420 H. H. Howorth.—A Great Post- Glacial Flood. 
lowlands, especially in the valleys within 100 feet above the level of 
the sea, a wide spreading out of gravels that show signs of sudden 
and tumultuous deposition. Subaerial denudation could not produce 
the hill gravels containing rocks brought from a distance. Nor 
could the deposits lying on the sides of the valleys have been left 
there during their excavation; for, as we have seen, the configuration 
of the country dates back at least to early Tertiary times. Water 
must have been present to form the gravels of Dartmoor up to 
about 1200 feet above the sea, and also to allow ice to transport 
the erratic blocks (? about ice, H.H.H.). Was the water that of 
the ocean or of a great freshwater lake? With respect to the area 
in question there is this insuperable objection to the theory of 
marine submergence, that over the whole district no marine beach, 
and not a single marine organism, has. been found, excepting within 
a few feet of the present sea-level. Nor can sea-shells have once 
existed in the deposits, and been destroyed; for mammalian remains 
and land and fresh-water shells are preserved; and any agency that 
would have obliterated the one, would not have spared the others ” 
(Journ. Geol. Soc. vol. xxxii. pp. 83 and 84). Mr. Belt then proceeds 
to postulate his great European lake pounded back by an Atlantic 
elacier, which I have already examined in a former paper. The facts 
he condenses in the passage above quoted seem to me to be explain- 
able only by the wide-spread flood I have so frequently invoked. 
To continue, however. If we follow up these southern and transitional 
rolled gravels, we shall find as we have said the rolled pebbles 
gradually giving place to angular and subangular ones and, eventually, 
on reaching the Channel, we find at some points, as at Selsea, and 
the mouth of the Somme, the same collocation of ossiferous débris 
with marine shells like those in the adjoining sea, that we have in 
Yorkshire, and pointing the same moral of continuity. Now these 
angular drifts of the English Channel we have already devoted a 
paper to, and claim to have shown that they unmistakably evidence 
a great diluvial movement. 
We have thus glanced at the various deposits of rolled gravel 
found in England, and which bear superficially only a distant re- 
lationship to one another, and shown that they are continuous, and 
that they all bear consistent testimony to a great flood of water 
having distributed and arranged them as we now find them. 
If we leave England and travel elsewhere, we shall find the posi- 
tion here maintained largely supported. Thus, Sweden is a notable 
area in which very large districts are occupied by sands and gravels 
which were doubtless synchronous with the so-called Middle Sands 
and Gravels already discussed, since in them in certain limited 
localities, as near Upsala, we find testaceous remains which resemble 
those still existing in the adjoining seas. specially do these 
stretches of sand and gravel occur in the northern provinces of 
Sweden, those of Dalecarlia, Helsingland, and Jemtland. M. 
Durocher, a very competent observer, who had closely studied the 
problem on the spot, long ago said of these deposits, that they bear 
very evident traces of the action of water. ‘In many places, espe- 
