290 



THE GEOLOaiST. 



over any downs, across any cbalk country, and not pick up, if you 

 please, tons upon tons or cart-load upon cart-load ? If one sort, why 

 not the other ? Is the proportion of flint-implements to unworked 

 stones likely to be less in the disintegrated gravel-bed strewn over 

 the soil than in the solid untouched stratum lying intact in the 

 earth ? And if not, are we less likely to find flint-implements 

 on the surface of the soil than in the gravel-beds beneath it ? We 

 are sure we need not reply to these questions — our readers will have 

 answered for themselves. 



7. Is it admissible to suppose tliat products so similar ivere manu- 

 factured^ the one set at tJie commencement of the quaternary period, 

 the other during the notu existing period, seeing that an, immense inter- 

 val of time separates the two epochs /-—Supposing the facts to be true, 

 — but the facts are not stated by M. Grras, as already observed, — it 

 might be so, if it be admissible to believe that small tribes or scat- 

 tered individuals of a nation or race of mankind could live on after 

 the destruction or distribution of the great bulk or mass of the nation 

 or race. Just as some modern uncivilized tribes are presumed to be 

 the descendants of once numerous and powerful peoples. Just as 

 British and Celtic articles may be met with in Saxon and Eoman 

 graves; just as medieval relics are still treasured in our houses, so 

 may we always expect to find some relics of more ancient races 

 amongst the relics of the more modern ones. The case put however 

 by M. Gras is a presumption, and it is futile to fill our pages with 

 suppositions in reply to suppositions. We go on therefore to M. 

 Gras' final summary : — 



" To all these diificulties one single fact only can be opposed, that, 

 namely, of the absence of all apparent disturbance in the diluvium ; but 

 this fact is not a peremptory reason, for it may be explained in a plausible 

 manner. 



" Let us refer the manufacture of axes, which everything proves to have 

 formerly been carried on in the valley of the Somme, to the origin of his- 

 toric times. It is certain that the nien occupied in this employment were 

 not obliged to go very far to procure the first material that Avas necessary 

 for them. By digging in the soil to a moderate depth, they found a great 

 choice of flints ready to be cut. This was probably even the reason why 

 this kind of industry sprang up in the country. The digging of flints might 

 take place in two ways, by pits or by galleries. The first means was the 

 most costly, since it was necessary to pass through the brown argillaceous- 

 sandy dihivium before arriving at the flints, and because the removal of 

 the rubbish nuist take place vertically. The digging by horizontal 

 gallcric\^ opiMiod on the side of the valley, taking advantage of the steep 

 banks, a\ as evidently preferable. The excavation of these a'ncient galleries 

 is so lar from being unlikely, that even at the present day such are still 

 made for the extraction of gravel. I have seen one at St. Acbeul, and I 



