296 The American Geologist. ^^^^ 19°=^- 
I), with sketches and descriptions, as g^iven below; excavations 
were made into the terrace and pseudo-terraces below the 
house, and into the loess at points south from the house, up the 
little tributary creek. Several samples were secured for mi- 
croscopical examination. 
The walls of the tiimicl. 
The floor of the tunnel dips toward the north or northeast, 
about one foot in thirty feet. Hence the floor of the entrance 
is about two feet lower than the floor at the further end of the 
tunnel. 
Station A. The first examination was made at the entrance. 
The difl'erent parts of the material penetrated by the tunnel are 
numbered as heretofore. The diagram seen in Fig. i, Plate 
XVH, illustrates the structure at the entrance, drawn to a 
scale. It has the following description. 
No. I is divisible into la and ib, the former at the bottom. No. la 
is twelve to fourteen inches thick, composed of angular debris of Car- 
boniferous limestone and shale, not much rotted, but mingled with 
finer materials of loess-like color and appearance. No northern drift 
seen ; not geest. The surface of the limerock is a little below the floor. 
No. lb, about two feet thick, is more sandy and loam-like, contain- 
ing loess-kindchen and pieces of limestone. In the upper ten inches, 
and faintly in the lower portion, are indistinct signs of horizontal as- 
sortment or structure. Some limestone pieces are four to six inches 
in diameter. 
No. 4 is a distinct silt stratum, two and one-half inches in thickness, 
and runs over the foregoing intact to the very door of the tunnel, with 
disturl)ance of continuity only at the very northern end where late 
weathering may have worn it off. The transition above and below 
No. 4 is sharp and sudden, as evidenced l)y the change of color, texture 
and evident composition. 
No. 2. extending to the roof, shows here no noteworthy feature^ 
having the aspect of ordinary loess. Its microscopic characters have 
already liecn given. 
Station B. The next examination was made at sixteen feet 
from the entrance. At this place the tunnel 's enlarged two 
and one-half feet in each direction, causing a rectangular 
shoulder in the wall. The diagram shown in fig. 2, plate 
XVII, consists of two parts. That on the right represents the 
sliotilder in the west wall, facing south. The remainder shows 
the continuation of the west wall of the tunnel. 
In the south-facing shoulder the layer No. 4 is seen to thin out to a 
point and disappear in No. 2, at the same time rising slightly toward 
the west, and not perceptibly toward the south. 
