XI.
stools have been let down from a higher level by the
removal from below them of incoherent beds- a pro-
cess which in the Stour estuary is depositing tree-
stools in the position of growth on the alluvial flats
below high-water mark.
The marsh land on the River Colne below Wyven-
hoe is in some places below the low-water level of the
river, and when flooded by an unusually high tide
requires to be drained by steam-power. This may be
due partly to shrinkage as mentioned above (although
the meadows are constantly in a state approaching
saturation), or it may be due to the deposition of mud
in the bed of the river, consequent on the supply of
sewage from Colchester.
At the part of Colchester called the Hythe (i.e.
Wharf) the Colne is navigable at high water, and
granaries. &c, constructed on its banks 200 years ago
are now frequently flooded in the basement by high
tides. Any slipping, such as I have suggested for
Walton, is here disproved by the existence of artesian
wells extending deep into the chalk. An utterly im-
perceptible slip would certainly shear off a three-inch
bore-hole.
In a creek near Steeple, east of Maldon, a certain
row of piles, the top of which used 60 years ago to
be just uncovered at high water, are now covered
about 18 inches deep at most tides.
On the South side of the Blackwater, the hills come
down in a point to high-water mark at the old Roman
and Saxon station of Othonia or Ithanceastre, the
ruins of which are exposed on the beach. The tidal
slope is about a mile and a quarter wide, and on the
outer edge of this—an almost impassable bed of mud
—there are other ruins, visible at dead low-water
after storms have removed the sand and mud, and
consisting of foundations, wells, &c, the arrangement
of which is perfectly plain at such times. Alluvium is
now being deposited between these ruins and the main
land, so that if it is a case of denudation since the
erection of the buildings, the currents must have
altered considerably.
North of the Crouch the alluvium is 80 feet deep ;
on Fowlness and westward it is about 30 or 40, in-
dicating the existence of the Crouch Valley at a time
when the land was at least 40 feet above its present
level. Fowlness, a wholly alluvial island, has certainly
been stationary since the Norman Conquest, so that
any movement which may be in progress does not
include that area.
Antiquity of Man in Essex.
Our district has had the exceptional good fortune to
yield what is probably the earliest proof extant of the
advent of Man upon earth. Before describing the