Second District” [in 1869], 1870, 
p. 65. 
2 [bid., p. 66. 
3 Rept. Geol. Surv. Ohio, Vol. 1, Pt. I, pp. 185, 186. 4 Jbid., p. 212. 
