ON THE EXPLORATION OF THE SETTLE CAVES. 135 
tocene fauna at some depth below the laminated clay, they never having been 
found above it. Next, the exploration brought to light the existence of a 
bed of glacial boulders resting on the denuded edges of the lower cave-earth. 
The work of the past year has shown exceedingly well the extent and im- 
portance of this bed, and further has brought to light the existence of several 
well-glaciated small boulders in the laminated clay itself. This clay, so far, 
has yielded no organic remains. It ranges quite across the cave, and is co- 
extensive with the explorations so far as they have gone, and in one place 
attains a thickness of 12 feet. It has been a horizon of great importance 
from its continuity, distinguishing the earlier from the later beds. The latest 
work in chamber D (on the right), however, appears to show that it is di- 
minishing in thickness as we go inwards in that direction. Besides the main 
bed of it, many of the little chinks between fragments of rock in the lower 
cave-earth have been filled up with it. This filling in may have occurred at 
about the same time as the formation of the great mass above; for certainly 
glacial conditions imply amongst other things the running of much muddy 
water, and wherever preexisting chinks occurred, they would have much 
chance of being filled up. Laminated clay of course may be, and often is, 
formed under other than glacial conditions (that of the Victoria Cave, indeed, 
bears a strong resemblance to the famous Nile-mud); but here its thickness and 
the contrast it affords to the deposits above and below, taken with its extent, 
seem to demonstrate a change and a long continuance of distinct physical 
conditions, 
It was noticed by those who visited the Victoria Cave last year that it is 
approached by a narrow cutting on the right as you face it. This had been 
imade through a great thickness of “screes” or limestone talus ; and below that 
talus, close to a large fallen block of limestone, which, with the face of rock 
on the right, formed a natural arch about 7 feet high, were visible at that 
time a few glaciated boulders. It was determined to expose these boulders 
and follow them, noting their position and range; but, in order to do this, 
we were under the necessity of removing a great mass of talus. Moreover, 
the “tip” of the old workings had accumulated in the front to such an extent 
as to seriously impede the operations. We therefore proceeded to remove a 
large breadth both of the tip and of the talus. The removal of the tip was 
of course mere mechanical labour, but the talus was removed with careful 
searching for the following reasons. 
In the first place, it occurred to us that if the boulders beneath the cliff 
had fallen from that cliff, or from hollows in it, it was not improbable that 
other boulders might be found at different heights in the talus. 
Secondly, we thought that if the boulders at the bottom of the talus had 
been deposited in their position in glacial times, and the talus represented 
the wearing away of the cliff by frost and other atmospheric influences, we 
might get a succession (an imperfect one, but still a succession) of the differ- 
eut forms of life which had followed one another through that long period. 
Our first inquiry established the fact that through this great thickness 
(19 feet) of talus, from the base of the Roman layer which lies within the 
first two feet of the surface down to the horizon where the boulders lie in a 
great mass, not a single fragment of foreign rock, whether of Silurian grit, 
of Millstone-grit, or of limestone, other than that of which the cliff above is 
composed, occurred. The whole mass consisted of sharply angular fragments 
of white limestone. No rounded forms existed; nothing with any of the. 
characteristics of ice-worn boulders or of stream-borne pebbles. The whole 
deposit spoke of the slow wearing away of a cliff, free. from drift, by the 
