cxxviii life of WILSON. 
from some unknown cause, the ground had been undermined, 
and had fallen in, in innumerable places, forming regular, 
funnel-shaped, concavities of all dimensions, from twenty feet 
in diameter, and six feet in depth, to five hundred by fifty, 
the surface or verdure generally unbroken. In some tracts 
the surface was entirely destitute of trees, and the eye was pre- 
sented with nothing but one general neighbourhood of these 
concavities, or, as they are usually called, sink-holes. At the 
centre, or bottom of some of these, openings had been made 
for water. In several places these holes had broken in, on the 
sides, and even middle of the road, to an unknown depth; pre- 
senting their grim mouths as if to swallow up the unwary tra- 
veller. At the bottom of one of those declivities, at least fifty 
feet below the general level, a large rivulet of pure water issu- 
ed at once from the mouth of a cave about twelve feet wide 
and seven high. A number of very singular sweet smelling 
lichens grew over the entrance, and a pewee had fixed her 
nest, like a little sentry-box, on a projecting shelf of the rock 
above the water. The height and dimensions of the cave con- 
tinued the same as far as I waded in, which might be thirty or 
forty yards, but the darkness became so great that I was forced 
to return. I observed numbers of small fish sporting about, 
and I doubt not but these abound even in its utmost subten-a- 
nean recesses. The whole of this country from Green to Red 
river, is hollowed out into these enormous caves, one of which, 
lately discovered in Warren county, about eight miles from 
the Dripping Spring, has been explored for upwards of six 
miles, extending under the bed of the Green river. The en- 
trance to these caves generally commences at the bottom of a 
sinkhole; and many of them are used by the inhabitants as cel- 
lars or spring-houses, having generally a spring or brook of 
clear water running through them. I descended into one of 
these belonging to a Mr. Wood, accompanied by the proprie- 
tor, who carried the light. At first the darkness was so intense 
that I could scarcely see a few feet beyond the circumference 
of the candle; but, after being in for five or six minutes, the 
