648 GEOLOGY OF OHIO. 
5. The Waverly shales of Ross county require no extended mention. 
They do not generally attain to the thickness which this division shows 
in Pike county, and on the western side of the county are considerably 
reduced. In the city of Chillicothe they measure 83.67 feet in thick- 
Ness. | 
They indicate ‘The same general history which the series elsewhere 
shows, their surface being covered with sea-weeds, sun-cracks, and rip- 
ple-marks. Where exposed on Stony Creek, in Franklin township, they 
afford the finest series of ripple-marks known in the Third Geological 
District. Similar exposures are shown in the same township, on the 
line of Indian Creek and its tributaries. 
In the report on Pike county a calcareous layer of remarkable com- 
pactness and evenness was noted as occurring near the base of the Wa- 
verly shales, and its composition, as shown by chemical analysis, was 
given. This same layer extends through all of the outcrop of this divi- 
sion in Ross county. In the vicinity of Frankfort considerable account 
is made of it as a building and flagging stone. Mr. Bergen, who made 
the examination of this part of the county, es that it be recog- 
nized as the Frankfort flag. | 
4. The Waverly quarry system continues to furnish in its notehweaee | 
extension a large supply of excellent building stone. ‘The character of 
the rock quarries agrees very closely in color, texture, and composition 
with the stone derived from the typical exposures; but a very much 
larger proportion of the series in Ross county is valueless than in the 
district below. The stone is quite frequently found in a peculiarly 
rough and ungainly condition, known among the quarrymen as “ turtle- 
back,” or “nigger-head.” In this state it has no possible uses, except as 
protection for river banks. In all of the central regions of the county 
the division is very much lighter than at Waverly and Jasper, being 
frequently found to measure five to ten feet only against thirty feet in 
the Pike county quarries. In Paxton and Buckskin townships there is 
a larger amount of stone again, but it is not found in as thick and valu- 
able courses as to the southward. 
5. Ascending in the scale, we next come to that interesting stratum, 
the Waverly black shale. No finer exposures of this are possible than 
are furnished in hundreds of sections through all of the central regions 
of the county, upon both sides of the Scioto River. The greatest thick- 
ness yet observed in this formation is found in Franklin township, near 
the mouth of Stony Creek, where it measures not less than twenty-seven 
feet. It is charged at this point with its characteristic fossils, Lingula 
melia and Discina Newberryi, and the remains of fishes, often in an excel- 
