The Comacchio wreck
Fede Berti
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The find location
The Roman ship of Comacchio was discovered on the city outskirts near
the initial section of the Water Collection Canal, the principal
drainage channel of the Valle Ponti basin which was reclaimed between
1919 and 1922. The first clues of the vessel’s presence were revealed in the fall
of 1980 (signalled by the Comacchio Archaeological Group) when, during
dredging operations in the canal, several timber fragments -- later
identified as belonging to a vessel -- came to the surface.
The entire upper portion of the wreck was brought to light and
the cargo recovered during an extensive excavation season in the summer
of 1981. Subsequently, the vessel was submerged beneath the watertable
in order to preserve the timber pieces.
Excavation and recovery of the hull
The internal planking and frames were removed between the end of the
autumn of 1986 and the winter of 1987, while the hull planks and
futtocks of the port side were left in place.
The recovery took place during the winter of 1988-89. The hull,
supported by a wooden cradle adapted to the structure’s distortions and
encased within a metallic framework, was raised and transported to the
interior of the
Palazzo Bellini complex at Comacchio.
The conservation treatment
Initially the vessel was positioned within a tank measuring 25 m. in
length, 6 m. in width and 3 m. in height; once freed from its metal
framework, it underwent repeated rinses. It was immersed in fresh water
together with the internal timber elements. Recently a fibreglass case
was custom-built to fit the hull, in accordance with a project designed
by Costantino Meucci of the Istituto Centrale del Restauro of Rome, in
order to reduce the amount of PEG necessary for the conservation
treatment as well as to significantly lower its costs and duration.
The environmental context and shipwreck dynamics
The ship ended its voyage on a poorly populated beach near a river
mouth. The vessel, pushed by the wind and currents, most likely during a
sea storm, was beached near the waterline. The superstructures were
destroyed by waves which underwashed the vessel at its base and thus
caused it to sink into the sand, aggravated by the considerable weight
of the cargo. In a short time, the vessel was covered by beach
sediments.
Description of the hull
The state of preservation
The hull is preserved over a length of little more than 20 m. Part of
the port side is still connected to the stern gripe up to the wale,
while towards the bow (identified thanks to the presence of an anchor)
the planking strakes are detached and overlapping. The bow and the
adjacent sector, as well as the starboard side, are missing. A crack
splits the planking near the stern gripe.
The keel
The vessel, lacking a proper keel, featured a keel plank. A stern gripe
(which survives) and another linking element towards the bow were
attached to this keel plank by diagonal scarfs.
The stern gripe was made from a massive block of elm, measuring 1.7 m. in
length and with a rather complex profile. Foreward, the block
measures 35/32 cm. in thickness and 34/32 in width, and has a polygonal
profile (decahedron). The upper extremity was attached to the
sternpost (which did not survive) by means of a hook scarf.
Furthermore, at 20 cm. from this end, the gripe is pierced by a
transversal square-sectioned hole, in which there is a holm oak pivot or
bolt. The hole, although displaying no signs of wear, perhaps
constituted part of a towing system. Moving towards the bow, the gripe
broadens and thickens to 20 cm., becoming trapezoidal in section and
internally hollowed. Farther along, in relation to the first diagonal
scarf (at ca. 3.7 m.), the thickness tapers to 5 cm. in order for it to
join the keel plank, which measures 12.12 m. in length.
A diagonal scarf connects the keel plank to another element of which
only an 1.82 m. portion survives. Trapezoidal in section, it measures
20 cm. in width on its upper face and 11.5 cm. on its lower surface,
with a thickness of 7 cm.
The plank ends are nailed to the stern gripe, while the garboard strake
is attached to the keel plank by means of stitching.
The planking
The hull structure is composed of elm planking joined by diagonal scarfs
fixed with horizontal iron nails. The width of the ceiling planks
ranges from 17 to 29 cm. while their thickness averages 5 cm.
The quick work is assembled by lashed joinery. Diagonal holes are cut
within the plank thicknesses at about 4 cm. from the edge and at
intervals of 6-8 cm.; these holes come out in correspondence with the
external edge of the plank surface where there are small rectangular
cavities measuring 1.8 by 1.5 cm.
