400 Sir R. H. Hoirorth—The Mammoth and the Glacial Drift. 



see any evidence in this. The sections clearly show that the bone 

 beds are overlain by trail as Mr. Irving himself admits (Q.J.G.S. 

 vol. XXXV. p. 670), and they rest on the Greensand and Chalk-marl. 



In the adjoining County of Bedford I know of no direct evidence 

 of super-position, but inasmuch as a great deal has been made of 

 such evidence as is there forthcoming by the advocates of the so- 

 called post-Glacial date of the Mammoth and Palaeolithic Man, it 

 may be well to devote a few words to them and especially to the 

 section at Biddenham. 



Mr. Prestwich has given an admirable section of the deposits in 

 the valley of the Ouse at this point (Q.J.G.S. vol, xvii. p. 364). 

 From this section it seems that the valley of the Ouse has been scooped 

 out of the Oolitic rocks known as Cornbrash. In the lowest portion 

 of the trough so created runs the river Ouse, which has deposited a 

 certain amount of alluvium along its course. On a higher level in 

 the valley is the bed of gravel in which the flint implements were 

 found. Lastly, the bounding heights of the valley on each side are 

 capped with Boulder-clay, which stretches for miles in all directions 

 (Lyell, op. cit.). The theory generally adopted is that the Boulder- 

 clay was once continuous across the valley, and that the valley has 

 been scooped out of it. This is the view of Mr. Prestwich, 

 Sir J. Evans, Sir Charles Lyell, etc., etc. 



One thing is clear, if the Boulder-clay once occupied the valley in 

 this way the scooping out must have been most complete, and the 

 floor of the valley laid bare ; for as Sir Charles Lyell expressly tells 

 us the two implements first found in the gravel were found " at the 

 depth of 13 feet from the surface and rested immediately on solid 

 beds of Oolitic limestone," and so he reprints it in his section. At 

 this point, then, the evidence is plain that there is no superposition 

 of the flint-bearing beds on the Glacial clay. The former lie directly 

 on the floor of the vallej^ and such evidence as is forthcoming at 

 this point is of an essentially secondary and deductive character 

 and certainly does not warrant the assertion of Sir Charles Lj^ell, 

 that the Bedford sections teach us that the fabincators of the antique 

 tools and the extinct Mammalia coeval with them were post-Glacial 

 (id. p. 217). But let us proceed somewhat further. In 1866 Mr. 

 Flower described the discovery of flint implements, at Thetford, on 

 the Ouse. These he tells us were obtained from 12 to 15 feet below 

 the surface and within a foot or less of the ChaJh on ichich the gravel 

 rests ; and some were found in some gravel filling potholes in the Chalk 

 (Quart. Journ. Geol. Soc. vol. xxii. p. 567). Here the evidence 

 carries our case still further, for not only does the gravel lie imme- 

 diately on the solid rock, but also in the potholes ; so that the 

 sweeping out of the Boulder-clay must have indeed been complete 

 and profound. Let us turn to another site in the same valley, 

 namely, at Summei-house Hill, where Mr. Wyatt found flint imple- 

 ments which had come from beds containing a similar assortment of 

 Mammalian bones and land and freshwater shells to those found 

 nearer Bedford. He gives an admirable section across the valley at 

 this point showing a state of things precisely the same as in the 

 sites already referred to (Quart. Journ. Geol. Soc. vol. xx. p. 185). 



