642 GEOLOGY OF OHIO. 
This belt of building stone is of great importance to the eastern por- 
tion of the county. The Huron shale covers a large area and this is en- ~ 
tirely destitute of stone for ordinary uses. The margin only of the 
Waverly furnishes exposures for quarries, so that broad belts both east 
and west of this line depend mainly on this source of supply. Quarries 
of this horizon are quite extensively worked north of the county line in 
Harlem, Berkshire, and Trenton townships of Delaware county. The 
best known of these quarries are those located at Sunbury.. The Sun- 
bury stone is erroneously referred in Vol. I to a higher division of the 
Waverly, viz, the Berea Grit, but.it certainly belongs to the lowest of 
the sandstone courses of this formation, and can be traced without inter- 
ruption, from Sunbury to the points here named. Like the lower Waverly — 
generally, these beds are almost entirely non-fossiliferous. A few fu- 
coids are seen upon the surface of the layers, and the burrows of sea- 
worms are also sometimes found. 
(c) The Cleveland shale of Dr. Newberry, the Waverly black shale of 
Professor Andrews, as has been already stated, is known at but a single 
locality in the county, viz., at Haly’s Mills, in Jefferson township, on the 
banks of Rocky Fork. From ten to fifteen feet of this formation are 
here shown within the compass of an acre. The stone immediately un- 
derlying the black shale is quarried for local use, so that the line of 
junction is very distinctly seen at several points. The black shale lies 
upon the flat surface of the sandstone without the interposition of any 
other material whatever. A geological boundary cannot be more dis- 
tinct than this. The change is equally marked in other respects  Be- 
low this horizon, sandstones and shales, biue and black, are found for at 
least four hundred feet, representing periods of great length in their for- 
mation, and throughout them all, it is a very rare occurrence to find any 
trace of the life of the world in the ages to which these beds belong, but 
the moment that the Cleveland shale is reached, all this is changed. 
The beds are charged with ancient life, and that too, of the highest 
divisions of the animal kingdom, viz., vertebrates. The surfaces of many 
slabs are thickly covered with the teeth, and plates, and bones of the 
sharks and ganoids of this early day. Two brachiopods also, Lingula 
melie, Hall, and Discina Newberry, Hall, are abundant here, sometimes 
wholly covering the surface of the beds. The anomalous but very in- 
teresting fossils termed conodonés are found in great numbers, and in ex- 
quisite preservation in the shales of this locality. The best interpreta- 
tion of their structure seems now to be that they constitute the jaws of 
annelids. (See Silliman’s Journal, September, 1877, page 229.) 
The shale is heavily charged with bituminous matter. No analysis of 
