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BLAKENEY POINT, NORFOLK
   Continuing along the road, past the “ Dun Cow”, the windmill and village of Salthouse, a causeway leads across the marshes to the conspicuous Rocket House. All along this front to the corner of the Cley Marshes are the remains of the sea-wall of 1851. This wall, 2 miles in length, has been overtaken by the beach, which now lies piled up against it for a large part of the distance, and at many points is level with the top of what remains, and running over.
   The sea-wall is breached at numerous points, and no section over 100 yards in length remains intact. The gaps in the wall have been produced by the sea washing over the crest and eroding the mud, whilst at some spots when the marshes were in flood the wall has been undercut by scour from the south side.
   With the deepening of the gaps the sea began to wash the shingle through, spreading it out in the form of circular detrital fans standing about 2 feet above the marsh level.
   Thus, 100 yards east of the Rocket House, a 20-foot gap has admitted a level detrital fan 100 feet across (north to south) and 100 feet wide (east to west). The height is approximately 2 feet.1
   Opposite the “ Dun Cow” at Salthouse there is a very broad breach with fan to correspond. In 1913 the surface of the latter was beginning to be colonized by Horned Poppy and Dock. About 400 yards farther west, opposite a pair of drains crossing the marsh, a breach was just beginning, and pebbles were already drifting over the gap. At one place a number of breaches occui close together, and much shingle has drifted through them. The lines of flow are marked by gullies like those in percolation ravines, whilst shingle is deflected and accumulates under the lee of the surviving wall fragments, reaching a height of perhaps 4 feet, and recalling the relation that obtains between a Psamma tuft and the “ tail” of sand that accumulates under its protection. In the case of the Psamma the agent of transport is wind, whilst the shingle, of course, is carried along by water.
   The areas of marsh covered by these detrital fans are lost for grazing, whilst the gaps have to be fenced to prevent cattle straying on to the beach.
    1 These dimensions were noted in March, 1913. The damage may have increased since that date.