s that lie below the level of the sea, being protected by
embankments. Some of the fens were embanked and drained by the Romans;
but after their departure the sea returned, and large tracts were
covered with beds of silt, containing marine shells, now again converted
into productive lands. Many dreadful catastrophes are recorded by
incursions of the sea, whereby several parishes have been at different
times overwhelmed.

_Norfolk._--The decay of the cliffs of Norfolk and Suffolk is incessant.
At Hunstanton, on the north, the undermining of the lower arenaceous
beds at the foot of the cliff, causes masses of red and white chalk to
be precipitated from above. Between Hunstanton and Weybourne, low hills,
or dunes, of blown sand, are formed along the shore, from fifty to sixty
feet high. They are composed of dry sand, bound in a compact mass by the
long creeping roots of the plant called Marram (_Arundo arenaria_). Such
is the present set of the tides, that the harbors of Clay, Wells, and
other places are securely defended by these barriers; affording a clear
proof that it is not the strength of the material at particular points
that determines whether the sea shall be progressive or stationary, but
the general contour of the coast.

The waves constantly undermine the low chalk cliffs, covered with sand
and clay, between Weybourne and Sherringham, a certain portion of them
being annually removed. At the latter town I ascertained, in 1829, some
facts which throw light on the rate at which the sea gains upon the
land. It was computed, when the present inn was built, in 1805, that it
would require seventy years for the sea to reach the spot: the mean loss
of land being calculated, from previous observations, to be somewhat
less than one yard, annually. The distance between the house and the sea
was fifty yards; but no allowance was made for the slope of the ground
being _from_ the sea, in consequence of which the waste was naturally
accelerated every year, as the cliff grew lower, there being at each
succeeding period less matter to remove when portions of equal area fell
down. Between the years 1824 and 1829, no less than seventeen yards were
swept away, and only a small garden was then left between the building
and the sea. There was, in 1829, a depth of twenty feet (sufficient to
float a frigate) at one point in the harbor of that port, where, only
forty-eight years before, there stood a cliff fifty feet high, with
houses