A. Cave tn the Clinton Formation of Ohio. 2 
A CAVE IN THE CLINTON FORMATION OF OHIO. 
By Pror. JosepH F. James, M.Sc., U.S. Geo. SuRVEY. 
(Read May 6, 1890.) 
Tue Clinton formation as known in Ohio consists of a thin stra- 
tum of limestone, seldom attaining a greater thickness than fifteen 
feet. It is found fringing the outcrop of the Lower Silurian in 
Southwestern Ohio. The rock is more or less porous and liable to 
weather, and this, in addition to its limited extent, makes it of little 
use asa building stone.* The passage of this stratum his never 
been directly traced across the Ohio line into Indiana, and its pres- 
ence is not indicated in the Geolozical map of the State; at the 
same time in some of the counties near the border it has been 
noted. 
The porosity of the rock has rendered it liable to disintegration 
through the influence of percolating waters, and it is possible that 
had the formation attained a greater thickness in any locality, it 
would have been as prolific in subterranean cavities as the lower 
Carboniferous limestone of Kentucky. The hard blue limestone 
and the soft crumbling shales of the Cincinnati group are not fitted 
for the formation of caves in any portion of their extent. Conse- 
quently such a thing as a cave in any place in Southwestern Ohio 
where these strata are found, is unknown. In the Clinton group, 
however, there is found a cave of small extent, which I investigated 
a year or so ago, and as | believe no very full account of this has 
been published, a little space will be devoted to its consideration, 
The outcrop of the Clinton has not been satisfactorily traced in 
the field. Between the towns of Morning Sun and Camden, in 
Preble County, Ohio, the turnpike passes over an exposure, and 
as the wagons or buggies roll along, a hollow, rumbling sound is 
heard, as if the vehicles were passing over a bridge. This isa 
part of the cave, and though apparently of considerable extent, it 
is not possible to explore this portion because of the lack of any 

*In the Fourteenth Annual Report of the Geology of Indiana, for 1884, 
it is stated that (p. 51) this group has a thickness of twenty feet in Fayette 
County, and that it has been used in locks of canals, and as foundations for 
buildings. 
