10 PKOFESSOR T. MCKENNY HUGHES, M.A. 



lowlands. Underground passages, high above the present 

 water-channels, were swept clean by the body of water forced 

 through them under enormous pressure. Caves that had 

 been sealed up for years with barriers of stalagmite, which 

 one would have thought might have defied the rush of any 

 flood, were burst open. Most of this debris all, in fact, 

 that was moved by the first rush of water was carried down 

 the valley. Some remained around the mouth, and some in 

 embayed corners in the caves. Here we saw fragments of 

 stalagmitic floors, mixed up with debris washed in from the 

 swallow-holes above. Some might have seen here evidence 

 that, after the cave had been formed and occupied and 

 gently filled by earth and coated and partitioned by stalactite 

 and stalagmite, there came an age of flood perhaps of 

 submergence when the old deposits were re-sorted, the old 

 floors broken up, and that the cave then entered upon 

 another phase of its history. How different the facts ! I 

 saw this revolution taking place. It was all over in three 

 short hours. It was another illustration of the great law of 

 Uniformitarianism, which I have heard the Duke of Argyll 

 well state thus : Local catastrophic action is not inconsistent 

 with continuity of causation. 



We must bear these things in mind when we are examining 

 cave-deposits. 



The peat torn away from the mountain-side above was so 

 beaten up in this great natural churn that the water of the 

 tarn did not get clear for months. The sediment did not 

 settle for three weeks in a long glass which I filled during 

 the flood. There must have been a layer of fine carbonaceous 

 clay formed over the bottom of the tarn and in many a 

 deep cave-pool after that storm. When the rain ceased, the 

 water soon ran off the mountain-side, and I went up to 

 examine Gaping Gill, the great swallow-hole that feeds the 

 cave. I found a passage opened out among some blocks on 

 one side of the stream a little above the chasm. I thought I 

 might perhaps find a zigzag descent, which would lead me 

 down into Gaping Gill Hole. So I crept in. 



I soon got beyond the light, and therefore took the pre- 

 caution of throwing stones in front of me before I advanced. 

 I found the slope increased rapidly, and then all of a sudden 

 the stones dropped into a deep hole, down which they 

 whirred, knocking the sides here and there till they dropped, 

 with a booming noise, into deep water below. I wriggled 

 out, and returned another day, with friends and candles and 

 string, for I could not drop the stones straight so as to clear 

 the sides, and so estimate the depth by the time they took in 



