downward finds some obstruction to its free passage out at the bottom
of the chasm.

The only safe plan of excavation seems to require the removal of all
the earth between the side walls to a depth below the mud. If the rock
bottom, or any solid bottom, is at a depth of 120 feet, there is small
chance that man lived in this region at a time when it was easily
accessible.

SALTPETER CAVE.--This is about 600 yards northwest of Wyandotte Cave.
"The entrance, in a side of a ravine, is 5 feet high and 19 feet wide.
Once within, a gigantic room expands, 220 feet long, 75 feet wide, and
10 to 30 feet in height, with smooth flat ceiling and earthen floor,
the latter descending and with its edges much encumbered with fallen
rock." [W.S. Blatchley.]

From the description given, this would seem an ideal site for
research. Unfortunately, the bottom of the ravine is not more than 5
feet lower than the top of the talus at the entrance. This slight
elevation is the only barrier which keeps the surface water from
flowing in, and while the ravine seldom has any water in it, there
would be enough after a moderate rain to drown out the diggers who
were working below its level if the bank were removed.

LITTLE WYANDOTTE.--This, like three caves on Blue River above
Wyandotte, four in the vicinity of Leavenworth, and one on the
opposite side of the river in Meade County, Ky., has a small entrance
in solid rock, with a steep and narrow passage to the foot of a slope
which does not expand into a room of any size until at some distance
beyond daylight.

HARRISON COUNTY

The only cave of any note in Harrison County is at the King quarries,
5 miles east of Corydon. It has two outlets, one at the foot of a
little cliff, through which a fine spring has an exit; the other in
the face of the cliff, about 10 feet higher and a little to one side.
The latter discharges more or less water after every rain. The
drainage of several large sink holes is through the two openings. The
owner says mud has accumulated to a depth of 3 feet on the floor
within his remembrance, due to cultivation around the sink holes,
which causes the soil to waste.

* * *

ILLINOIS

MONROE COUNTY

MAMMOTH CAVE.--The so-called "Mammoth Cave of Illinois" is near
Burksville, in Monroe County. An opportunity was afforded to visit it
while engaged in the cave work. It is very extensive, according to the
owner's description, being "7 or 8 mi