94 GOSSIP ON ANTIQUITY OF MAN. 



seen on the slopes of the hills, as at h and c. The general surface 

 of the upland region is covered continuously for miles in every 

 direction by loam or brick earth (3) about five feet thick, devoid of 

 fossils. To the wide extent of this loam the soil of Picardy chiefly 

 owes its great fertility. Here and there we also observe on the 

 chalk outlying patches of tertiary sand and clay, with eocene fos- 

 sils (2), the remnants of a formation once more extensive, and 

 which probably once spread in one continuous mass over the chalky 

 before the present system of valleys had begun to be shaped out. 

 It is necessary to allude to these relics of tertiary strata, of which 

 the larger part is missing, because their denudation has contributed 

 largely to furnish the materials of gravels in which the flint imple- 

 ments and bones of extinct mammalia are entombed. From this 

 source have been derived not only regular fonned egg shaped peb- 

 bles, so common in the old fluviatile alluvium at all levels, hut 

 huge masses of '^sandstone several feet in diameter. The upland 

 loam also (3) has often, in ho slight degree, been formed at the 

 expense of the same tertiary sands and clays, as is attested by its 

 becoming more or less sandy or argillaceous, according to the nature 

 of the nearest eocene outlier in the neighbourhood. The average 

 width of the valley of the Somme between Amiens and Abbeville 

 is one mile. 



" It will be seen by the description given of the section, that 

 (3 a) indicates the lower level gravels, and (2 a) the higher ones, 

 or those rising to elevations of eighty or a hundred feet above the 

 river. Newer than these is the peat (5), which is from ten to 

 thirty feet in thickness, and which is not only of later date than 

 the alluvium (3 a) and (2 a), but is also posterior to the denudation 

 of those gravels, or to the time when the valley was excavated 

 tln-ough them. Underneath the peat is a bed of gravel (4), from 

 three to fourteen feet thick, which rests on undisturbed chalk. 

 This gravel was probably formed, in part at least, when the valley 

 was scooped out to its present depth, since which time no geological 

 change has taken place except the growth of the peat, and certain 

 oscillations in the general level of the country. A thin layer of im- 

 pervious clay separates the gravel (4) from the peat (5), and seems 

 to have been a necessary preliminary to the growth of the peat." 



I may sum up the substance of this description in a few words. 

 If my theory of inversion be sufficient to account for the finding of 

 the remains of man in mixed strata — no violence will be done 

 either to the scriptural or geological record. They will fall into 

 their proper place in the order of creation. So also will those of 

 the recent animals cotemporary with man: and so also will those 

 of the extinct mammalia. 



