Coppering the wooden walls
- November 13, 2010 at 12:00 am #2802
I found Tony Beales’ article in the current Mariner’s Mirror, ‘”Great Expectations” The approach of British Ships at the Battle of Trafalgar’, MM 96:4 Nov 2010 pp455-467, most interesting especially the mention of the effects of coppering on the speed of British ships in the action.
He notes: ‘New copper was effective against fouling for up to about a year, after which docking a ship to clean its bottom would not remove much of the oxide from the copper, and fouling would then reform in a much shorter period’. His reference is D.K.Brown ‘The Form and Speed of Sailing Warships’, MM 84:3 (1998) p303.
One tends to think that coppering ships was the complete answer to fouling but we are reminded that it was not. Coppering was very expensive, some four times more than wooden sheathing, but despite the cost was considered worth it. Little seems to be written about the need to recopper ships frequently, not just to repair damage to the copper but because it was presumably no longer effective.
NAM Rodger in The Command of the Ocean : a naval history of Britain, 1649-1815 (2004), p375, writes that it cost £1500 to copper a 74-gun Ship-of-the-line during the American War between 1776 and 1783, which I calculate to be the equivalent to some £1.2million today.1
Re-calculating this by using Gross Domestic Product (in this case, Nominal GDP) as a check, in 1780 £1500 was about 0.00009% of Great Britain’s NGDP. Today that would equate to £1.25million, about a tenth of the cost of refitting a Type 23 frigate.2
Even so, to copper and maintain a fleet of a thousand ships must have been a huge financial burden at the time – in the five years or so in which this was done the total cost (taking different sizes of ship into account) would have been £1.5million by 1780, £1,250 million today. Is much written about this aspect of keeping our navy in a condition to command the seas during the latter years of the wooden world?
In H.M.S. Victory: building, restoration and repair (HMSO 1966), Arthur Bugler mentions ‘the rother’ and ‘rother irons’ (page 165). The Oxford English Dictionary gives a definition for ‘rother’ only in terms of a bullock. What is the meaning of this in ship construction terms?
1. Equivalent value of 1780 £Sterling to today worked out from inflation between 1780 and 2009 based on Retail Price Index, and as proportion of GDP data at:
2. Cost of refitting Iron Duke in 2007, £10.8m, refitting St Albans 2007-08, £14.4m; questions to the Secretary of State for Defence, Hansard 24 May 2007 col.1388W.November 25, 2010 at 12:00 am #2803Tony BealesParticipant
I’m glad you enjoyed the article, Malcolm. I think I can answer your second question. I believe ‘rother’ is an old version of the word ‘rudder’.
Your analysis of costs is most interesting, but I am afraid I don’t know whether there is much written about the economics of coppering during later years. For the time of Trafalgar, the extracts from the Progress Books in P. Goodwin, The Ships of Trafalgar: The British, French and Spanish Fleets, 21 October 1805, (London, 2005) provide a lot of interesting data as they cover the full lifetime of some ships, although the records are not complete. Amongst those ships, it looks as though most were not re-coppered more frequently than once every three or four years. Their copper was of course repaired more frequently. Often they were re-coppered as part of a larger repair (whether classed as small, middling or large), but sometimes as part of making good defects, and sometimes as part of fitting out on being re-commissioned. The costs vary so enormously that it is difficult to generalise, but the following are perhaps typical:
Belleisle: Making good defects including re-coppering, August 1805, total cost £5,494, of which the cost of materials for the hull was £3,996 and labour for the hull was £1,101.
Bellerophon: Middling repair and Fitted, including re-coppering, September 1800 – June 1801, total cost £32,608, of which the cost for the hull, masts & yards was £21,699.
Bellerophon: Fitted, including re-coppering, October 1804, total cost £11,914 of which the cost of materials for the hull was £3,349 and labour for the hull was £992.
Bellerophon: Making good defects including re-coppering, November 1807, total cost £8,026 of which the cost of materials for the hull was £1,589 and labour for the hull was £1,293.
The total cost of repairs to the Bellerophon from 1800 to 1810 was in the order of £80,000. During that period she was re-coppered four times, but I am guessing that the cost of re-coppering was perhaps not much more than 10% of the total. She did of course take a battering at Trafalgar, and the cost of refitting after the battle was £18,000, but that included only repairs to the copper and not a full re-coppering.
The cost of re-coppering would not have been the only important factor determining its frequency. I am sure the availability of dry docks and the operational requirements to keep ships at sea would have played an important part.
