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beds there seems to be clear evidence of four successive stages of 
submergence, each distinguished from the other by different mineral 
conditions. The first bed, that in which the bones were entombed 
along with the human implements, indicates an action strong, if not 
violent, but not of long duration. The second indicates, by its finer 
materials, the action of a gentler force. The third seems to be 
very much a repetition of the first ; whilst the last can only be 
accounted for on the supposition that fine sediment had time to 
accumulate in comparatively tranquil waters. The interest of the 
question is very much centred in the nature of the action which 
began this series of events. Perhaps it may be well to look at the 
conclusion come to in respect to the origin of the mammaliferous drift- 
gravel by the geologist who has devoted most special attention to 
the subject, and before the discoveries of Abbeville had disturbed 
any preconceived idea. I find Mr Prestwich, in a lecture delivered 
in 1857, coming to this conclusion in respect to the ossiferous 
gravels of the Thames : — Taking into consideration the absence of 
contemporaneous marine remains, and noting the immense mass of 
but slightly worn debris derived from and covering irregularly the 
sedimentary deposits ; and the fact that it has evidently been trans- 
ported from greater or less distances, combined with the occurrence 
in the gravel of the remains of large land-animals, of trees, and of 
fresh-water land-shells, we have, I conceive, at all events in these 
facts, indications of at least one land-surface here destroyed, and 
its rocks, plants, and animals involved in one common wreck and 
ruin.” 
An able and elaborate paper on the u Distribution of the Flint- 
Drift of the South-east of England,” &c., was communicated to the 
Geological Society of London by Sir It. Murchison in 1851. The 
phenomena he describes seem everywhere to be a precise repetition 
of those of Abbeville. Everywhere the flint-drift, ■which is often, as 
there, covered by brick earth, clay, or loam, is characterised by the 
bones of the great extinct mammalia, and everywhere, according to 
the author’s view, gives evidence of sudden and violent diluvial 
action. Everywhere, also, this drift-gravel rises high above the 
levels of the existing drainage, whilst, at the same time, it gives 
evidence that the general configuration of the surface was substan- 
tially the same as now. Everywhere, also, wherever shells have 
been preserved, they belong to our existing fauna, and thus prove 
