The remains of the wreck of a British Third Rate ship of the line, HMS Invincible, which stranded and capsized on the Horse and Dean Sand on departing St. Helen's for Louisburg, Canada in 1758. This wooden sailing vessel was built in 1744 and captured from the French in 1747 at Cape Finisterre. When in French hands she was called L'Invincible.
Built for the French navy in 1744, L'Invincible was captured by Admiral Anson at Cap Finistère, in 1747. Study of the vessel's design gave rise to the very successful 74-gun frigate class of the Royal Navy, and as such she has a very important place in its history.
She was lost in 1758, when her rudder jammed and she failed to clear the Horse Tail sandbank in the Eastern Solent. Flooding was controlled until, in worsening weather, she was driven further on to the sandbank, two of her pumps broke and her hold flooded immediately. Stores and guns were transferred to hoys to lighten her, and by the third day all four chain pumps had broken. In deteriorating weather she rolled over onto her beam-ends and was completely wrecked.
Designation Order: (No 2), No 1307, 1980
Made: 1st September 1980
Laid before Parliament: 9th September 1980
Coming into force: 30th September 1980
Protected area: 100 metres within 50 44.34 N 01 02.23 W
No part of the restricted area lies above the high-water mark of ordinary spring tides.
Built at Rochefort 1744 and captured from the French at Cape Finisterre in 1747, L'Invincible was taken into the Royal Navy. On the 19th February 1758 as part of a fleet ordered to sail for Canada where she was to assist in the routing of the French, the order to weigh anchor was given. In raising her anchor she first refused to break free, but on getting free her hawser got stuck on the wrong side of the bow and could not be catted. In attempting to get clear, the ship's rudder became jammed and she ran aground on Horse Tail Sand. Efforts were made over the next two days to free her, including the use of kedge anchors, lightening ship and spreading more sail in an effort to drive her off the bank, but all failed. On the morning of the 21st February the weather worsened and she commenced pounding on the sandbank and later that morning capsized, filled with water and was abandoned.
The Court of Enquiry began in March 1758 on board the Royal George. 'The principals examined were the pilots, who made it appear that it was no misconduct in the master, for had the ship been their own they should have behaved just as he had done, whereupon the master was set at liberty.'
The date of the wreck indicated the Invincible but some records showed that the Invincible was lost off the Owers, and her armament was 18 pdrs, not 24pdrs. However, a letter from the Office of Ordnance dated 23.12.1755 in the Priddy's Hard archive showed that the 18pdrs were replaced by the 24pdrs, and the court martial transcript located the place of loss to the Horse and Dean Sands. A wooden tally stick found on the site with the words "INVINCIBLE Flying Jib 26 x 26 No.6" appears to confirm the identity of the vessel.
On the 5th May 1979, the remains of the vessel were found by a local Eastney fisherman when trawling off Portsmouth: an old piece of timber with a treenail was recovered, possibly exposed by the general lowering of the seabed by gravel dredgers. The fisherman returned to the site with two local divers who worked the site all summer raising various artefacts.
Lying on a sandbank of fine to medium grain sand and susceptible to seaweed cover, a pre-disturbance survey and attempt to identify this site was undertaken in 1980. Near the surface nine, 24, and 32pdr guns of a date prior to 1760, with rammer heads for 8 and 24pdrs, tampions and a cartridge pouch with a "G2" crown indicating George II were recorded.
The ship is now known to lie on her starboard side at an angle of 46 degrees and this portion of the hull is intact although she appears to have broken her back at the 64/65 frame. The wreck lies on the relatively flat, featureless bank known as the Horse Tail Sand, and the free running seawater leads to mobile sand and regular reductions in seabed level. The depth of the site is generally 6 to 7 metres. Part of the starboard side may be present in nearby wreckage. Sandglasses, a bronze adze and cooper's setter used to open barrels, and cartridge cases have been recovered from the site as have army buttons from 13 different regiments.
The remains are extensive and generally protrude less than 1 metre above the seabed. A feature which once stood 2 metres proud of the seabed, thought to have been the sternpost, was noted to be missing in 1998. In an adjacent area of the stern exposed timbers have been truncated, thought to have been by the MV Amer Ved which ran aground on the same sand in 1997, but there is no obvious sign of impact fracturing or splintering. This type of collision is a rare occurrence and not to be taken as constituting a significant threat. However, there is an extensive area of coherent vessel structure remaining exposed to the detrimental effects of free-running seawater, which may constitute the main threat to the long-term survival of the site. One possible strategy might be to stabilise and protect selected features considered to be of particular importance.
Magnetometer readings indicate that some cannon lie 200 metres to the south, confirming that the quarterdeck cannon were jettisoned when the vessel stranded.