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DAGENHAM BREACH.
By WALTER CROUCH, F.Z.S. (Vice-President).
[Read at Field Meeting, 23rd July, 1892.]
IT is almost impossible to realise what was the original course and
extent of the great Estuary which has at last dwindled down
into the waters which now form the River Thames.
In remote ages was deposited from an ancient sea some 600 feet
of chalk. On this, from a shallower sea, or broad estuary, the deposit
River Wall and Lake. Dagenham.
By Edmund M. Wimperis, after a sketch by Dr. Smiles.
of the London Clay was formed, until in historic times we find the
present river; flowing eastward from Thames Head,1 near Cirencester,
some 160 miles to Teddington (? Tide-end-ton), and thence, as a
tidal river, down to the German Ocean. The Basin, or depression,
through which it flows, drains "a very large tract, extending over
6,160 square miles, in fact, more than one-seventh of all England."2
1 This is but one of the many sources, which meet together at Lechlade, Gloucestershire.
2 Huxley: "Physiography," 1881. p. 16.
M 2