418 H. H. Howorth—A Great Post-Glacial Flood. 
period (? interglacial, H. H. H.) would be much eroded and their 
materials reconstructed and huddled together, while whatever lay 
loose at the surface, whether on hill top, hill side, or valley bottom, 
would be swept on so as to mingle with the heterogeneous detritus 
carried forward by the floods” (id. p. 584). 
Mr. Searles V. Wood, who has done so much work in the elucidation 
of the surface geology of Eastern England, is also constrained to 
invoke torrents of water to explain the distribution of the so-called 
Cannon Shot Gravel of Hast Anglia; ‘“ consisting for the most part of 
thick beds of flints rolled into the shape and dimensions of the 
now obsolete cannon shot of from 12 to 32 lbs. calibre.” This he 
attributes to “some local modification of the chalky clay formation 
by powerful currents, for he says he sometimes found imbedded in 
the gravels heaps of sand formed almost wholly of chalk grains” 
(Journ. Geol. Soc. vol. xxxvi. p. 500). He adds as his view that 
“torrents of water by their torrential character washed out much of 
the chalky clay in the valley of the Wensum and rolled the great 
flints in it, into the cannon shot shape.” This gravel gradually 
changes its character as we go eastwards and southwards, becomes 
finer, the great spherical flints become fewer, and in this finer form 
spreads widely over South-western Norfolk and North-west Suffolk,” 
covering the paleolithic brick-earths at Hoxne, Brandon, and 
Mildenhall. From Hoxne the bed increases in thickness and often 
becomes a thick deposit of only sand which stretches northward and 
inosculates with the cannon shot form. Mr. Wood, speaking of the 
loose sheets of surface deposits in East Anglia, refers to “ these 
volumes of water pouring over Norfolk.” Again, “The gravel 
which it (i.e. the water) produced by washing out the moraine and 
the large flints which by its torrential force it rolled into the cannon 
shot form described, were thus left on the plateaux and brows of the 
valleys, the largest stones nearest the water source, and the smaller 
stones and sand carried furthest..... This water denuded the 
Hoxne brick-earth, forming or enlarging in so doing the lateral 
valley of the Gold-brook; and as it sank away it left the thin 
wrapper formed of gravelly sand which it carried over the denuded 
surface of the brick-earth” (id. pp. 501 and 502). This seems to me 
most reasonable. What I object to is the theory which deduces 
these floods from the melting of the ice-sheet, which I have already 
criticized. So much for the lessons taught us by the ossiferous 
gravels. 
Let us now pass on. We have traced a continuity from the 
marine drifts on the Welsh hills through the so-called middle sands 
and gravels and the barren inland gravels to the ossiferous deposits 
of Southern and Eastern England. This continuity is shown to be 
complete in every detail. When we turn to many of these latter beds 
in Yorkshire and Hast Anglia, we find them containing marine shells 
and debris of a similar facies, and therefore of the same geological 
horizon as those at Blackpool and Moel Tryfaen. This is familiar 
enough. This mixture is well exhibited in the well-known Hessle 
beds of the Yorkshire coast, and in the gravels of the Fen districts. 
