18^ FOSSIL REMAINS OF QUADRUPEDS, &C. 
plained on this principle. Though there is no apparent 
opening there for admitting the mud and animal remains, 
yet the seams between the beds of limestone may have been 
in some spots so open, as to allow the waters of the Deluge, 
in small quantity, to penetrate through them, before the 
rock was covered with alluvium ; especially as the strata 
might then be less compact than they are now. This water 
being loaded with mud and sand, mixed with animal re- ' 
mains, flowing backward and forward through the crevices, 
they were at length choaked up ; the mud filling up the in- 
terstices between the beds, where we now find it. The 
shifting of the water through these interstices, in a hori- 
zontal direction, may serve to account for the numerous, 
small, rounded, and apparently water-worn, cavities in the 
stone, occurring at the seams ; most of which cavities are 
filled with mud. The water might enter these horizontal 
seams, either at vertical cracks or clefts, or at some break 
in the strata, perhaps at that which formed the bed of the 
Wear, which flows past the front of Pallion Quarry. 
The rounded holes on the floor and sides of Kirkdale 
Cavern indicate, that water has also flowed through it for 
a considerable time, and with no small violence. If a flux 
and reflux continued here for some time after the bones 
were introduced, this would serve to break and wear them 
rapidly. The bones, or parts of bones, that are least worn, 
might be protected by having portions of fleshy matter ad- 
hering to them, or might be among the last that were drift*, 
ed in. I have some ends of leg-bones, or shank-bones, 
from the extreme parts of the cave, so rounded and worn 
as to resemble pebbles. I have also seen a few real pebbles 
from this cavern ; and sand is said to have been found in 
some of the farthest branches. In the Manor Vale Cavern, 
at Kirkby Moorside, Mr Bird found both sand, gravel, and 
decayed vegetable matter. But even the total absence oi 
