476 ARCHEOLOGICAL INVESTIGATIONS—II [ELH, ANN. 44 
Along the east wall of this 7-foot cut the shale and clay held prac- 
tically the same thickness for about 6 feet, from which line they 
thinned somewhat toward the south. A slab slightly more than 4 
feet long and varying from 2 to 5 inches thick was reached at 8 
inches from the face at which the work was begun. It was in the 
blue clay, near the bottom; the presence of two small masses of clay 
under it and a depression or displacement of the shale beneath can 
best be explained by the supposition that in some manner it found 
lodgment in soft yielding mud lying on wet shale. This feature 
is shown in Figure 11, in which the depression in the shale is slightly 
exaggerated and all stones except the slab are omitted. An angular 
block containing about 6 cubic feet rested on the slab in such close 
contact that until loosened and forced apart they were supposed to be 
one rock. No other slab as large as this was found; but from the 
description given of the one which partially covered the skeleton, 
these two were very similar in size and shape. 
These data regarding the arrange- 
ment and character of shale and clay 
in chamber A will apply to the entire 
space between the sections shown in 
Figures 10 and 13. 
At 4 feet from the initial line of 
the work several large blocks which 
reached nearly across the cut had 
settled so compactly together that 
Fic. 11.—c. Large stone lying be- they seemed to form the face of a 
tween the loess and the shale : ~ 
ledge or minor cliff; but when un- 
covered they proved to be only detached fragments imbedded in the 
clay and resting on the shale. 
The removal of the 5-foot section on the eastern side brought to 
view somewhat different conditions. The surface of the shale in- 
clined toward the southeast to such an extent that it was only 5 
inches thick at the corner; the clay resting on it likewise became 
thinner in that direction, thus giving a considerable slope to its upper 
surface. The large slab above mentioned, as well as all other flat 
rocks except a few small ones, showed the same dip; also, they 
became less numerous until in the last 3 or 4 feet scarcely any were 
found. 
This dip of the shale toward the southeast seems to result from 
the action of running water which eroded the mass unequally. The 
thinning out toward the west, observed at the beginning of the 
excavation, on the opposite side of the tunnel, adds to the probability 
of this conjecture. The principal drainage line before the clay and 
loose rocks covered the shale was a few feet to the west of the present 
