THE "RED-HILLS " OF CANVEY ISLAND. 271
the first century A.D., or possibly earlier. The burnt earth contained,
in addition, the half of a silver penny of the period Henry II. to Henry HI.
and fragments of pottery of the 17th and 18th centuries, which affords
a further link with the. Mediaeval and Dutch periods in the history of
Canvey Island.
At Blackmore Avenue two further holes were dug of standard size
(6 ft. to 7 ft. long by 3 ft. to 21/2 ft. wide). Both yielded results of special
interest, namely, the presence of two layers of burnt earth containing
Romano-British and crude ware fragments of the usual character, separated
—at about 3 ft. depth below the surface—by a layer of "clay" 5 in.
to 10 in. thick, and containing—in one case—2 per cent. sand, and in the
other 17 per cent. sand. No shells were present in these layers, but
one of the layers adjoined a bed of fine particles of "clay," burnt red,
7 in. thick, and a layer consisting of clay and fine particles of chalk.
The thick intercalary layers may possibly have been originally domestic,
or industrial "floors," laid down on an uneven, friable surface of burnt
earth, at some intermediate period of occupation. The chalk may have
been used in the manufacture of crude pottery; small pieces of chalk are
frequently met with in the burnt earth of the mound.
At one of the two holes the burnt earth, at a depth of 5 ft. below the
surface, yielded a small rectangular block of crude manufacture, 31/2 in.
x 3 in. x 1 in. thick, worn at both ends. The object may have served as a
tool for moulding flat objects (c.f. Swinnerton, Ibid.).
At Ferndale Crescent, in a garden adjoining site "DI." described
p. 152 of last year's paper,1 the owner dug up a Samian base bearing the
name paterclinus, a manufacturer of Lezoux in the period Hadrian-
Antonine (117-138 A.D.), which confirms the date yielded by an earlier
moulded base, found last year.
The point arises, are the Red-hill mounds of Canvey Island outliers
of the old land surface of the Mainland opposite, which is characterised
by deposits of brick-earth of somewhat similar composition to that of the
sandy loam located at the Red-hill mounds, or were they originally banks
of estuarine deposits thrown up locally by the tides at a period anterior
to that of the Romano-British occupation?
The geological evidence relating to this subject is discussed in a
paper that has been submitted for publication elsewhere, and only a
brief summary of the facts can be given here, but it may be stated with
confidence that the mounds are the result of industrial and domestic
operations that utilised material accumulated by tidal action in the
Estuary. Briefly stated, it is found :—
1. That the few shells—all edible forms—recovered from the burnt
earth and subsoil of the mounds are of estuarine character, the species
being identical with those found living in the Estuary today.
2. That deep well-borings made at a number of points in the island
—some of them in the neighbourhood of the Red-hill mounds—indicate
that the subsoil to a depth of 70-80 feet consists of river deposits and
river gravel resting on a base layer of London Clay, and that the sandy
loam located at the mounds rests on a subsoil of river deposits—sand
and silt—and not directly on the London Clay itself.