While the Mary Rose project is a full time job for our conservation team, they still find time to help others who require the assistance of expert maritime conservators.
Mary Rose Archaeological Services (MRAS) have worked on many projects over the years, one of the most recent was the Bell of HMS Hood, on display in 36 Hours: Jutland 1916, The Battle That Won The War at the National Museum of the Royal Navy in Portsmouth Historic Dockyard.
Photograph by Allan C. Green, Restoration by Adam Cuerden
HMS Hood was ordered in mid-1916 and construction began in September. Her design was quickly modified to take account of the devastating losses suffered by British battle cruisers at Jutland and over 5,000 tons of armour was added to her hull. Launched in 1918, her career spanned 23 years before she was sunk on 24th May 1941 by the German battleship Bismarck during the Battle of the Denmark Strait. Only three men, out of a crew of 1,418, survived.
In 2001 the wreck was located by Blue Water Recoveries, with the ship’s bell found lying on the seabed away from the hull. Paul G. Allen (co-founder of Microsoft) led an expedition, supported by Blue Water Recoveries, in August 2015 to retrieve the bell and soon afterwards it was sent to MRAS for conservation treatment.
In October that year the bell was x-rayed by 1710 Naval Air Squadron with the assistance of Mary Rose Conservators. By x-raying the bell, our Conservators could locate any defects or fractures which would cause problems with structural integrity or corrosion. To understand if it would be possible to hang the bell, it was important to know if it could take the stress. They were also trying to determine, using the x-rays, if the inscription around the bottom of the bell was cast at the same time as the rest of the bell.
The x-rays showed that the main body of the bell was structurally sound as it didn’t have any fractures or cracks, but they couldn’t prove if the inscription was original or a later addition. However, x-rays of the loops, or cannons (from which the bell hung) did produce surprising results as they revealed that two of the loops had actually been added after the initial casting, something that had previously not been suspected! Three joints were visible in the x-rays, showing that the loops were made up of two separate sections of different densities.
Our conservators also wanted to discover which elements were present in the bell to determine the best course of treatment. To do this, they used a handheld X-ray Fluorescence Spectrometer (XRF) from Oxford Instruments. This device can register the elements present within an item in seconds and without causing damage.
Results from the main body of the bell showed it had a high percentage of copper (82%) and tin (13%), as expected from an item made of bronze, with a few trace elements such as silver and sulphur.
As there was some discussion concerning whether or not the inscription around the base of bell was added after the bell was cast, one of the letters was also analysed. The percentage of copper in a ‘B’ from the inscription was only 73% and it also contained traces of elements not present in the main body, such as lead and arsenic. These differences were felt to support the hypothesis that the text was cast separately to the bell.
After examination by our experts, it was decided that it only needed surface treatment – the Mary Rose’s collection demonstrates how well bronze can survive under the sea! Our conservator, Sue Bickerton, used mechanical cleaning techniques to remove encrusted detritus and prepare the bell for display.
We are also looking to work Micropasts to create a pre and post conservation 3D model of the bell.
The bell was presented to the HMS Hood when she was launched in 1918, by the widow of Rear-Admiral Sir Horace Hood, great-great grandson of Sir Samuel Hood after whom the ship was named. Sir Horace died at the Battle of Jutland on 31 May 1916, one of 1,026 officers and men who died in seconds when the battlecruiser HMS Invincible blew up and sank, and the bell is inscribed to that effect.
The bell of HMS Hood is now on display in a new exhibition 36 Hours: Jutland 1916, The Battle That Won The War at the National Museum of the Royal Navy in Portsmouth Historic Dockyard. The bell has been installed as a memorial to the 1,415 men who lost their lives when the ship sunk in 1941.