TOPOGRAPHY OF BLAKENEY POINT. 9 



evidence as to the cause. Prior to the winter of 1910-11 the Long 

 Hills bank (No. 20, Fig. 2) was still straight, or at any rate only 

 slightly curved. In the early part of 1911 a series of gales 

 from the South-West broke off its exposed apex cutting it off 

 square and transporting the eroded materials so as to make a 

 new bank inserted at right angles to the stump of the old one 

 (Fig. 8). This observation gives the probable solution of how 

 the L-shaped terminals on the Marams banks and elsewhere 

 came into existence of course at a very remote period. 



RELATION OF MARSHES TO MAIN BEACH AND LATERALS. 



From the preceding general account of the main shingle 

 beach and the relation to it of the lateral banks, it follows that 

 the state of the materials in these two classes of structure must 

 be markedly dissimilar. In the one the pebbles ranged parallel 

 to the shore will remain mobile, so that the beach must slowly 

 encroach on the marshes behind ; whilst the laterals, on the 

 other hand, being set at right angles to the shore and in large 

 measure sheltered from wave impact, will enter on a state of 

 dormancy. 



One consequence of this will be the fundamentally different 

 relations obtaining along the lines of contact of the salt marshes 

 with the main bank and laterals, respectively. The marshes, as 

 their level rises, will gradually overlay the flanks of the laterals 

 with mud ; we get here mud resting on shingle. At the junction 

 of the marshes and main bank, however, the relations are precisely 

 reversed, for here it is the shingle (being mobile) that is being 

 drifted over the mud. It is needless to point out that these 

 physical peculiarities are reflected in the character of the 

 vegetation along these different types of junction. 



STABILISING EFFECT OF VEGETATION. 



Whilst the main bank tends to overwhelm the marshes 

 behind it, its travel will be liable to retardation by a variety 

 of circumstances. Thus the presence of bushes of Suteda 

 fruticosa, very general on parts of the Blakeney Bank, tends 

 to arrest the marshward flow of the shingle. The pebbles 

 become piled up on the weather face of the bushes, whilst on 



