By the Rev. John Adams. 275 



Overlying the tertiary strata, there are in the Kennet valley east 

 of Hungerford, and on the hills on either side, beds of gravel 

 varying from a foot to twenty feet in depth. Many puzzling 

 questions cannot fail to suggest themselves to any one who inves- 

 tigates this deposit ; and many conflicting theories may be found 

 in geological authorities concerning it. A comparison was made 

 just now between the various formations of the neighbourhood, 

 and the various styles of architecture which may sometimes be 

 traced in the masonry of some old ruin ; but here in those gravel 

 beds we have fragments of every formation, specimens so to speak 

 of every style which the Great Master Builder has employed, all 

 mingled confusedly together, just as when a modern wall is con- 

 structed with the shattered materials of some grand old castle. 

 The greater portions of the mass may at once be pronounced 

 cretaceous ; we see at a glance that they are the ordinary chalk 

 flints of the country, broken up and slightly worn ; but along with 

 them we find occasionally pebbles of quartz, blocks of sandstone, 

 and now and then waterworn fragments of granitic rocks ; none of 

 which could possibly have been derived from the chalk. Here and 

 there, too, amongst rough brown flints very little worn by the 

 action of the water, and much discoloured by exposure to the 

 atmosphere, we encounter a stray flint which evidently belongs to 

 another family. It is quite different in appearance from its bed- 

 fellows, being perfectly round, smooth and black. We can only 

 account for its colour by saying that, unlike other flints, it must 

 have been buried in its early days beyond the reach of aerial 

 agencies, and so have preserved its natural blackness ; and for its 



beds, Journ. Geol. Soc. vol. 10, p. 123. But Mr. "Whitaker, while agreeing 

 generally with this theory, argues that at the western end of the London basin, 

 where they exist in greatest numbers, their origin may be traced to the Basshot 

 Bands. In adopting this latter hypothesis, I woiild remark, that they are found 

 everywhere in this district on the various strata overlying the Woolwich and 

 Beading series, and that they rarely bear traces of attrition, which would be 

 the case if they had been drifted hither from places where the Reading beds 

 have been denuded. As a rule, " it would seem," as Mr. "VVTiitaker remarks, 

 " that they have been quietly let down during the slow denudation and removal 

 of the softer materials of the beds of which they once formed part." Memoirs 

 of Geol. Survey, No. 7, p. 72. 



