part 3] A NATURAL 'EOLITH ' FACTORY. 247 



by their mineral condition. But this need not occasion undue 

 misgiving in the separation of the work of Nature from the work 

 of Man : such exceptional specimens are condemned by their 

 associates. 



We must distinguish a geological deposit of chipped flints from 

 the debris of a prehistoric chipping-floor, by taking fairly repre- 

 sentative groups. One can easily become unconsciously deceived 

 by over-selection. 



The characters of human and non-human flaking can only be 

 properly appreciated by first-hand experiment ; but it is hoped that 

 a comparison of 10 c (p. 240), and 22, 23, & 24 (PL XV) will be 

 of material assistance. 



(22) PL XV. — Photograph of two conjoined flakes showing 

 normal pressure-characters ; that is to say, the bulb consists of a 

 broad, but ill-defined and only slightly-elevated, swelling. Dimen- 

 sions of the two together =80 x 93 x 22 mm. 



(23) PL XV. — Photograph of four conjoined flakes, also 

 showing normal pressure-characters, but ' struck ' from an appa- 

 rently well-prepared platform. 53 x 50 x 12 mm., 88°. 



(24) PL XV. — Photograph of a large flake with conical bulb 

 which is practically indistinguishable from a normal ' human ' 

 example : that is to say, the bulb has more the form of a sharply- 

 defined cone, 1 it is more elevated, and also cross-cut by the eraillure 

 which was formerly supposed to be the exclusive character of the 

 human blow. This specimen is of non-pressure character, and 

 must represent some sudden jolt or jerk in the soil-movements. 

 118 x 136 x 23 mm., 80°. 



(E) Exceptional Forms. 



(25) PL XV. — Adze-like form, with good flaking at the end. 

 This specimen had been pressed into the Chalk, and the photo- 

 graph shows the slickensiding on the Chalk which still firmLy 

 adheres to the flint in the hollow to the left of where the numeral 25 

 is placed. All the flakes were recovered. 97 x 60 x 38 mm., 70°. 



(26) P. 246. — Small pseudo-racloir, made from a good flake with 

 bulb and eraillure. As in other instances in the Bullhead series, 

 there are numerous further secondary flakes in process of being 

 removed from the trimmed edge, but the fractures are not yet suffi- 

 ciently completed to cause their separation. The second drawing,. 

 26 x, shows the approximate appearance which the specimen would 

 assume were the present incipient flakings completed. 56 x 45 



x 29 mm., 80°. 



(27) This is a very fine ' side-scraper.' One has to search far 

 in order to find an Eolith that is its ecpial. 83 X 98 X 31 mm., 85°. 



1 These characters refer to the effects of a simple, direct, human blow- 

 There are more advanced techniques of human flaking- which produce entirely 

 different results. 



