62 GEOLOGICAL NOTES ON THE ISLE OF PORTLAND. 



examination of the several localities of which his paper is the 

 subject. 



The Beach is described by our fellow member, Mr. Damon, 

 in his handbook of geology of Weymouth and the Island of 

 Portland (1884), as "a consolidated beach or breccia con- 

 sisting of pebbles, broken stones, gravel, comminuted shells 

 and sand, united into one common mass by a strong calcareous 

 cement." In 1869 Mr. Whittaker read a paper before the 

 Geological Society on the occurence of a deposit of shingle upon 

 the cliffs of the south-east part of the Isle of Portland. The 

 late Sir Charles Lyall took a part in the discussion on the paper 

 and with intuitive perception recognised the relationship of the 

 raised beach with the Bank, and insisted that the existence 

 of the Bank, proving an elevation of the land must be taken into 

 consideration in any theory as to the origin of the Bank. In 

 1871 Mr. Pengelly read a paper before the Devonshire Associa- 

 tion for the Advancement of Science upon the modern and 

 ancient beaches of Portland, in which he considered that the 

 direction of transportation of the " raised-beach," was from 

 west to east. Professor Prestwich's paper was read 

 before the Geological Society in 1874. He describes the beach 

 as resting upon a cliff of Portland rock waterworn on the 

 surface three and a half feet high and surmounted by a layer 

 of sand, one and a half feet thick; of the 28 species of shells it 

 contains, all, with one exception are of species now living in the 

 British Channel and are of a northern type, there being a marked 

 absence of more southern forms. At that period the coastline 

 was in all probability more direct from Torbay to the south 

 end of Portland, the sea having since made great encroachments, 

 removing the land, and with it the beaches. The old cliff 

 and raised beach are partially covered by a land-wash 

 consisting of loam and an angular debris, owing to a temporary 

 submergence of land to a depth exceeding the height of Port- 

 land, and on reemergence the broken-up beds, with remains of 

 land animals, and land and freshwater shells, protected by the 



