554 J. Reid Moir — Sub-crag Flints. 



have naturally had a lot of rough usage while being transported 

 from one site to the other and have also suffered considerable 

 disintegration, as is clear from the cracked condition of the lumps. 

 Prolonged examination of the East Anglian flints from the three 

 horizons mentioned has shown that those below the Red Crag are 

 hard and sound, while those from the Middle Glacial Gravel and 

 Chalky Boulder-clay are much more easily cracked and broken up. 



It is therefore very interesting to find that the same rule holds 

 good at Selsey, where specimens, apparently of the same age as the 

 Sub-crag samples of East Anglia, are not so much broken as those 

 which appear to have come from Middle Glacial and Chalky Boulder- 

 clay deposits. 



The 'Sub-crag' specimens from Selsey are in some cases humanly 

 flaked, and the flaking is in every way the same as that seen upon the 

 East Anglian flints. The flakes are large and have been removed 

 by blows of considerable force delivered in a vertical direction and 

 resulting in smooth, clean surfaces, generally free from conchoidal 

 rippling. Fissures or small ' splits ', radiating from the point of 

 impact, are very often developed upon the surface of the flakes, 

 which frequently required repeated blows to detach them from the 

 block. The flints also exhibit a dark rich brown colour, and in many 

 cases well-marked ' weathered-out ' scratches. These peculiarities 

 are to be seeu upon the East Anglian Sub-crag specimens, and 

 moreover the forms of worked flints from the two sites are almost 

 exactly similar. 



(Mr. Heron Allen tells me that the smaller Sub-crag types such as 

 borers, scrapers, etc., have not been found at Selsey.) 



Out of the large series of Selsey flints about twelve have been 

 definitely worked by man, and only four of these were undamaged 

 and in a good state of preservation. These were all of a Sub-crag 

 type ; some of the others may at one time have exhibited human work, 

 but if so, subsequent natural fracturing has effectually disguised it. 



In order to demonstrate that the flints with cracks running through 

 their mass could easily be disintegrated, I dropped one upon 

 a tougher specimen, and, as I expected, the impact was sufficient to 

 shatter it in pieces. Some of these fragments, which of course bore 

 no real resemblance to man's work, were of a somewhat suggestive 

 shape, and if subjected to some amount of rolling by the sea might 

 very well deceive an unpractised eye. 



A visit to the exposure of these flints on the foreshore confirmed 

 the belief that the sea is at the present day breaking up the blocks, 

 and a single tap of the hammer is often enough to reduce them to 

 fragments. It is clear that the large majority of the Selsey specimens 

 have been fractured in the manner I describe, and a comparison of the 

 fractured surfaces with those produced by ray experiment shows an 

 exact agreement. There is the same dull, lustreless appearance, the 

 same uneven ' hackly ' fracture, and the same indisputable evidence 

 that the flint has broken along the lines of least resistance. There 

 is also no sort of resemblance in these fractures to those on the 

 other specimens which have been produced by heavy well-directed 

 human blows. 



