UNDERGROUND WATERS OF NORTH-WEST YORKSHIRE. 273 
The water from P 33 again comes to light at S 57, where it 
is joined by the waters of Long Churn Spring, which sink at 
P 42, about 100 yards to the west of S 57. 
The water from S 57 flows through a small gorge over a 
series of cascades and enters a cave at P 31. [PL XXXIII., 
Fig. 1.] This cave is the upper portion of a series of passages 
and chambers known by the general name of Long Churn, 
which has been carefully surveyed by members of the Committee 
with tlie aid of Mr. Theodore Ashley. [PI. XXVIII.] 
These passages are excavated in the upper portion of the 
Mountain Limestone, and are at no great depth from the surface. 
On entering at P 31 the cave is sufficiently high for a man to 
stand upright and a few yards from the entrance it divides 
into two. the one to the left being that followed by the water, 
the passage to the right being an " ox-bow " deserted by the 
stream except when in flood. About 50 feet below the point 
of reunion of the two branches, the stream plunges down a 
waterfall some 15 feet in height into a chamber measuring, 
roughly. 50 by 20 feet, the greatest dimension being at riglit 
angles to the general direction of the passage. The greater 
part of the floor of this chamber is occupied by a pool, from which 
the stream flows on in an easterly direction. At first the passage 
is low and one must walk in a stooping posture, and though 
narro\\- at the bottom it widens considerably towards the top. 
As we proceed the tunnel becomes more lofty, as the roof, which 
is formed by a massive bed of limestone, remains horizontal, 
but the floor gradually falls away. For the next 600 feet the 
character of the passage varies but little. There are. however, 
a few pools, varying from one to three feet in depth, and a number 
of deserted ox-bows, some of which are at a height of five or six 
feet above the bed of the stream. 
At the end of this 600-foot reach a small passage branches 
off to the right. This is some four feet above the water level 
and eventually rejoins the main passage lower down, though it 
becomes so low that it is not possible to get through. 
From this point the water flows for another 100 feet or so 
when the passage again bifurcates, the water in this case taking 
