132 The Palaeolithic Implements and Gravels of Knowle, Wilts. 



them, and with the mineral condition of the gravels in which they 

 occur, that render a further investigation desirable. 



The pit is some 40 or 50 feet above the level of the turnpike 

 road from Marlborough to Hungerford, near the summit of a piece 

 of rising ground, 460 feet above the sea. It exists as a semicircular 

 cutting into the side of the hill, some 10 to 14 feet in depth, with 

 coarse flints above, and smaller stones embedded in a ferruginous 

 sand, below. It may be noted that extremely few pebbles occur 

 in the pit, and that the implements are principally found in the 

 lower and more sandy layers. In this district an abundant supply 

 of good workable flint must have been ready to hand, since denu- 

 dation has proceeded so far that little of the Upper Chalk (in 

 which alone flint occurs) is left. 



Another point of interest is afforded by the composition of the 

 gravel. It has been spoken of by a geologist of much experience 

 as the purest flint gravel he has ever seen. As the result of five 

 days working in- the pit he found five quartz pebbles, one lump of 

 iron pyrites, four of ferruginous lower greensand, and six pieces 

 of quartzite and sarsen, but no other examples of foreign rock. 1 



The implements found at Knowle have chiefly been made of 

 flints derived apparently from gravels of still older date. Where 

 there are portions of the old chalk crust remaining, they have 

 generally been much worn down. 



All the flints from the Knowle pit are free from the dark brown 

 ferruginous stain which is so distinctive a feature of the Kentish 

 plateau gravels. This does not imply the entire absence of iron 

 oxide. A considerable amount is in fact present, particularly in 

 the sand, and many of the flints themselves show thin patches of 

 ferruginous deposit. It is, however, specially to be remarked that 

 the 'worked surfaces of the Knowle palseoliths are altogether free 

 from ferruginous deposit, or indeed from any stain. 



In the dark-coloured sand from the bottom of the pit, there is 

 also a noticeable proportion of manganese dioxide, and small patches 



1 We should here state on the authority of Prof. Boyd Dawkins, that there 

 are two or three chert implements, among those from Knowle, in the Brighton 

 Museum. 



