Geology 



of yellowish sand one near the base, another near the 

 middle, and the third capping the higher portions of the 

 cliffs. Clearly the materials of the shingle could not 

 have been derived from these, and we had therefore to 

 look elsewhere for their source. In the meantime, 

 however, we made a further examination of the cliffs of 

 clay and sand, and one of the first things we noticed 

 about them was that both clay and sand contained 

 fossil shells. These were not wholly unlike the shells 

 which we saw on the sandy beach below the shingle, 

 and we made a collection of the fossils for purposes of 

 comparison. They included a cockle, an oyster, a 

 scallop shell, a whelk, and several limpets with curious 

 openings on the top resembling keyholes in form. On 

 comparing these with the shells on the beach, we found 

 that the oysters were precisely similar, but that the 

 cockle from the cliff was more elongated than the one 

 from the beach, and that the scallop and the whelk also 

 differed from the recent specimens, while the limpets 

 from the sand were without the " keyholes," being com- 

 pletely closed as regards their upper surfaces. 



On reference to our books we found that the fossil 

 forms belonged to the Pliocene formation, and we there- 

 fore concluded that the clays and sands of the cliffs were 

 of that age. 



Our map told us that some few miles to the east 

 there was a village called Clifftown, and on looking in 

 that direction we saw, by the aid of our field-glasses, 

 that the coast was high and rocky, and that the seas 

 were breaking far out from the shore in the neighbour- 

 hood of a headland which terminated in a bold vertical 

 cliff. 



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