The caulking, which is placed within
the joint and consists of lime fibres, is covered by wool cloth and
fixed by four esparto cords, passed through together transversally and
then split and interlaced. The holes are closed by pegs made of various
wood types (ash, cornel and lime). The caulking displays traces of
pitch.
A 7-cm.-wide wale, attached to the hull by pegged tenons of holm oak,
survives along the port side. The mortises are 8 cm. wide and 0.5 cm.
thick, spaced at about 12.5 cm. intervals and slightly staggered.
The frames
The framing system consists of oak floors and futtocks.
The average floor spacing is 45 cm. At midships a broader spacing (60
cm.) forms a sort of transversal corridor.
The floors are rectangular in cross-section (16 cm. moulded, 12 cm.
sided) and, on their lower face, feature ca. 10-cm.-wide rectangular
grooves to take the caulking material. The mortises become trapezoidal
at the height of the bilge.
There is a central limber hole.
The nineteen surviving futtocks are inserted in the intervals between
the floors at the turn of the bilge.
The frames are attached to the hull by five pairs of esparto plaits. In
correspondence with the edges, a plait fixed with a knot the remaining
plaits, which passed in pairs through apposite holes in the planks and
were themselved fixed by pegs.
The plaits were tilted away from the
centre line in order to avoid slippage due to tension.
The two floors (17 and 18) flanking the transversal corridor feature
several cavities to take the deck stanchions. They are spaced at about
80 cm. from each other. Other mortises are found on floors 4, 11, 16
and 32.
The internal planking
The internal planking is composed of various pieces of ceiling planking
and several stringers, surviving only along the port side. The wood
utilised is walnut, elm and oak. The seven stringers are nailed to the
futtocks and feature square recesses for the upper beams.
The ceiling planking, in four sections, is constituted by planks that
measure 2 cm. in thickness and which in length measure, respectively,
starting from the stern: 3 m., 5.85 m., 5.9 m. and 2 m.
The first portion of ceiling, made up of nine planks, features a series
of engraved Roman numerals from VI to XIV. These are identifying signs
in the case that the planks were to be disassembled, for repairs or to
clean the hull, and then replaced in sequence. Only the central plank,
n. XIV, was fixed to the structures, while the others were simply laid
on top.
Another portion of ceiling, attached by means of lashings and
trapezoidal in shape (length: 2.32 m.; width lower base: 74 cm.; width
upper base: 1.25 cm.), was found beyond the starboard side near the
stern gripe. It has been hypothesised that this was a roof cover for a
hatch.
Reconstruction of the hull: form and function of the vessel
Marco Bonino has reconstructed a decked vessel with a square sail and
side rudders. At the stern, the deck was broader while the galley must
have featured a raised roof covered with tiles; in front of this there
was a trapezoidal hatch, probably with a roof cover. A hatch was likely
located at midships and another wider one at the bow.
The vessel, with a flat and rounded hull, must have measured over 21
meters in length and 5.62 m. in width, and must have weighed, when fully
loaded, 130 tons. The absence of a real and proper keel made this a
vessel adapted both to internal and coastal navigation.
The cargo and the date of the vessel
The variety and rarity of the materials transported by the vessel make
this one of the most significant discoveries ever made in the Ferrara
delta. They reflect the complexity and liveliness of commercial
contacts which were redistributed within the Po valley plain along the
Po River, and allow a dating of the wreck to the end of the first
century B.C.
The primary cargo consisted of 102 lead massae of Spanish origin,
amphoras for food transport and boxwood logs. The ingots are marked
with a series of stamps, among which the name Agrippa occurs regularly.
North Italic sigillata pottery was also carried on board, as well as six
tiny lead foil votive temples. Among the heterogeneous material
belonging to the ship supplies were a bronze balance with which to sell
merchandise by retail, numerous items of clothing, containers and
leather shoes belonging to the crew and passengers, as well as a series
of ship maintenance tools (mallets, an axe, a plane) and for the
vessel’s steering (sheave blocks, a boat bailer, an iron anchor).
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