Vol.51-] OF EASTERN EAST ANGLIA. - 497 



is composed essentially of quartzose sands full of flint-pebbles, almost 

 as much worn and as numerous as in the Lower Tertiary sands of 

 Blackheath. With these are mixed a good many white and rose- 

 coloured quartz-pebbles, 2 pebbles of lydian-stone, 3 large flattened 

 pebbles of light-coloured quartzite, 4 rolled and worn fragments of 

 Lower Greensand chert.' Of these materials the first forms the 

 great bulk of the shingle, the rest of the contents being sporadic 

 and scattered. 



The first thing that will be obvious to any one who examines 

 this Southwold or Westleton shingle is the fact that it is not in 

 place, — that it is in every sense a true Drift. Its component parts 

 were not put together as we find them, nor were they ground and 

 polished on the spot. The larger part of the pebbles — namely, the 

 flints — are foreigners, and strangers to the locality where we meet 

 with them. The flints, no doubt, were derived from Chalk some- 

 where, but the Chalk in this part of England is buried deep down 

 under beds of Tertiary age, and its flints are absolutely protected 

 from any possible intrusion of a denuding force, whatever it may 

 have been. So with the chert. It is quite impossible to suppose 

 that these beds of shingle, lying as they do, sometimes on Crag- 

 beds, sometimes on London Clay, have derived their flints from 

 horizons in which these materials are conspicuously absent. 



The next question is, whence has this drift come ? If we are to 

 get a hint of the place whence the shingle has come we must first 

 examine its composition. If we do so examine its contents, we 

 shall find that we can separate them into two classes of materials. 

 In one class I would put the smoothed flints and some of the green 

 quartz-pebbles, and in another the rest of the ingredients. 



If we examine the flints and quartz-pebbles apart from the other 

 material, it is impossible to avoid the conclusion that they are 

 essentially the same in character with the pebbles in the beds of 

 Eocene-shingle age found elsewhere. This was long ago urged by 

 Prof. Prestwich and others, and it seems as plain as can be that this 

 so-called Westleton Shingle is essentially a disintegrated bed of 

 Eocene gravel dating either from the period of the Plastic Clay 

 series, of which typical beds are found in situ at Woolwich and 

 Reading, or from the same horizon as the Blackheath Beds. 



Turning from the flint-pebbles to the other ingredients in the 

 shingle, I cannot quite agree with Prof. Prestwich in his conclusion. 

 He connects certain light-coloured quartzite-pebbles in the shingle 

 with similar pebbles found in Belgium, while he brings the fragments 

 of ragstone directly from the Greensand series of Kent, and on the 

 strength of this brings the shingle itself from the south and east. 

 Now I believe myself that these other ingredients, whatever their 

 ultimate origin, were directly derived either from the Plastic Clay 

 or the Red Crag. Prestwich states that he has found the large 

 pebbles of white or light-coloured quartzite occasionally in the 

 shingle-beds of the Woolwich and Reading series. These, as well 

 as the other pebbles, may, however, have come from the Red Crag, 

 where they actually occur, as was long ago pointed out by Prestwich 



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