igiO' M01.ONEY AND OTHERS. — A Blackwatev Cavern. 151 



Sheets of cracked mud occupied the floor. Under the south 

 wall of the gallery was a horizontal fissure, through which the 

 water had apparently vanished. The highest level at which, 

 the water ever stands is about 4 J feet. This is plainly marked 

 on the side walls. This pool may be in siphonic communica- 

 tion with the River Blackwater, which flows at a distance of 

 about 100 yards from the cave's mouth, but then there was no 

 noticeable change in the level of the river during the 24 hours 

 to account for this remarkable disappearance of a sheet of 

 water 2J feet deep. Moreover, the water was clean cave- 

 water, and did not look like the brown overflow which would 

 be brought in from the Blackv/ater. Another difficulty sug- 

 gests itself If this be an overflow channel it should surely 

 rise to a height greater than \\ feet when the heavy winter 

 floods bring down the drainage of one of the wettest counties 

 in Ireland. A light could be thrown on the subject by a 

 comparison with the temperature of the Blackwater, and by 

 taking a series of levels at the points where water occurs in 

 this and in the other caves along the clifi". Mr. F. W. Clare 

 informed one of the party that with a companion he descended 

 into a deep muddy passage in one of these caves, along which 

 they travelled until they heard the rush of a river over stones 

 and shingle. The}^ imagined it was the Blackwater flowing 

 overhead ! There are cases of subterranean streams flowinor 

 in siphons under large rivers, but it is difficult to believe that 

 there could be a dry channel under the Blackwater, especiall}- 

 in a cave containing water on a higher level. Local tradition 

 alleges that there is a passage under the river, but, then, local 

 tradition in the case of caverns is almost invariablj^ wide of 

 the truth. The taking of levels, however, might show that 

 not only the pool chamber but the north end of the " Cloisters " 

 are below the level of the river. The ''Cloisters" seem to 

 run under the space between the cliffs and the river bank. 



Mr. John Fitzgerald, the owner's son, accompanied the 

 party through and assisted them in their explorations. 



