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have been cleared of the detritus that filled them in a comparatively limited 
period. Had such been the case, it would have destroyed the argument for 
the antiquity of man. I should be glad to hear from Professor Hughes 
whether, in his opinion, the land went down to a depth sufficient to allow 
of the water covering those spots where the implement-bearing gravels are 
now found. If it did not, then the falling and rising of the land, to my 
mind, gives no clue to the age of the river deposits. But are these 
gravels really river deposits ? This is the point which the Duke of Argyll 
is inclined to dispute. There are two or three reasons why I doubt these 
gravels being river deposits, and one is the height at which they are found. 
They are not merely in patches on the slopes of the valley, but are spread 
on the highest ground of the Somme Valley, — a condition of things which, 
it appears to me, difficult to understand ; for I cannot see how the river 
Somme could have deposited these gravels at such heights. Another ques- 
tion arises, how came the flints shattered ? the slow movement of the water 
from the very small fall it had at that time, not amounting to so much as 
2 feet in a mile, could not have done it. I should not have expected to find 
flints in this condition [producing them], simply from gradual river erosion. 
Mr. S. R. Pattison, F.G.S. — I think the paper read by Professor Hughes 
has been most exhaustive of the whole subject. With the motives of true 
science he has abstained from drawing deductions which the facts did not 
allow of finding ; and I suppose that although we should all have been very 
glad indeed to have had the correlation of the river-gravels with any of those 
gravels which have been mentioned to-night, yet he has resolved that ques- 
tion by reference to what he supposes to have happened during the retreat 
of the glaciers. Beyond this I think he has not led us, nor did his paper 
profess to do so. I suppose that enjoyment is to be deferred to some future 
time. We have been many years pulling down old theories and turning 
opinion to the Glacial period, and probably at some more modern time we 
may be pulling down the Glacial theory. But I should be very sorry to 
attempt to lay any crude speculations before the Society, especially in the 
face of a paper so full of facts as that which we have heard to-night. 
Professor Hughes. — I think I must pass by some of the questions that have 
been raised, as they wander a little beyond the subject which we have been 
discussing. With regard to the age of the Thames deposits as compared with 
those of Moel Tryfaen, the point which I wish clearly to bring out is this : that 
after the close of the cold period the ice was lifted off by submergence of the 
land, and our story begins when the land came up again. In the earlier deposits, 
of course, the shells and the various other organisms, show that the arctic 
forms had not all gone away. In the later deposits we have more and more 
southern forms. It was in this post-Glacial period that the Thames Valley 
received the deposits which we find in it. The included remains show that 
these deposits are fluviatile or estuarine. With regard to the many remarks 
and ingenious theories which have been brought forward by the second 
speaker, it is perfectly true that a deluge is not impossible ; but the 
question as to whether on examining the surface of the earth you have 
