562 



BR. H. KICKS ON THE 



cliff over another entrance to the cavern. Before it was known that 

 this so-called chamber was the widening of the cavern towards the 

 new entrance, the following dimensions were sent to me by Mr. 

 Lnxmoore: — passage leading to chamber, height 6 feet 6 inches, width 

 6 feet ; sup^DOsed chamber, height 9 feet, width 9 feet 6 inches, 

 length 11 feet 3 inches. The deposits in the chamber were an 

 increased thickness of the bone-earth, with imbedded blocks of 

 limestone, as in the passage leading to it and in other parts of the 

 cavern, laminated clay, continuous with that found in the passage, 

 and upon the latter stratified marine sands and gravels. The 

 section, it was stated, was perfectly clear, and all the deposits 

 could be traced right across the so-called chamber. The cavern 

 was visited by Prof. Boyd Dawkins in September, and in a 

 letter he wrote to me on December 11, 1885, the following passage 

 occurs : — " I have carefully compared the sand and gravel found 

 in the upper cave (Cae GrwjTi), and sand sometimes adherent to the 

 bones, with the glacial sand and gravel which occurs in the valley a 

 little way above, and find that in every particular they agree. I have 

 also compared them with the glacial sands and gravels near Bryn 

 Asaph and find that all three are composed in the main of quartz, 

 quartzites, and Silurian fragments." Up to this time, and for some 

 months after the work was suspended, the surface of the field re- 

 mained perfectly even, and there were no indications of any sinking 

 of the ground. During the winter months, however, after a heavy 

 fall of snow, some of the materials slipped inwards into the so-called 

 chamber, and the surface of the field over the spot gradually sank. 



Eesearches in 1886. 



Por the purpose of continuing the researches in 1886 a grant was 

 obtained from the British Association for the Advancement of Science, 

 and the following Committee was appointed, viz.: — Prof.T.M^^Kenny 

 Hughes, Dr. H. Hicks, Dr. H. Woodward, and llessrs. C. B. Lux- 

 moore, P. P. Pennant, and Edwin Morgan. 



Work was resumed during the last week in May under the super- 

 intendence of Messrs. Luxmoore, Pennant, and Morgan, and I joined 

 them a few days later. It was thought advisable to sink a shaft 

 from the surface of the field, over the depressed part, so as to uncover 

 the supposed chamber. Much to our surprise, after a few days' work, 

 we found that what had appeared from within the cavern to be a 

 broken roof, or line of fissure, was the abrupt termination of the 

 limestone in a cliff with an opening below into the cavern. Further 

 researches revealed the fact that this opening was a wide entrance, 

 over 11 feet across and with a height of from 6 to 8 feet. As the shaft 

 was only about five feet across at the bottom at this time, a perfectly 

 clear section of the deposits as they extended into the cavern could 

 be seen, and the particulars now shown in fig. 1 were then carefully 

 noted. Mr. C. E. De Eance, F.G.S., of the Geological Survey, was 

 at that time in the neighbourhood and, at my request, visited the 

 cavern and kindly assisted us in taking correct measurements in the 



