A HISTORY OF KENT 



In discussing this branch of our subject it is important to remember 

 that there are no deposits in Kent that can be directly assigned to the 

 glacial agencies which produced such widespread effects in the country 

 north of the Thames. The great ice-sheet that gradually crept over all 

 the northern lands of Europe after the close of Pliocene times seems to 

 have attained its southerly bounds at the estuary of the Thames, so that 

 Kent lay just beyond its margin. But during this Glacial Period the 

 conditions must have been even more favourable to unequal or valley 

 erosion in the bare country, exposed to alternate freezing and thawing and 

 to heavy floods derived from the melting of the winter snows, than in the 

 county farther north, which was to some extent protected by its mantle 

 of permanent ice. Hence, while boulder-clays and glacial gravels were 

 being outspread upon the land to the northward, torrential denudation 

 was rapidly cutting into the Kentish hills and sending turbid floods, 

 active in erosion, along its main valleys. There has been much dis- 

 cussion as to the exact relationship between the Glacial drifts of the 

 north of England and the fossiliferous gravels and brickearths of the 

 Thames valley,* the circumstances being of course unfavourable for 

 direct correlation. Some part of the older ' superficial ' deposits of 

 Kent are likely to be at least of Glacial age, but as subaerial conditions 

 were persistent throughout the period and have continued to prevail 

 up to the present time, the fragmentary evidence which remains is 

 scarcely sufficient to enable us to recognize the limits of the period in 

 Kent. 



Recent Deposits. — Between the deposition of the old river-drift 

 with remains of extinct mammals and present-day conditions there 

 have been many intermediate stages, of which some record is pre- 

 served in the lower terraces and recent alluvium of the valleys. 

 These newer deposits all indicate a shrinkage in volume of the rivers, 

 and they also show that within comparatively recent times the land 

 has stood somewhat higher than at present. Excavations for docks 

 and other works below the level of high tide in the Thames valley 

 below London, especially between Woolwich and Erith, have revealed 

 layers of peat with trunks of trees, including the oak and yew, 

 indicating forest growth in situ, this peat being interstratified with beds 

 of marsh clay, the whole resting on river-gravel and sand. Where 

 fossils occur in these deposits they are all of species still living ; and 

 traces of human work of Neolithic and later date are also occasionally 

 found. The marshes of the lower Thames and of the mouths of the 

 Medway and the Stour are further examples of these recent alluvia, and 

 less extensive deposits of the same kind fringe the streams in the 

 interior. 



are West Wickham, Swanscombe, Milton Street, Ash, Darent, Rainham, etc. G. Clinch, ' On Drift 

 Gravels at West Wickham,' Quart. Jouitt. Geo!. Soc. (1900), Ivi. 8 ; J. M. Mello, 'On some Palaeolithic 

 Implements of North Kent,' Re/i. British Assoc, for 1899 (Dover), p. 753, etc. See also article 

 on ' Early Man ' in present volume. 



1 For summary, see Mem. Geol. Survey, 'Geology of London,' pp. 353-87. 

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