548 *S^. H. Warren — The Eolithic Controversy. 



not been my argument, as anyone who will read my published papers 

 may find. 



In my opinion, the object of the investigation of flint is to ascertain 

 hy experiments its chipping properties. 



This investigation has shown, as I have indicated in an earlier part 

 of this article, that when suitable raw material is subjected to a force 

 of crushing or of diflerential movement under pressure eolithic 

 chipping inevitably takes place. 



Now one of the most notable features which is associated with the 

 eoliths in the field is the striation of the surfaces of the flints. 

 Whether this striation be due exclusively to ice-action, as some have 

 claimed, or whether it be more commonly due to the active process of 

 solifluction or soil-abrasion.^ (as I have previously suggested thiit it 

 mi^ht be named), does not affect the immediate question of the 

 eoliths. In either case, striation of the flint surfaces indicates move- 

 ment under pressure. 



I venture to ask that if experimental movement under pressure 

 inevitably produces eolithic edge-chipping, is it so unreasonable to 

 suppose that natural movement under pressure will also have the 

 same chipping effect when operating upon similar material? 



I hope to describe before long the experiments which I have been 

 conducting for the purpose of discovering the amount of chipping 

 produced by difl'erential movement under various pressures.'^ And 

 also the comparison of this with the amount of the subsoil pressure 

 which falls upon stones in difl'erent soils according to their superficial 

 area and their depth beneath the surface. This is a somewhat 

 complicated subject and one which cannot be dealt with adequately 

 within the compass of a short article. I will only say here that there 

 is no inherent difficulty, so far as the necessary pressure is concerned, 

 in the chipping of the Kentish type of eoliths by the action of soil- 

 abrasion during the sliding or solifluction of drift deposits.^ 



With regard to the larger chipping upon the sub-Crag flints, it is 

 perfectly true that this has not been reproduced experimentally by 

 mechanical force. But I am unable to follow Mr. Moir in viewing 

 this as a matter of such great moment, for the simple reason that no 

 experiment of differential movement under the pressure which exists 

 beneath 20 or 30 feet of drift, to say nothing of the weight of an ice- 

 sheet, has yet been made upon flint. In making such experiments it 

 would be necessary to take into account the structure, size, shape, 

 and flaking qualities of the raw material used ; for a result which is 

 inevitable upon one piece of flint is unattainable upon another. 



For the present one can only judge of the sub-Crag flints upon 

 general lines, and by inference from the known lesser to the unknown 

 greater. In my judgment the sub-Crag chipping is only what one 

 might expect to take place where forces of greater magnitude are 

 operating upon larger material. 



^ S. H. Warren, Journ. Anthrop. Inst., vol. xxxv, p. 349, 1905. 



^ Since this was written the paper has been read at a joint meeting of the 

 Koyal Anthropological Institute and the Prehistoric Society of East Anglia on 

 February 17, 1914, but it is not yet published. 



^ See also Abstracts Proc. Geol. Soc, November 28, 1913. 



