PEG Shipwrecks

PEG-TREATED SHIPWRECKS (listed from oldest ships to youngest)

Incomplete list, a starting point

by Ellen Carrlee Conservator Alaska State Museum

March 30, 2009



Ship Name: Bercy Dugout Canoe

Location: SE Paris, paleochannel near River Seine.  (Exhibited Musee Carnavalet)

Date Sank: 3900 BC (some say 4,900 BC)

Date Salvaged: 1990’s

Conservator:  Arc-Nucleart Grenoble France

Background:  Made of oak, very poor condition, PEG 4000 for 9 months.  Mount made of polyester resin.

Source:  Arc-Nucleart website


Ship Name: Ma’agan Mikhael Ship

Location: Coast of Israel 35km south of Haifa

Date Sank:  400BC

Date Salvaged: 1988-89

Conservator:  University of Haifa, Ya’acov Kahanov

Background:  Treatment completed by 1996, now on exhibit.  Hull dismantled at sea. Pinus brutia hardwood and Quercus sp. Softwood.  Two-stage treatment, PEG 400 up to 45% and then PEG 3350 up to 100%.  Shrinkage was 2.8% with dimensions of ship within a centimeter of those recorded on wreck before salvage. 

Source: Kahanov, Ya’acov “Wood Conservation of the Ma’agam Mikhael Ship”  International Journal of Nautical Archaeology.  Vol. 26.  No. 4.  1997 pp316-329. 


Ship Name: Kyrenia

Location: Cyprus

Date Sank: 300BC

Date Salvaged: 1967-74

Conservator:  Michael Katzev

Background:  Pine?  Katzev was a classical archaeologist and according to conservator George Bass, he was the first to take a Mediterranean shipwreck hull through conservation and put on display.  Some sources say it was treated with PEG, a few months for smaller pieces and a few years for larger ones, but I can’t find the % or mw used, need to get the Katzev article.  Apparently, it was reconstructed after PEG treatment.


Katzev, M.L. “Conservation of the Kyrenia Ship 1971-72”  National Geographic Society Research Report.  Vo. 12 pp. 417-426.


Ship Name: Marsala Punic Ship

Location: Marsala, Italy (Palermo Archaeological Museum)

Date Sank: circa 241 BC

Date Salvaged: 1971-75

Conservator:  Pietro Alagna

Background: Oak, pine, and maple.  Hull dismantled to fit into tanks.  Treated with PEG 4000 up to 80% for 250 days (a little more than 8 months) at 60C.  In preliminary tests, a piece of maple had done better treated with PEG 1200 first and then PEG 4000.

Source:  Alagna, Pietro.  “The Construction of the Treatment Tanks Used in the Conservation of the Wood of the Marsala Punic Ship.” Studies in Conservation Vol. 22.  1977 pp 158-160.


Ship Name: Thracian one-log boat


Date Sank: 200 BC?  Bronze Age

Date Salvaged: early 1970’s

Conservator: Anton Mihailov

Background:  Abstract from BCIN describes an accelerated (262-day) treatment for dugout Thracian canoe of Mountain ash (Fraxinus excelcior). Preliminary wetting in a 1% PEG 1500 bath with 0.2% sodium pentachlorophenolate as a biocide, gradually increasing the PEG 1500 concentration to 30% and the biocide concentration to 0.5%; as the concentration of PEG was increased to 40%, 20% PEG 4000 was included; as the concentration of PEG was increased further, the proportion of PEG 4000 was raised and glycerine added in amounts ranging from 0. 5% up to 2%. Temperature was elevated to 64°C, PEG concentration was stabilized at 85% and cooled to 50°C (122°F); cleaning by means of heat, ethanol and methylated spirits is described, as well as post-cleaning surface treatment with Cosmoloid microcrystalline wax, Paraloid B 72 and toluene.  Also treated another dugout canoe of oak in 1972 ICOM report using PEG 3000 for 475 days.

Source: Anton, Mihailov. “Conservation of a Thracian one-log boat.”  In book. ICOM Committee for Conservation 5th triennial meeting: Zagreb, 1-8 October 1978: preprints. International Council of Museums (1978)


Ship Name: Gallo-Roman Boats of Pommeroeul

Location: Pommeroeul, Belgium

Date Sank:  100-200 CE

Date Salvaged: 1978-82

Conservator:  Eddy DeWitte, Alfred Terfve, Jozef Vynckier and others

Background:  Wooden river boats made from green oak with no sapwood.  Stored for 5 years, impregnated with PEG 4000 at 65C in a tank for 2 years.  Reassembled by Michael Esnault, Patrick Chasse, Philippe Duhaut working under Alfred Terfve.

