153 
has probably, by a revulsive action, bared their bases by washing back 
to a distance of two or three feet previously-deposited loose grit. 
The slope under the parts of the above rocky stacks now under- 
going decay, is too slight for rain to carry the decomposed grit or sand 
away. The rain sinks into the sand, and remains till it is evaporated. 
The bottom of the valley at the base of the slope, and within a few 
yards of the lower stacks, consists of clay, with rounded stones in its 
upper part at least. The absence of a section of the clay prevented my 
seeing whether it was argillaceous shale in situ, or a boulder drift {see 
plate, fig. 14). In either case, the bottom of the valley ought to be 
covered with sand according to the subaerial or " wash of rain " theory 
of the denudation of the rocky stacks. The rocks, now missing, by 
which these stacks were once joined together, would appear to have 
been swept clean away, with the exception of a little loose grit and 
sand. On the field around the unscathed rocks, rounded pebbles (as 
before stated), may here and there be found attesting the marine nature 
of the denudation by which the rocks were left. 
In a quarry to the north of the above rocks, the line of demarcation 
between the hard gritstone and the coarse sand and detritus above, is 
so sharply defined as to show that the latter is not a disintegration in 
situ, but a local drift. 
GOREDALE. 
The entrance to Goredale is a large irregular cove bounded on each 
side by terraced slopes, and terminated behind by a wall of limestone 
rock, hollowed out into a smaller cove, which is breached at its inner 
end by a very narrow goi-ge. The reddish-brown clay of the plain of 
Craven, with a few sandstone mixed with numerous limestone boulders 
arid pebbles (some of the latter scratched and striated all round), rises 
up on each side of the entrance to Goredale, covers the bottom of the 
valley, underlies the brook, and runs up as far at least as the mouth of 
the smaller or inner cove, whe^e it is replaced by numerous angular 
blocks. The inner cove is bounded on three sides by a continuous wall of 
rock, except where the brook makes its entrance in the form of several 
cascades. A part of the cliflF on the right-hand overhangs its base at an 
angle of at least 20 degrees from the perpendicular. Near its summit 
there is a noticeable pothole or smooth concavity. The inner and upper 
part of the rock on the left likewise overhangs. Its face is indented by a 
rough horizontal groove about half-way up, and a smooth groove near 
the top — both, I believe, the work of the sea. The height of the cliffs 
has been exaggerated. On the right-hand side the overhanging cliflf 
rises above its base to a height of about 130 feet at one part, and 160 
feet farther on. The cliff on the left is about 160 feet high, but the 
lower part, immediately above the stream, projects in the form of a 
