By S. B. Dixon. 



143 



domestic or warlike article nor of any bones. From the appearance 

 of the gravel beds, and the irregular distribution of the material, 

 and the river silt mixed in one part with the flints, it is very 

 probable that much that was originally deposited was afterwards 

 washed up and re-deposited and re-arranged, especially that at the 

 base of the slope. Here the flints are mixed with river silt instead 

 of clay, and the implements were far more numerous and showed 

 signs of superior workmanship. In these beds were found the 

 polished implements previously referred to, and two or three 

 suggestions have been made to account for this polish. It is found 

 on both worked and un worked flints, and those affected by it 

 occupied quite a limited area. Polished flints, similar to those 

 found at Knowle, have been found in a few other localities 1 and 

 two or three explanations have been given to account for this 

 unusual appearance. Some consider that it arises from the con- 

 stant passage over the surface of the flint, when lying on the 

 ground, of very fine blown sand, at a period of drought when the 

 river sand was dry and loose — a similar appearance being often 

 found in pebbles in the desert, the polish being spoken of as "the 

 desert polish." With some the whole of one side has been affected, 

 and with others a part only, the extent depending on the portion 

 exposed. Another suggestion is that the constant flow of water, 

 mixed with the finest sediment (or even without a sediment) 

 would after a long period produce the appearance ; but as both 

 of these suggestions indicate a long continuous friction, there is 

 the grave objection that the inequalities of the surface have not 

 been worn away, but stand out on the polished surface as if no 

 friction had ever taken place. The fractured surfaces of most of 

 the flinty substances (flint, agate, chalcedony, opal, &c.) show a 

 number of concentric circles, which are slightly elevated and which 

 would be first affected by friction. In the polished flints from 

 Knowle these concentric circles have not been affected but stand 

 out plainly from the surface, showing no sign of rubbing. In one 



1 I mention this on the authority of Mr. Story Maskelyne who has also 

 given me the suggestions as to the origin of the polish. 



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