part 1] SANDS AND GKAVELS AT LITTLE HEATH. 37 



that the water depositing the sands had a gentle flow. Occasionally, 

 however, the formations merge one into the other, a thin deposit 

 of sand, or sandy loam, being followed by another thin deposit of 

 the gravel. This is probably due to locally-increased tidal action, 

 giving rise to stronger currents. 



The underlying gravels at the junction have often an undulating- 

 surface, even where the bedding of the sands is horizontal. These 

 undulations are sometimes so pronounced as to suggest the appear- 

 ance of tidal beaches. The term ' tidal beaches ' is used designedly, 

 in contradistinction to the 'storm-beaches' thrown up to such a 

 height as to be placed beyond the reach of further tidal deposits. 

 In the latter case, one would not look for the dense infilling of 

 sand and small pebbles, which is so prominent a feature in the 

 Little Heath deposits. As a case in point, almost the whole of the 

 Dungeness promontory, several square miles in extent, is made up 

 of a succession of huge storm-beaches : the sand-filling is almost 

 totally absent, and will remain so unless and until subsidence takes 

 place. The beaches at Little Heath were on a very much smaller 

 scale, and remained within reach of tidal action by which the 

 infilling was accomplished. No other exposure of the surface of the 

 gravels on any considerable scale is now available for examination ; 

 but the evidence of men who have worked in these beds for road- 

 metalling in the past, seems to point to the existence of similar 

 undulations on a larger scale in other parts of the Common. 



At the apex of one of the beaches, and at the junction with the 

 loamy sands, a very big pebble weighing several pounds was found 

 resting upon a bank composed, to a considerable depth, of uniformly 

 small pebbles. This occurrence seems suggestive of tidal force. 



It may here be stated that the laminae of the loamy sands in the 

 hollows of the beaches do not always follow the contour-line of 

 the beach, but are deposited more or less horizontally, occasionally 

 with a slight local unconformity. This seems to suggest that the 

 water gained sudden access through one of the beaches, depositing 

 first the heavier burden of sand, and then the lighter of clay in 

 suspension, this operation being repeated by successive storms or 

 high tides, leaving the sands high and dry during the intervals. 

 Hence the sun-cracks. Hence also the variation in thickness and 

 arrangement of the beds referred to by Mr. W. Humphrey, and 

 their entire absence in other places. 



The fact that the surface of the clay-partings never shows signs 

 of erosion, either from water or from subaerial agencies, seems to 

 show that the various layers of the sands were deposited at fairly 

 frequent intervals, and that the flow of water was hereabouts very 

 gentle in character. This is what might be expected, on the 

 supposition that the water was tidal, and flowed in from a 

 distance. 



No. 3. The stratified coarse gravel. — The coarse material 

 consists almost entirely of Reading pebbles and waterworn flints. 



