bs_bs_bannerbs_bs_banner The International Journal of Nautical Archaeology (2018) 47.2: 460–471 doi: 10.1111/1095-9270.12299 Note Copper and Muntz Metal Sheathing: a global update n earlier article published in this journal It is now clear that before precise chemical analysis that examined copper and other sheathing existed in the second half of the 20th century, the A in the Royal Navy in the late 18th, 19th Admiralty had no understanding why some copper and 20th centuries prompted worldwide interest was good while apparently similar copper was bad. in this previously little-investigated subject. It To establish the difference between the good and included a catalogue of sheathing stamps that indicate bad coppers, the Admiralty dated all ships’ copper manufacturer, application date, dockyard, Admiralty sheathing to know how long it remained serviceable by inspectors’ marks and Government broad arrows, identifying the dockyard, manufacturer and the date and sheet weights recovered from HMS Pomone, of coppering. To-date, no one has come up with an HMS Victory,HMSTincomalee, and HMS Maeander alternative explanation as to why each copper sheet was (Bingeman et al., 2000: 218–229). While the original dated on all Royal Naval ships. article concentrated on examples from Royal Naval warships, this update, while including warship sites, is mainly devoted to non-warships. Muntz metal, Royal naval ships a 60:40% copper-zinc metal patented in 1832, with In the late 18th century and in the early years of the slightly varying ratios entirely superseded copper 19th century, the British Admiralty continued to buy sheathing in the merchant service (Percy, 1861: 619). in sheathing from the Mines Royal Company until the While recorded sheathing marks cover only a fraction Portsmouth Rolling Mill was built 1804–06 (NMM, of marks used in the 18th and 19th centuries, this 1804). At the time, the Admiralty had a large stock of article incorporates further examples by introducing used copper sheathing that needed recycling. Current countermarked coins that more than double previously research found the latest use of Mines Royal copper known marks. These countermarked coins represent was on the 64-gun Agamemnon wrecked in Maldonado marks that were applied to numerous copper sheets Bay, Uruguay, at the entrance to the River Plate on 16 during the course of naval ship building (Bingeman June 1809, which had been re-coppered at Chatham et al., 2000: 227). Dockyard in ‘JAN 1807’ (Fig. 1a, Table 1) and the The question has been asked why the Admiralty sheathing displayed the mark ‘MR 28’, indicating the required every copper sheet to show its month and use of 28oz per square foot plate (Fig. 1b-c). year (Bingeman et al., 2000: 223). In his lecture to The 38-gun Pomone wrecked at the Needles, Isle of the Institution of Naval Architects in 1863, W.J. Hay, Wight, 14 October 1811, bore a similar Mines Royal Admiralty Chemist and Lecturer at the Royal College, Company sheathing mark of ‘MR 32’ (Fig. 1d). It Portsmouth, clearly identified the problem they were is assumed that Pomone was coppered with sheets trying to solve in the late 18th century: why was some supplied by Chatham Dockyard due to the presence of copper sheathing ‘good’, while other apparently similar the stamp ‘C’ above ‘DEC 1804’ (Fig. 1e). The ship was copper was ‘bad’ (Hay, 1863: 91–94). Modern analysis built at Brindley’s Yard at Frindsbury, exactly opposite shows that ‘good’ copper contained a small quantity of the Royal Yard on the other side of the Medway impurities giving a steady rate of erosion that provided River. Possibly Brindley subcontracted the task to the desired anti-fouling effect (Bingeman et al., 2000: the Royal Dockyard since the sheathing displays the 224). There were two distinct types of ‘bad’ copper. Chatham mark. Pomone was launched on 17 January Pure copper was bad since it eroded in less than two 1805 (Tomalin et al., 2000). years and was found to be unsuited for sheathing. The 36-gun Sirius was destroyed by fire at Mauritius Copper with too many inclusions, usually iron, does to avoid capture by the French on 25 August 1810. not deteriorate providing no anti-fouling effect at all Copper sheathing recovered from the wreck had ‘C’ (Bonnefoux and Paris, 1856: 253). Hay (1863: 87, 93) for Chatham above ‘SEP 1808’ (Fig. 1f). It appears used the dates on copper sheathing to reference its that Chatham Dockyard used copper supplied by condition, for instance writing ‘with copper bearing a Portsmouth Rolling Mill marked ‘P° 28’ (Fig. 1g). date subsequent to 1833’ or ‘of the quality of the copper On 15 February 1811, the 36-gun Amethyst was commenced 1832–3’. This combination of evidence anchored in Plymouth Sound waiting to be provisioned clearly shows the