178 



Froceedincjs of the Roijal Iris/i Academ tj. 



of sharp and little patinated flakes. This was a portion of the surface- 

 gravels that had not been disturbed, or possibly the site of comparatively- 

 recent flaking. 



The patination of a flint is of doubtful value as an indication of 

 antiquity. It depends chiefly on the circumstances of exposure, the 

 nature of the bed, and quality of the flint. The conditions of exposure 

 on a beach ajipear to be specially favourable to rapid patination. 

 Where flints have remained unexposed in a non-porous deposit, they 

 are often found to be quite fresh ; and we have taken naturally broken 

 flints from the Boulder-clay which were translucent, and retained the 

 freshness of fracture and edges, as if only broken yesterday. 



It may be mentioned that flints when first taken from a deposit 

 are often dark, and partly translucent, but when they dry out become 

 grey and opaque. Several flakes taken from the aluminium works 

 section have turned grey and opaque in the Museum ; in fact, an 

 incipient patination maybe said to have begun. The evidence of the 

 unrolled flakes in the lower beds points to the working of the flints 

 having been contemporary with the laying down of the gravels. 



The series of flakes from the section in the aluminium works 

 (see Plate YI.), which we will now describe in detail, is perhaps the 

 most instructive on this point. 



The disturbed surface layer (1 foot 3 inches) yielded weathered and 

 abraded flakes in the usual abundance, such as fig. 5, JN'os. 1 to 5. At 

 the bottom this layer passed into finer gravel (7 inclies), in which a 

 considerable number of unweathered and sharp flakes were found, 

 representing a comparatively undisturbed deposit or pocket (fig. 6, 

 Nos. 1, 2). Eelow this was a layer of coarse stratified gravel 

 (6 inches). In this layer a few coarse weathered flakes occurred, 

 similar to the surface flakes. ]N"ext in order came a band of sand 

 (10 inches) ; in it a few broken flints were found, and, at the bottom 

 of the sand, resting on the next bed, some well-struck flakes and a 

 rude flint " celt" (fig. 6, Nos. 3, 4). The flakes and celt from this 

 sand-baud were patinated, but not deeply, and sand-stained a brown 

 colour, which easily distinguished them from the flints from tlie other 

 beds ; the edges were sharp. 



At the bottom of the sand-band was a thin layer of rolled pebbles, 

 about 4 inches thick, at the base of which was a thin ochreous deposit 

 from decomposing basalt pebbles. In this ochreous deposit numerous 

 flakes were found quite unweathered and sharp, marked in places with 

 ochre stains (fig. 6, iN'os. 5, 6). lielow this stony layer came a bed of 

 gravelly clay (1 foot 3 inches), resting directly on the Uoulder-clay. 



