Twenty one years after the hull
of the Mary Rose was brought to the surface, archaeologists are
again diving on the wreck-site. Their goal is to recover objects
left buried within the seabed outside the hull, together with
any remains of the hardware left over from the original excavation.
The seabed has changed in the 21
years. Over 50cms of sediment has accumulated over the site. All
of this has to be removed to find the evidence left over from
the excavation of 1979-1982.

To clear the sediment, divers are
using an underwater vehicle on wide rubber treads with a suction
pipe attached to it. This can be operated from the surface and
is used to remove the upper layers. This is similar to using a
JCB on a land excavation.
The objects within this layer are
mixed, which suggests that the seabed is being disturbed nearby
and is being redistributed over an area which includes the site.
The modern seabed is made up of slipper limpets and other shells,
like oyster shells, flints and coal within a very fine silt. This
layer contains a mixture of artefacts including nineteenth century
porcelain and a domino which is probably from the time of HMS
Victory. Because this is a mobile layer, we cannot date the objects
more exactly. Some items have been found which relate to the excavation
of 1979-82, including an on/off tap for one of our airlifts (still
numbered ‘port 7') and a white coffee mug.
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Artefacts and any significant features have their
positions fixed by placing an acoustic pole on top of them. This
sends signals to four acoustic transponders which have been placed
in the seabed around the site. These send signals to each other,
and the distance is computed from the time it takes to send and
receive the signal. The position of each of these has been fixed
in the world using the global positioning system available through
satellites. This system is also used to track the vehicle and divers.
All diving is undertaken using air supplied to
the diver down an umbilical from the surface. The umbilical also
has a communications and camera cable. This allows the diver to
talk to the surface, and people on the surface to see and record
what the diver sees. The divers descend to the wreck site using
a wet bell, which operates just like a lift, but also has its own
onboard emergency air supply, communications, cameras and lights.
Visibility is good, about two - three metres.
It is however difficult trying to recognise shapes beneath the covering
silt. The side of the hull hole is still a slope, but the middle
is full of a dark and menacing ooze made up of liquid mud and seaweed
to a depth of over a metre.
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