importance of knowing when a ship before sailing to join the fleet off Brest. Captain Jacob was coppered (Bingeman et al., 2000: 223). Walton had decided to use only the bower anchor © 2018 The Authors. International Journal of Nautical Archaeology © 2018 The Nautical Archaeology Society. Published by John Wiley & Sons Ltd. 9600 Garsington Road, Oxford OX4 2DQ, UK and 350 Main Street, Malden, MA 02148, USA. NOTE Figure 1. Sheathing marks found on Royal Navy ships HMS Agamemnon (1809), HMS Pomone (1811), HMS Sirius (1810), HMS Forte (1856–1906) and HMS Victory (1768–present), see Table 1. for what was expected to be a short period when a first deployment was in 1860 as the flagship of Rear- sudden storm drove the ship on to Cony Cliff Rocks; Admiral Sir Henry Keppel, on the Cape of Good Hope the ship was badly damaged and became a total loss. and West Coast of Africa station. In 1880, renamed All but eight of the crew survived; the Captain and his HMS Pembroke, the ship became the Chatham Naval Master, Robert Owen, were court-martialled and held Base ‘Receiving Ship’, before finally becoming a coal responsible for the ship’s loss. A rectangular 32oz, 158 hulk in 1894. Forte caught fire by accident and sank on × 132 × 0.8mm copper plate (Fig. 1h) recovered from 23 November 1905 off Sheerness (Colledge and Warlow, within Amethyst’s hull was found to have a Plymouth 2006: 131). Copper sheet from this wreck was recovered Dockyard sheathing mark (pers. comm. Mallory R. by Medway Diving Contractors Limited in 1980 during Haas, 9 February 2018). dredging and removal of obstructions for the channel Following Queen Victoria and Prince Albert’s visit leading to the Isle of Grain container terminal. The to Plymouth Dockyard in September 1843, and a sheet was on display at the Historical Diving Society petition by the townspeople, authority was given for stand during the 2001 Festival of the Sea in Portsmouth it to be renamed Devonport Dockyard. This clearly Dockyard. The date stamp shows that some of the defines the difference between the Royal Dockyard and original coppering had survived throughout the ship’s Plymouth commercial docks. It would be interesting life. to discover whether Devonport Dockyard continued HMS Victory (1768–present), the 100-gun First to use ‘PL’ or subsequently introduced a variation Rate built at Chatham Dockyard, spent her final of ‘D’. years as a training ship in Portsmouth harbour. The HMS Forte, a 3456-ton, screw-powered, 51-gun Dockyard Progress Books (ADM 180 Series) record frigate built at Deptford and launched 29 May 1858, that emergency repairs were carried out in 1887– had been coppered and marked ‘S’ above ‘MAR 1859’, 1888, when the ship was re-coppered, apart from which indicates that the ship went downstream to the keel. Now permanently docked since 1922, the Sheerness Dockyard for this task (Fig. 1i). HMS Forte’s copper sheathing was removed in the early 1960s © 2018 The Authors. International Journal of Nautical Archaeology © 2018 The Nautical Archaeology Society. 461 NAUTICAL ARCHAEOLOGY, 47.2 Table 1. Figure Mark Dockyard or No Ship description Dimension Manufacturer Comment Reference/Credit 1a HMS C above JAN Ø19mm Chatham — Uruguay Artefact sheet 923; Agamemnon 1807 courtesy of Oxford (1809) University MARE 1b, 1c HMS MR 28 Ø19mm Mines Royal 28oz plate Uruguay Artefact sheet 923; Agamemnon Company courtesy of Oxford (1809) University MARE 1d HMS Pomone C above DEC Ø19mm Chatham — Peter Hales (1811) 1804 1e HMS Pomone MR 32 Ø19mm Mines Royal 32oz plate Peter Hales (1811) Company 1f HMS Sirius C above SEP Ø19mm Chatham — Yann von Arnim (1810) 1808 1g HMS Sirius P°28 Width Portsmouth 28oz sheet Yann von Arnim (1810) 15.5mm Dockyard’s Rolling Mill 1h HMS Amethyst broad arrow, See scale Plymouth 32oz shard 3H Consulting Limited (1811) PL and on 1h JUL 1810 1i HMS Forte S above MAR Ø19mm Sheerness — John P. Bethell (1858–1906) 1859 1j HMS Victory Po MAY 1823 Ø23.5mm Portsmouth 28oz plate John Bingeman 1768–present 1k HMS Victory OCT 1888 Ø30mm Portsmouth 28oz plate John Bingeman 1768–present 1l HMS Victory P. D O C T 5mm Portsmouth 28oz plate John Bingeman 1768–present 1888 figures & letters since it trapped rainwater, causing the hull timbers to company opened a new copper refinery and rolling mill rot. The examination of the removed copper revealed at Selly Oak in Birmingham, where Gannet’s sheathing 21 different manufacturers’ and Admiralty inspectors’ would have been manufactured. The company had marks (Bingeman et al., 2000). The majority of the been very proud of winning an Admiralty contract sheathing was dated ‘OCT 1888’ (Fig. 1j) and a few and, uniquely, their broad arrow marks were embossed marked ‘P.D OCT 1888’ (Fig. 1k), the date of Victory’s to reflect this contract (Fig.