FOWLNESS.
241
occurring at Shelford, within the walls of the island, but it covers no
great area.
On the north of the Crouch a nearly continuous bank of similar
shell extends by Coney Hall, Mount Sales, &c., to Bradwell. The
shells appear to be of the same species as those in the present shell-
beaches in the neighbourhood. This I hope to describe to you on
some future occasion.
As is usual in estuary deposits, the channels of the rivers Roach
and Broomhill have frequently changed during the formation of
Fowlness, either naturally or compelled by man to do so.
Fowlness, we find, is composed of several smaller islands, the
creeks separating which have been filled up, and the streams that
flowed in them diverted into other channels.
It is possible, in places, to trace the boundaries of the component
islands; for in some cases the old sea-walls remain, and the main
thoroughfares of the island have been made along old walls, so that
the roads are the boundaries, in a great measure, of the former
islands. In some parts the old walls mark, not the boundaries of
former separate islands, but the increase of one island by taking in
more saltings.
Thus along the Sands from Shelford to Fisherman's Head is a strip
of about 300 yards in width, added since the main body of the island
was first enclosed. In like manner, all the east end of the island, from
Court's End to Fowlness Point, is of more recent enclosure than the
bulk of the island.
About half a mile east of the Quay Farm are some remains of an
old sea-wall, in which a brickfield has been opened and a kiln
erected. The clay used in making the bricks was dug directly under
the old wall. It is a fine, clean clay, with sand partings dividing it
into laminae, varying from one-eighth to one inch in the thickness.
No trace of shells has rewarded the most careful search.
This deposit was evidently laid down in standing water, into which
clay and sand were alternately brought. Had any vegetation been
present, the regularity of the laminae must have been destroyed
thereby. I believe the land east of this to be as old as any in the
island, and that on the west up to the Quay Reach to be consider-
ably more recent. Immediately outside this wall, to the west, there
lies under the. soil a thick bed of blue silt, which suggests the
presence here of the earlier representative of the Quay Reach.
Whilst the surface, like that of most alluvial deposits, is for the