192 . Proceedings of the Royal Irish Academy. 



This pot-hole consists of a vertical shaft 30 feet deep, at the bottom of 

 which is a ledge at the top of the boulder slope in the great chamber. 

 In our exploration, 1908, we entered the cave from this point first; from 

 the ledge a scramble through the boulders brought us to the top of the 

 vertical climb above the Pool Chamber passage, and from there the rest 

 of the cave was explored. 



On our return, while the rest of the party were clambering through the 

 boulders towards the foot of the ladder, two members, who were exploring 

 the chamber, noticed a glimmer of light in one corner ; this proved to come 

 from the bottom of pot-hole E, which is an oblong comparatively shallow 

 boulder-filled depression full of trees and ferns, A few minutes' work 

 sufficed to clear a way through the stones which obstructed the opening, 

 thus laying clear an entrance to the cave which had never been suspected. 



As a result of this last discovery, there is now no danger, and only 

 comparatively little difficulty, if due care is exercised, in visiting any portion 

 of this fine cave ; it will, however, probably never become a show-cave, as the 

 climb from the foot of the Great Boulder Chamber to the end of the 

 Pool Chamber Passage is one not to be rashly undertaken. It is to be 

 hoped that any future visitor will be careful not to damage any of the 

 stalactites, as has been done in so many of the better-known caves. 



A well-known passage leads from the floor of this pot-hole (E) to the 

 entrance above the water- tunnel in C/ so that now a complete circuit is 

 possible from one opening in the floor of pot-hole E to the new opening, 

 which is within 15 feet of the old one. It is interesting to note that, on 

 working out the survey, as made by our party, we had made an error of 

 only 20 feet in the position of these two openings, which formed respectively 

 the commencement and the conclusion of the underground survey — a result 

 which indicates that the rest of the plan is fairly accurate. 



In order to test the accuracy of the report that the Monastir stream 

 emerged at Marble Arch, half a pound of fluorescein was introduced into 

 the Monastir stream at 11.30 a.m. in dry weather : this was clearly visible 

 in the upper Cradle Hole Cave at 10.45 a.m. the following day, and at 6.45 

 the same evening, it began to emerge at the Marble Arch spring, having 

 taken thirty-one hours to travel a distance of slightly more than half 



a mile. 



Bibliography. 



E. A. Martel : Irlande et Cavernes Anglaises. Paris, 1897, pp. 19-45. 

 H. Lyster Jameson : On the Exploration of the Caves of Enniskillen for 

 the P.I A. Flora and Fauna Committee. Irish Naturalist, vol. v., p. 93, 1896. 



1 Another branch of this passage leads down to the lake between D and C. 



