showed loose dry earth, some of it cemented by
drip from the roof until about as hard as lump chalk; then compact
clayey earth, also with travertine in small lumps; below this the
gravel and sand. The latter, at this point, seems to have been
deposited in the last stages of the formation of the cave.
Occasionally, along here, a small patch appeared that seemed to be
ashes; but none of it was more than 6 inches below the top of the
ground, and the substance may not have been ashes at all, but the fine
white limestone dust that wears off from the stone. There was nothing
in the trench, at any depth, after the chalcedony pebble, that could
possibly be due to human intervention, except these small patches of
ashes, if ashes they are.

At 165 feet from the entrance the cave made its fourth turn and
expanded into a chamber about 15 feet wide. Along the sides of this
and in the various crevices opening from it were great quantities of
clean ashes, plainly enough thrown there from fires made in the
central part. The gravel came to within 3 to 5 feet of the top, being
quite irregular. On the gravel was dry clay, seamed and fissured in
all directions so that it fell out under the pick in clods like
angular pebbles from an inch to 3 or 4 inches across. This was clearly
the result of muddy water settling in a hole and thoroughly
evaporating. There was also some travertine in small lumps here and
there through the clay, and above it was a mass fully 2 feet thick at
one side of the trench but running out before it reached the other
side. It was porous, almost spongy, and seemed to be the lime dust
from the roof and sides cemented by dripping water. Above all this, so
far as the trench extended toward the sides of the cave, was an inch
to 4 inches of loose, dry, dark earth, which on the left dipped down
to the clay, thus replacing the travertine.

[Illustration: FIG. 35.--Cross section of Fort Deposit Cave at 175
feet.]

[Illustration: FIG. 36.--Cross section of Fort Deposit Cave at 180
feet.]

At 175 feet the gravel had leveled down and was more or less mixed
with clay and sand. Above this was another "mudhole deposit" of clay
which had thoroughly dried out and become checked and cracked in all
directions. On the right this was covered with travertine slightly
mixed with earth and clay; on the left, above it and also at one place
within it, was a coarse gritty earth fallen from the roof but not
converted into a compact