It is perhaps also worth remembering that even after copper lost its effectiveness against fouling, it was still effective in its primary purpose against ship-worm, providing it was undamaged. I suspect sea officers may have placed more importance on its anti-fouling properties than the Admiralty. I also imagine that Rodney’s enthusiasm for copper-bottomed ships was based on his experience with newly coppered ships.December 8, 2010 at 12:00 am #2804
In reply to my query Tony Beales says that Bellerophon was recoppered four times between 1800 and 1810, confirming the frequency and high cost of maintaining the hulls of the fleet.
Arthur Bugler, Victory: building, restoration and repair, (HMSO 1966), page 167, refers to coppering Victory in 1780 using: ‘4ft x 14inch No.40 gauge (28oz. per square foot) sheets, each weighing 8lbs.’
Brian Lavery, The Ship of the Line, volume 2, (1984), page 116, refers to 32oz. plate used: ‘on parts most vulnerable to wear such as the bows’; 28oz. plate being used elsewhere. What would the equivalent thicknesses be?
With the demand for copper sheet from the Royal Navy, production at the Parys Mountain mine in Anglesey expanded rapidly. In the days when water was the only means of transport for minerals and bulk materials the logistics of moving copper ore to the smelting and rolling mills in Holywell, Flintshire must have been considerable; also the subsequent supply of sheet to the Royal dockyards, mainly on the Thames and the south coast.
I believe the French navy in the late 18th century followed the British practice of coppering. How did France meet the needs for copper sheet?
It is interesting to be reminded that iron ships were also coppered. I cannot see any reference to Warrior being sheathed in this way but the Global Security website: http://www.globalsecurity.org/military/systems/ship/copper-sheathing, accessed 8.1.10, notes that the iron screw-frigate Inconstant was coppered from new in 1868/9.
From 1889 onwards the British Admiralty copper-sheathed vessels for foreign waters. Only with the development of successful anti-fouling paint at the end of the 19th century did copper and other forms of sheathing apparently cease.December 8, 2010 at 12:00 am #2805Colin HParticipant
This may answer the query on thickness of copper sheathing. Taking figures from my copy of Fowler’s Mechanics’ and Machinists’ Pocket Book, [edited William H Fowler, published annually, Manchester, 1908 to 1970], (1961 edition), 28oz/sq ft copper is somewhere between 19 and 20 SWG (Standard Wire Gauge) and is approx. 1mm thick (1mm = 0.03937inch).
32oz is somewhere between 18 and 19 SWG and is approx 1.1mm. thick, the thickness of the blade of my paper knife certified as being genuine copper from the Victory. The mind reels in the face of such proof!
There must be an earlier set of tables to which 40 Gauge refers, but I haven’t found that yet.December 15, 2010 at 12:00 am #2806Karel LParticipant
Very interesting information on British and French copper sheathing can be found in J.R.Harris, Industrial Espionage and technology Transfer: Britain and France in the Eighteenth Century, Ashgate Publishing c.1998. There are 20 pages in chapter 12 on the subject.December 15, 2010 at 12:00 am #2807
Thank you for the answers to date. It is surprising to learn that the difference in thickness between 28oz and 32oz copper plate is only about 0.1mm. Would such a small difference have really contributed to the 32oz plate providing greater protection for say, the bows of a vessel? It is also impressive that the rolling mill at the time was able to gauge the thickness with such precision.December 23, 2010 at 12:00 am #2808AnonymousInactive
Perhaps the definitive word on naval coppering, and other forms of sheathing for wooden vessels including the use of mailletage (nails), is the detailed article by John Bingeman, John Bethel, Peter Goodwin and Arthur Mack, ‘Copper and other sheathing in the Royal Navy’, International Journal of Nautical Archaeology, (2000) vol 29 issue 2, pp218-229. The very brief abstract reads:
‘The Royal Navy’s use of copper and other sheathing on ships as a protection against ‘worm’ is presented against a general
background of the subject. Manufacturers’, Admiralty and other marks found on metal sheathing are illustrated and identified
as an aid to nautical archaeologists.’
