The Wash.

We have now carried our examination of the Fen Beds up to the sea, but to understand this interesting area we must cross the sea bank and see what is happening in the Wash. There is no peat being formed there, nor is there any quantity of drifted vegetable matter such as might form peat. There are marginal forest beds near Hunstanton and Holme, for instance, and it is not clear whether they point to submergence or to the former existence of sand dunes or shingle beaches sufficient to keep out the sea and allow the growth of trees below high water level behind the barrier, such as may be seen at Braunton Burrows, near Westward Ho, or at the mouth of the Somme. What is the most conspicuous character of the Wash is that the upland waters, now controlled as to their outlet, keep open the troughs and deeps while tidal action throws up a number of shifting banks of mud, sand and gravel, many of which are left dry at low water. Along the quieter marginal portions fine sediment is laid down, and relaid when storms have disturbed the surface. On these cockles and other estuarine molluscs thrive. Before the sea banks were constructed these tidal flats extended much further inland.