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THE ESSEX FIELD CLUB.
Bivalve (Cyrena fluminalis) which still lived, but only in the Asiatic rivers and
the Nile. It was evident, therefore, that a great climatic change must have taken
place since the formation of these valley gravels, and a closer examination of the
river itself confirmed this view. At the bottom of the river Orwell they had what
was called a forest bed. : Such submarine forest beds were not uncommon over
the bottoms of the estuarine rivers of the country. There was another at the
mouth of the river Deben. In the valley of the Orwell from about a mile below
Pin Mill up to about a mile inland, there was a vast and uninterrupted bed of peat,
full of the recumbent trunks of trees, which formed the bed of the river. This
was about nine feet in thickness, and it rested upon a bed of marl, containing
freshwater shells, not a marine shell among them. The peat was crowded with
the leaves of poplar and willow and other marsh-loving plants. It contained an
abundance of hazel twigs, leaves, and nuts, some of the latter being so well
preserved that there could be seen upon them marks of the teeth of squirrels or
dormice. This peat bed could only have been formed when the land stood high,
and when, as the freshwater marl indicated, there was no marine connection at all
with the valley. At that time the river Gipping, as it was now called, must have
flowed right down past Harwich, through a marshy "Norfolk Broad" sort of
country, into the river Thames; the Thames made its way through a similar
district, to be eventually joined by the Rhine, and both of them fell over the great
precipice beyond the Dogger Bank, where they now found deep water of 100
fathoms all at once. When the river valley began to be formed, therefore,
England was not an island, but part of the continent, and separated from it by the
river Thames only, which flowed along the present Swin Channel—the latter was
still the great water highway for ships going north. In the history of these modern
Essex and Suffolk estuarine rivers, they had the last finishing touch given to the
geological history of the globe, long and continuous and sequent as they had
found it to be. There was no doubt that towards the close of the Glacial period
the valleys of the Gipping and the Orwell were filled, not with water, but with
moving ice. They learned this from many auxiliary facts. They found the
boulder clay often dragged down into the hollows from the high ground. During
the making of the new dock at Ipswich there were discovered magnificent masses
of Greywether stone, with mammilated surfaces, all grooved and striated in the
direction of the river. All this proved that during the Glacial period, and after
the land had ceased to be covered with ice except in the upper portions, the ice
still moved down the river valleys, and debouched into the German Ocean on the
right and left, leaving the bottom strewn with boulders to show that ice flowed
before water. Then these conditions changed. The climate altered sufficiently to
allow the warmth-loving shells to live in the larger valleys. It was a time when
the rainfall must have been so much more abundant than at present that Mr.
Tyler had called it the "Pluvial period," when the valley gravels were formed
under catastrophic climatic conditions. Hence it was that every one of our
English valleys was a world too wide for the rivers themselves. There was not
one of them in which the smallness of the river in comparison with the size of the
valley did not remind one of a little boy wearing his father's trousers, for they had
originally been the beds of rivers which could only have been supplied by a
continental, and not by an insular rainfall.
Dr. Taylor was warmly thanked for his address, and the steamer, it now
being half-past three, made its way towards Parkeston Quay. On the way
time was spent in the examination of a collection of fresh botanical specimens,