BRITISH ASSOCIATION MEETING. 



299 



region. It appears that the position of the rude flint-implements, which are 

 unequivocally of human workmanship, is such, at Abbeville and Amiens, as to 

 show that they are as ancient as a great mass of gravel which fills the lower 

 parts of the valley between those two cities, extending above and below them. 

 This gravel is an ancient fluviatile alluvium by no means confined to the lowest 

 depressions (where extensive and deep peat-mosses now exist), but is some- 

 times also seen covering the slopes of the boundary hills of chalk at elevations 

 of eighty or one hundred feet above the level of the Somme. Changes, there- 

 fore, in the physical boundary of the country, comprising both the filling up 

 with sedimeiit and drift, and the partial re-excavation of the valley, have hap- 

 pened since old river-beds were, at some former period, the receptacles of the 

 worked flints. The number of these last, already computed at above fourteen 

 thousand in an area of fourteen miles in length, and half a-mile in breadth, has 

 afforded to a succession of visitors abundant opportunities of verifying the true 

 geological position of the implements, 



"The old alluvium, whether at higher or lower levels, consists not only of the 

 coarse gravel with worked flints above mentioned, but also of super-imposed 

 beds of sand and loam, in which are many fresh-water and landshells, for the 

 most part entire, and of species now living in the same part of Prance, With 

 the shells are found bones of the Mammoth and an extinct Ehinoceros, R. ticho- 

 rhimis, an extinct species of deer, and fossil remains of the horse, ox, and 

 other animals. These are met with in the overlying beds, and sometimes also 

 in the gravel where the implements occur. At Menchecourt, in the suburbs 

 of Abbeville, a nearly entire skeleton of the Siberian Rhinoceros is said to have 

 benn taken out about forty years ago, a fact affording an answer to the question 

 often raised, as to whether the bones of the extinct mammalia could have been 

 washed out of an older alluvium into a newer one, and so redeposited and 

 mingled with the relics of human workmanship. Par-fetched as was this 

 hypothesis, I am informed that it would not, if granted, have seriously shaken 

 the proof of the high antiquity of the human productions, for that proof is in- 

 dependent of organic evidence or fossil remains, and is based on physical data. 

 As was stated to us last year by Sir Charles Lyell, we should still have to allow 

 time for great denudation of the chalk, and the removal from place to place, 

 and the spreading out over the length and breadth of a large valley of heaps of 

 chalk flints in beds from ten to fifteen feet in thickness, covered by loams and 

 sands of equal thickness, these last often tranquilly deposited, all of which 

 operations would require the supposition of a great lapse of time. 



That the mammalia fauna, preserved under such circumstances, should be 

 found to diverge from the type now established in the same region, is consistent 

 with experience ; but the fact of a foreign and extinct fauna was not needed to 

 indicate the great age of the gravel containing the worked flints. 



Another independent proof of the age of the same gravel and its associated 

 fossiliferous loam is derived from the large deposits of peat above alluded to, 

 in the Yalley of the Somme, which contain not only monuments of the Roman, 

 but also those of an older stone period, usually called Celtic. Bones, also, of 

 the bear, of the species still inhabiting the Pyrenees, and of the beaver, and 

 many large stumps of trees, not yet wtII examined by botanists, are found in 

 the same peat, the oldest portion of which belongs to times far beyong those 

 of tradition ; yet distinguished geologists are of opinion that the growth of all 

 the vegetation, and even the original scooping out of the hollows containing it, 

 are events long posterior in date to the gravel with flint implements — nay, pos- 

 terior even to the formation of the uppermost of the layers of loam with fresh 

 water shells overlying the gravel. 



The exploration of caverns, both in the British isles and other parts of 

 Europe, has in the last few years been prosecuted with renewed ardour and 



