EARLY MAN 



implements from neighbouring gravels such as these. They prove beyond 

 any doubt that there were several — probably many — different periods of 

 human occupation in the ' drift ' age, separated from one another by periods 

 of vast diluvial action. The earth v^ras swept clean of its implements by 

 one great set of floods ; then man reappeared, and his implements in turn 

 were swept down into gravels, and so on. How many times this process 

 was repeated it is impossible to say ; but as it is difficult to believe that 

 each recurrence of habitable conditions with the alternating flood conditions 

 was other than of very long duration, the total length of time thus adumbrated 

 for the whole ' drift ' period must have been immense — far beyond anything 

 that has hitherto been tentatively assigned to it. 



We are now in a position to sum up the knowledge gained from this 

 discussion of the geological conditions of the ridge. 



1. The first and most important point is the evidence just brought 

 forward that the whole ' drift ' period was made up of sub-periods during 

 which the land was alternately habitable and under diluvial conditions. 



2. That the ' drift ' period must have been of sufficient length to include 

 not only the vast deposits of the Thames Valley, but also large and important 

 deposits in Suffolk which are not represented in the Thames Valley. 



3. That the patina of ' drift ' implements, certainly in Suffolk and 

 probably everywhere else, was formed before they got into their present positions 

 in the gravels. There is every reason to believe that this formation of patina 

 on flints of good quality is of very slow growth ; for no neolithic implement 

 has ever been found presenting anything like the ochreous patination so 

 distinctive of a large proportion of ' drift ' implements. Yet even at the most 

 moderate computation neolithic implements are several thousands of years old. 



4. This being so, the very varied and in many cases the very deep 

 patination of many of the Warren Hill ovates points to the period represented 

 by them as having been very long, probably greatly exceeding anything that 

 we can allow for the whole Neolithic Age, including the time that has elapsed 

 since it came to an end. Yet this Warren Hill period is merely one of many 

 sub-periods of the great ' drift ' age. We begin here to get a glimpse of the 

 vast extension of palaeolithic time. 



5. Passing on from the lessons taught as to the ' drift ' period we come to 

 the next great division of palaeolithic archaeology, the ' Mousterian.' After 

 the 'drift' age had passed away, and before the Mousterian was established, we 

 saw that a wholly new distribution of geological forces took place by which 

 the valley and the river in it were changed from their original character. The 

 river disappeared, and the land to the west of the valley was shaved down to 

 its present relative level ; the lowering process being carried right up to the 

 western side of our ridge, which then formed a bank sloping down from the 

 higher ground to the east to the newly excavated lower ground to the west. 

 And on this bank, the shore probably of some lagoon, lived ' Mousterian ' 

 man, whose implements are found buried in the brick-earth deposited by 

 the muddy waters of the gradually rising lagoon. This is probably the only 

 instance where we get a glimpse of the order of time that elapsed between the 

 ' drift ' epoch and that of ' Mousterian ' man. Here we have the sequence : 

 ovates of Warren Hill ; their patination ; their accidental chipping and its 

 patination; the flood conditions that washed them into the gravels; recurrence 



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