Two extracts which indicate the information available are, from page 221:
‘In 1761, following the favourable results from
coppering Norfolk’s and Panther’s keels, the 32-gun frigate Alarm was completely sheathed in 12-ounce (3.66 kg/m2) sheet and deployed for a 2-year trial in the West Indies (PRO, 1763). On
her return in July 1763, Earl Sandwich, the First
Lord of the Admiralty, personally went to inspect
her at Woolwich and the results were sufficiently
encouraging for further trials, which were made in 1764 on Tartar, Dolphin and Tamar using thicker copper. The Dolphin was alone in having copper
fastenings and avoided the corrosion problems of
the other two (Rodgers [sic], 1993: 295).’
And from page 228:
‘The four copper sheets of naval origin are of 28
ounce ‘weight’, one of the Navy’s 1779 standard
weights. So too are the non-naval copper sheets.
All have the Navy’s standard size of 14 x 48in.’
The article is available via the Wiley Online Library on individual subscription or via a subscribing research institution.
The references cited in the above extracts are:
PRO 1763: Navy Board Out Letters to the Admiralty, National Archives (TNA) ADM 106/2195;
Rodgers [sic] 1993: Rodger, N. A. M., The Insatiable Earl: a life of John Montagu, the 4th Earl of Sandwich, 1718-1792, London 1993, page 295.January 3, 2011 at 12:00 am #2809
Thank you Justin for referring me to the IJNA article on this subject detailing the discoveries during the reclamation work on the sunken remains of the Invincible wrecked in the Solent in 1758. It is also interesting to note:
‘Lead sheathing was not wholly discontinued by the Navy until 1770 when the new 3rd-rate Marlborough had lost virtually all her lead sheathing in 3 years’.
I was unaware too of the use of: ‘copper filling nails [copper nails tapped into the wooden plank to cover the surface] as found on the (4ft) forward section of a false keel found on the Invincible (1758) wreck site.’ The authors observed that the remaining part of the false keel was copper sheeted and [the false keel was] held in place with copper staples. The stern section of the hull also showed evidence of coppering. This work was believed to have been carried out at Portsmouth in 1757. The authors note:
‘It is known that captured French ships, being outside the strict regulations controlling the construction of British ships, were often used for various experiments involving the modification of structure or armament.’
Would these regulations have referred to the Establishment of Dimensions [Navy Board 1705 amended Admiral George Churchill (1654-1710) 1706], so strictly followed by the Surveyor to the Navy, Sir Jacob Ackworth, in the first half of the 18th century?1
Brian Lavery notes that Invincible’s false keel was coppered as an experiment, and: ‘in 1758 several more ships had their keels coppered.’2
The lines of the hull and many other features of the captured Invincible had a major influence on such as Sir Thomas Slade, Surveyor to the Navy 1755-71, responsible for designing the new British 74-gun ships, such as the Valiant and the Triumph launched in 1759 were such ships. I am particularly interested in the 74-gun 3rd-rate Hercules Class Thunderer, launched 1760. Notes I have say she was wooden sheathed but it would be interesting to know if she and other Ships-of-the-Line built at that time had their false keels either covered with copper nails and / or copper sheathed before full hull coppering for Royal Navy ships was ordered c1783.
1. John Fincham, A History of Naval Architecture, Whittaker & Co, London, 1851 reprinted Scolar Press 1979;
Brian Lavery, The Ship of the Line, volume 1: The development of the battlefleet 1650-1850, Conway Maritime Press 2004
2. Robert Gardiner (ed), The Line of Battle: The Sailing Warship 1650 – 1840 reprinted 1994, p.142.February 4, 2011 at 12:00 am #2810
July Edgerton in her Turner – The Fighting Temeraire, National Gallery, London 1995, pages 40-45, notes that Beatsons of Rotherhithe bought the Temeraire for £5,530 in 1838 for breaking, which took some 10 years. They sold back: ‘two loads of copper sheathings, pintles, braces, nails etc to the Admiralty for £3000’.
I presume all the ship breakers did this, but did the Royal ship yards recover the copper themselves or would this have been done by outside smelters? From what we have discovered, the copper sheathing only had a useful life of some 2-4 years so the sheathing removed by the breakers could not just have been used again on sea-going vessels.
I have counted some twenty five private yards on the Thames, the Medway and Essex rivers that built Ships-of-the Line (the Admiralty was rigorous in selecting builders), but I do not think any had dry docks. Maintenance of the naval fleet such as coppering and repairs would appear to have only been done by the Royal Dockyards.
It is somewhat surprising that ship repairing of naval vessels was not done by private yards, as ships needed constant attention and in peacetime all major new builds were done by the Government yards. Maybe there were capital restraints which prevented private yards building dry docks.
It would be interesting if any member could comment on this please.
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