1853.] 



TRIMMER ON A GRAVEL ON CLEVEDON DOWN. 



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stone ; but with them are associated 

 other fragments, which appear refer- 

 able to formations foreign to the ridge 

 on which the gravel rests. 



A few specimens, collected hastily 

 the evening before I left Clevedon, ac- 

 company this paper. They are sub- 

 mitted to the examination of those 

 geologists who are better acquainted 

 with the rocks of this neighbourhood 

 than I am. 



Neither pebbles of granite nor ma- 

 rine shells having yet been found in 

 this gravel, it cannot be absolutely 

 identified with the erratic tertiaries. 

 There is no sera, however, to which it 

 can be referred with so much proba- 

 bility as the Pleistocene ; because there 

 is no other during which we have 

 evidence of the transportation of de- 

 tritus over great inequalities of sur- 

 face, and the Walton and Clevedon 

 ridges acquired their present insulated 

 character at an epoch so remote as 

 the Permian, as is evident from the 

 Magnesian Conglomerate which sur- 

 rounds them. 



Postscrijit. — It has been suggested 

 by those whose opinions are entitled 

 to great weight, that the Clevedon 

 pebble-bed is a conglomerate of the 

 Permian ajra. 



I am compelled to dissent from 

 these views for two reasons — its posi- 

 tion with respect to the undoubted 

 Permian strata, and difference of li- 

 thological character. "With respect to 

 position, I have already discussed that 

 point, and shall only add the accom- 

 panying diagram by way of illustra- 

 tion, constructed from the Govern- 

 ment Geological Map (see fig.)- 



With respect to lithological cha- 

 racter, the Permian rocks of the 

 neighbourhood of Clevedon should 

 rather be called magnesian limestone 

 than conglomerate. They consist of 

 a limestone, fine-grained enough to be 

 sculptured into architectural orna- 



