286 UXDERGROUXD WATERS OF NORTH-WEST YORKSHIRE. 
stream sinks at P 94. These two streams unite below the 
Washfold. 
The main joints at this point run X. 10° W., while the 
secondary series points X. 40° E. 
The water takes the line of the former by way of Little 
Douk Cave to Douk Cave P 95. 
Douk Cave is a deep ellipsoidal hollow with vertical walls 
round the greater part, the longer axis running approximately 
E. and W. [PI. XXXVII.]. 
The bottom of this liollow consists of large faUen blocks 
and the hole i:)robably owes its origin to the falling in of the roof 
of a large subterranean chamber. 
At the eastern extremity of the hollow is a low cave from 
the mouth of which a waterfall discharges the stream from 
P 94 and P 96. 
The cave has been traced for a considerable distance 
passing below Little Douk Cave, which is a vertical shaft open- 
ing into the roof of the passage. 
Fluorescein was introduced at P 94 on June 30th at 2.30 
p.m., and the colour was observed in tlie waterfall at Douk Cave 
at 3.50 the same afternoon. 
Below the waterfall the stream passes down a series of 
cascades to the western end of the hole, where it sinks among 
the loose blocks of limestone mentioned above. The fluorescein 
was again observed in Chapel Beck, in the pool below God's 
Bridge. S 112, at 1 p.m. on July 3rd, and was much stronger 
at 2.30 p.m. 
The stream was low at the time, and there was little water 
above God's Bridge. Weathercote Cave P 88 and Hurtle Pot 
P 90 were carefully watched from June 30th to July 3rd, but 
no trace of the colour was to be seen in eitlfer. 
The conclusion arrived at was, therefore, that the water 
from Douk Cave joins Chapel Beck on some part of its under- 
ground journey between Hurtle Pot and God's Bridge. 
The main joint at Douk Cave runs N. 65° W., and this, if 
continued, would strike Chapel Beck in the neighbourhood of 
the Vicarage, which agrees very well with the conclusion men- 
tioned above. The secondary joints are X. 45^ W. and X. 15^ W. 
