370 



NOTE ON GLACIAL CLAY. 



The pebbles and boulders were of all sorts of rocks, show- 

 ing that the beach from which they were moved was of large 

 area. 



The vein and trap rocks contributed a fair proportion 

 and the gneiss of the upper lands was represented, but there 

 were pebbles of two rocks not now known as local. These 

 will be determined later on. 



There were angular stones of various sizes in the gravel, 

 but they belonged to the rock which gave rise to the gravel 

 and were therefore in situ. 



The pit therefore consisted of (a) decomposed gneiss, red 

 in colour and without foliation and undisturbed ; (b) clay 

 which had been deposited with its contents from surface at a 

 distance. 



The rocks represented and the different sizes of the 

 pebbles indicated the carrying by some moving agent. 



The clay and its contents were deposited continuously 

 and from above. There was a complete absence of stratifica- 

 tion, hence the clays cannot have been water deposited from 

 streams. 



The appearances and the contents are consistent with the 

 deposition by floating or melting ice. 



I therefore tentatively associate the deposit with ice 

 movement, which would easily have collected and deposited 

 the clay and its contents. 



The flints are indefinite as to age and might be referred, 

 by different persons, to late Paleolithic or Early Neolithic 

 Age.* 



The deposit, being glacial, favours the opinion of the 

 flints being Paleolithic, and if this is confirmed it is practically 

 the first indication of Paleolithic man in Guernsey. 



The pebbles give undoubted proof of the prior existence 

 of a beach at a higher elevation than 300 feet. This has been 

 long suspected, but no satisfactory proof has previously been 

 met with. 



The points raised by this find are : — 



1. Man in Guernsey prior to the last local glaciation. 



2. Submergence to a greater depth than 300 feet 

 probably during glacial epoch. 



3. Movements of local ice caps. 



4. Evidences of great changes of climate. 



5. Total disappearance of the land surface which 

 contributed to the deposit. 



* The flints were examined in Oxford by Mr. ft. M. Marrett and Dr. Arthur 

 Evans. 



