446 GEOLOGY OF OHIO. 
southern boundary line to the vicinity of Rock Mills. To keep the con- 
tinuity of strata, as we proceed in our investigations, we shift the scene 
from Rattlesnake to Paint Creek. 
The next outcrop ascending this stream, above the striated rock in the 
vicinity of Smart’s Mill, in Ross county, is above the bed of the creek 
and one or two miles up stream from the last locality on the farm of Mr. 
Evan James. Here, we observe, a marked change has taken place in 
‘the lithological character of the bedded rock. I had no instrumental 
equipment which would enable me to ascertain whether or not this stone 
was conformable in dip with that of the last exposure. A eonsiderable 
- difference in altitude existed between the two exposures, but the inter- 
vening formations were not visible. The stone at James’ is a limestone, 
light in color, and fine grained, a good quality of stone for building pur- 
poses. The quarry was but little worked where the building stone had 
been procured, but ashort distance further up the stream, the strata near 
the creek are very thin, often not more than one-half an inch thick and 
none more than two inches thick, nearly white in color, and show finely 
gun and water cracks. These marks are delicate but distinct, and roughen 
the surface but little. They seem to have been formed on the beach of 
a, shallow, quiet water. The stone is fine in texture and soft to the touch. 
These strata are traced along the creek for about two miles, getting some- 
what thicker in the upper part of Rogers’ quarry. In no part of this 
distance were any organic remains discovered, but on the Washington 
and Greenfield turnpike, fifty or more feet highcr on the horizon and 
about west from the poins of first appearance of the bedded rock in the 
éreek, in the ditch by the road side, occur strata which show clearly 
marked indications of a lamellibranch mollusc less than a quarter of an 
inch in its longest messurement, also very distinct and beautiful fucoidal 
impressions. The fractures showed delicate markings of dendrites. This 
is perhaps the same stone which occurs weet of this locality at Mrs. Dos- 
ter’s on Walnut Creek, and has a local reputation as a fire-stone. 
Another and more massive exposure occurs two miles above Rogers’, 
a harder stone than any found below on Paint, and in some respects re- 
minded me of the Clinton. 
The locality of Rock Mills presents more points of interest to the geol- 
ogist than any other in Fayette county. Below is a section of all the 
strata visible in this vicinity. 
FEET 
- Yellow clay, seen on ridge east of the creek... ......-0-. 2-2 esses cee wne anne 5 
. Blue clay, hy es BO Gana COR Obdd o6diooad daotido bone 5 
Shale orslate, ‘* Soi ce aid aleialaha elute \tteldisia’w ata yetarala bd diahelees 10 
