Geological Society. 117 



broke up many of the secondary strata, from the chalk to the lias in- 

 clusive, and the debris thus produced, together with numerous masse* 

 of ancient rocks, was spread by a rush of water over the surface of the 

 tertiary formations and the chalk, in some places to a depth of 400 

 feet, constituting the beds of drift clay,&c, which occupy so great an 

 area in Suffolk. 



6. Previously to this diluvial action, and after it, the rivers of the 

 then dry land bore to the sea, animal and vegetable remains, vestiges 

 of which occur on the Norfolk coast and elsewhere. 



7. The climate of this part of the globe was at that era different 

 from the present. 



8. After this period, and probably in prolongation of the first great 

 catastrophe, a series of shocks acting from below, shattered the surface 

 and gradually elevated the whole district, till the crag attained the 

 height of nearly 100 feet above the level of the sea; and by this 

 movement were produced the valleys or lines of fissure, through which 

 the drainage of the county is effected. 



9. No great convulsions have since taken place. 



10. By the action of springs, and the constant battering of the sea, 

 the superficial contents of the London clay and crag have been re- 

 duced several miles, vestiges of their former extent being traceable in 

 rocks and sandbanks nearly always submerged. 



1 1. By the set of the tides vast accumulations of shingle and sand 

 have been formed at projecting points, protecting in some places the 

 cliffs from further destruction ; but at Harwich harbour they have 

 blocked up the ancient estuary, and compelled the Stour and Orwell 

 to form a new outlet. 



1 2. The average amount of annual degradation of the coast is about 

 two yards in breadth ; and in consequence of the conformation of the 

 ridges of crag and London clay, the cliffs will gradually diminish into 

 a low sandy shore. The period estimated by Mr. Clarke for effecting 

 this destruction is another century. 



A paper "On the raised beaches of Saunton Downend and Baggy 

 Point," by the Rev. David Williams, F.G.S., was then read. 



The first of these breaches extends from B rami ton Burrows to Down- 

 end Point ; the other on the N. coast of Croyd Bay, from near the 

 limekilns to half way to Baggy Point. These beaches were described 

 in the paper read by Professor Sedgwick and Mr. Murchison on the 

 14th December, 1836*; and Mr. Williams in this paper fully agrees 

 with the conclusions drawn by those authors, relative to the beaches 

 having been raised. 



In addition, however, to the proofs afforded by the abundance of re- 

 mains of existing British marine shellsintheseaccumulations, cemented 

 together by calcareous infiltration into a tough sandstone, he stated 

 that he had discovered in many places, from 6 to 10 feet, above the tidal 

 level, and at the line of contact of the beaches with the old slate rocks 

 of the district, countless Balani attached to the surface of the latter, 

 but so firmly entangled in the substance of the former as to be sepa- 

 rated with its fragments. A large granite boulder also rests on the 

 * See our last volume, p. 477. 



