Deposits, Limestone Creek. 7 
percolation of acid-laden waters from tlie interior — i.e., as the 
main channels became choked up by the accumulation of 
ddbris, silt, and gravels, etc., the rushing waters caused by an 
annual flood would endeavour to find a passage along the 
lines of joint or shrinkage. At present the water traverses 
from A to B (see plan), and from B finds its way 
through narrow or flattened orifices to lower levels, re- 
entering the Limestone Creek about 200 yards below 
the entrance to the cave. The I’oof of the entrance, and for 
some distance inward (about 20 feet), consists of a mass of 
whitish marble beautifully scalloped by the action of running 
water. The entrance is very nearly on a level with the 
Limestone Creek, from which it is distant about 70 feet, 
and separated by the alluvium and an accumulation of 
debris (see plan). After the first 88 feet are traversed 
the narrow entrance passage gives place to a large chamber, 
from which start various ramifying passages. Those through 
which the water runs are narrower than that which I have 
shown traverse lines. The floors of 2 to 8, 4 to 5, and 7 to 
8 are simply masses of soft and hardening silt with, in some 
places, stalagmital covering. These present many favour- 
able spots for fossil hunting, but owing to the limited time 
at my disposal I could not undertake any examination. 
However, the plans and sections submitted may prove useful 
as a basis for further examination by any one disposed 
to undertake such interesting work. Many of the roof 
fissures extend almost up to the surface of the deposits, 
quite 60 feet in some places, and their sides are frequently 
covered with stalactical drapery of every conceivable shape 
and of very beautiful appearance. The rate of accumulation 
of these stalactites depends, apparently, on two principal 
causes — viz., the quantity of percolating water holding car- 
bonate of lime in solution, and the rate of evaporation of the 
carbonic acid from the surface of each drop of water, the 
latter depending upon the temperature, accessibility of the 
air, and other conditions. During my last visit to Pender- 
gast’s Cave, No. 1 (there had previously been a rather heavy 
rainfall), the stalactites were covered at their extremities 
with bright, clear drops of water, some indeed were dripping, 
and there was also a visible increase in the quantity of 
matter I have denominated calcareous froth. It is probable, 
therefore, that the rate of stalactital growth depends largely 
on the seasons, a wet season being most favourable. The 
lines of bedding are well seen in the interior of the cave, 
