UKDIVING
of the torpedo range there. A hurricane swept through the Channel, and either her tow broke or it was cut as 30 men were taken off her. Enterprise boldly went to the harbour, while Mooring Lighter No. 8 sank.
For 47 years she was known as the Yard Craft or Mooring Lighter No. 8, but in her afterlife was nicknamed Pin Wreck by divers pillaging her for scrap metal. We think it’ s time to give this vessel her identity back.
Last year we spent a few days in Greenwich, having found some correspondence which was‘ hidden’ in the catalogue. We had confirmation that this barge was built at Portsmouth Dockyard in 1866, a replacement for a previous Mooring Lighter No. 8, which was decommissioned. The Admiralty at the time were insisting all vessels in the dockyards were called‘ Yard Craft’ with a reference number, whatever their function. We also found Parliamentary Papers which revealed she cost £ 6,121, about £ 930,000 in today’ s money.
Photogrammetry by Martin Openshaw
The wreck today
There are drawings of similar mooring lighters in the plans section of the National Maritime Museum, but not of this vessel. Martin is redrawing some key parts of her by using photogrammetry in combination with a 3D CAD system. The wreck is 24 metres long and 7.2 metres wide.
The main feature of the wreck is the capstan winch, standing at least 2.5 metres
Boiler water pump flywheel
42
from the seabed. This was powered by a small single cylinder engine also equipped with a small capstan for lifting cargo into and out of the hold. The engine seems to be the home of a very friendly conger, which is often free swimming. The boiler for the engine is on the opposite( port) side of the vessel. It is possible to swim under the winch between the gears, but bear in mind that the worm wheel alone weighs three tonnes and the shaft it sits on is eroding.
The winch is an important feature, given that the first-steam driven capstan winch was installed on HMS Black Prince( sister of
" The engine seems to be home to a very friendly conger eel "
SHEILAH OPENSHAW the Warrior) in 1861. In 1866 Mooring Lighter No. 8 was installed with cutting edge technology; as yet we do not know who actually made the winch, but it could be that it was Brown & Harfield.
There are two mooring buoys in what would have been the hold, often mistaken for boilers because they are cylindrical. A huge pile of chain and shackles is located between the boilers and the buoys. This could either have been
associated with how the vessel lifted stuff on and off the seabed, or it may have been how the mooring buoys would have been anchored to the seabed. Or it may simply have been stuff which was put on the vessel for transportation to Portland from Portsmouth.
There is a wheel between the boiler and the chain. Recent investigation indicates this is probably the flywheel for the pump feeding the engine with water. There are a number of anchors around the wreck. Further investigation will reveal if they are anchors to stabilise the vessel when working or the weights for the mooring buoys.
Today, the wreck provides a focal point for research into the engineering and working practices of the mid-1800s. It is a fascinating dive, offering a glimpse into the massive engineering of the Victorian period; though it’ s unlikely we’ ll learn more from the wreck itself. After 120 years on the seabed, concretion hides the details and the underlying iron is in a fragile state because of corrosion. Nevertheless, identifying the vessel does provide a thread into the archives where more information may reveal the long-forgotten details of her design, construction and use. �