CAE OWYN CAVE, NORTH WALES. 571 



Dr. Geikie visited the cavern at the request of Prof. Hughes and 

 myself on October 10th, Messrs. Hughes, Luxraoore, Morgan, De 

 Ranee, and Hilton Price being also present. Unfortunately I was 

 unable to be there. Subsequently Dr. Geikie kindly furnished us 

 with the following report : — 



" The question on which my opinion was asked with reference to 

 this cave was, I understand, the following : — whether the glacial 

 beds lie undisturbed upon the bone-earth at the end of the cave, or 

 whether their present position is due to the fall of the roof or wall 

 of the cave, and their consequent descent upon the cavern floor. 

 Accordingly I visited the cave on the 10th instant and examined 

 the section laid open in the pit that was dug in the glacial deposits. 

 The conclusions I formed may be thus summarized : — 



" 1. The bone-earth projects beyond the present limits of the 

 cave, but it probably never did so originally; hence I have no 

 doubt that the roof or wall of the cavern has given way. The large 

 masses of limestone lying at the bottom of the pit no doubt repre- 

 sent a portion of the fallen material. 



" 2. These fallen blocks lie on the bone-earth. The material 

 resting upon them has, of course, been removed in the excavation 

 of the pit ; but I observed that the block nearest the northern wall 

 of the pit passed under the base of the undisturbed glacial beds. 



"3. Against the lower part of the face of limestone on the 

 northern side of the pit there is undoubted evidence of slipping, the 

 lower layers of pebbly sand and clay being vertical against the 

 wall of rock. This disturbance, however, I could trace only a few 

 inches outward from the rock-boundary. It does not affect the 

 main mass of glacial deposits, and is referable, I think, to solution 

 of the limestone along its outer surface. The various layers of 

 glacial sands and clays were traced by me continuously across the 

 pit. I could see no evidence that they had ever subsided into a 

 cavity caused by the fall of the limestone into the cavern. 



" 4. Prom the data presented by the pit-section I would infer 

 that the fall of the roof or wall of the cave took place before the 

 deposition of the glacial deposits, and that during a period of sub- 

 sidence these marine strata were subsequently laid down against 

 the limestone-bank so as to conceal this entrance to the cavern." 



Mr. Morton also visited the section, and has kindly sent me the 

 following note giving the results of his observations in June and 

 October : — 



" In June last, during the progress of the excavation in front of 

 the original entrance to Cae Gwyu Cave, I stayed at the inn close 

 by for eleven days, besides visiting it on other occasions before and 

 since. During that time I had, of course, ample opportunity of 

 constantly observing the Boulder-clay, as well as the sand and 

 gravel, and other beds beneath it. Prom the first time I saw the 

 section I felt convinced that all the beds were strictly in situ. The 

 bone-earth had evidently been disturbed, and a stalagmitic floor 

 broken up, and the fragments, often large blocks, mixed up in it. 

 The laminated clay had evidently been tranquilly deposited over it. 