Source:  De Witte, E., A. Terfve, and J. Vynckier.  “The Consolidation of the Waterlogged Wood from the Gallo-Roman Boats of Pommeroeul.”  Studies in Conservation Vol. 20 No. 2.  1984.  pp. 77-83.


Ship Name: Prow of Roman boat from Marseilles

Location: Place Jules Verne Marseilles, France

Date Sank: 200-300 CE

Date Salvaged: ?

Conservator:  Arc-Nucleart Grenoble, France

Background: Treated with PEG 400 and 4000.  Elaborate mountmaking for exhibit

Source:  Arc-Nucleart website



Ship Name: Gallo-Roman Barge from Yverdon-les-Baines

Location: Yverdon-les-Baines, Switzerland

Date Sank: 400CE

Date Salvaged:  1984

Conservator:  Gilbert Kaenel?

Background:  Made of oak.  Removed whole, treated with PEG 4000 15-85% at 60C.  Museum look is said to be “high quality natural finish”

Source:  Kaenel, G. “PEG conservation of a Gallo-Roman barge from Yverdon-les-Bains (Canton of Vaud, Switzerland).” In Hoffmann, Per, ed. Proceedings of the ICOM Group on wet organic archaeological materials conference, 5 (Portland/Maine, 1993). Bremerhaven : ICOM, 1994.  pp143-163.


Ship Name: Shinian Ship (Chinese vessel)

Location: Shinian, SW Coast of Korea near Jeunglo Island

Date Sank:   1000-1100 (11th Century Yuan Dynasty)

Date Salvaged: 1976-1984

Conservator: Mokpo Conservation Center, est.1981

Background: Red pine.  5% PEG 400 at room temp, discarded when smelly, increased by 5% PEG 400 every 3-4 months until 20%.  Tried removal of iron around nail holes etc mechanically and with EDTA but not satisfactory.  Heated up to 40 degrees C (104F): 25% PEG 4000 increased 5% evert 2-3 months until 70-80% total.

Source:  ICOM-CC WOAM Newsletter No 19 March 1990 pp9-11.


Ship Name: Skuldelev Viking Ships

Location: Roskilde, Denmark

Date Sank: 1070

Date Salvaged: 1962

Conservator:  B. Brorson Christensen  National Museum of Denmark

Background: 5 ships intentionally sunk in a narrow channel as a barricade protecting the trading town of Roskilde.  Viking Ship Museum built in 1969.  1970 publication: they began with 10% PEG 4000by weight, raised to 60C. Addition of more in small amount daily.  Small finds were done in 7 months, but timbers had distortion at that duration and longer time was needed for them, usually 12-24 months. Pine did well but oak still had some collapse. 

Analysis indicates that PEG has not broken down to a lower MW in 40 years?  Large amounts of PEG could be extracted from degraded parts of the ships but hardly any from sound parts. Mass spectrometry showed that PEG 4000 is present only in the surface layers of the wood, PEG 1500 and PEG 600 are present at all depths of the wood that has been treated with it. Low molecular weight PEG was detected in one of the Skuldelev ships by mass spectrometry and Size Exclusion Chromatography (SEC), it is argued that this is due to degradation of PEG 4000. SEC also showed that PEG 600 is the major PEG component in the Vasa which makes this particular object sensitive to changes in air humidity since PEG 600 is hygroscopic.

Grattan and Clarke: Christensen overlooked the use of low mw PEG.  He did do some testing of enzyme to improve permeability.  Difficulty of the tyloses in vessels in the oak heartwood blocking penetration.  Also tried the use of PEG in solvents.  Other issues have arisen, as described in 2002 publication. 


Motensen, Martin Nordvig, Egsgaarde Helge,  Søren Hvilsted, Yvonne Shashoua, Jens Glastrup.  “Characterisation of the Polyethylene Glycol Impregnation of the Swedish Warship Vasa and one of the Danish Skuldelev Viking Ships”  Journal of Archaeological Science. Vol.34, No8,2007.  pp. 1211-1218


Crumlin-Pedersen, Ole and Olaf Olsen The Skuldelev Ships I  Roskilde Viking Ship Museum and the National Museum of Dernmark.  2002.  Review online of the book includes useful info:


Grattan, D.W. and R.W. Clarke.  “Conservation of Waterlogged Wood.”  In, Conservation of Marine Archaeological Objects. Ed Colin Pearson.  Butterworth. London and Boston. 1987. 164-206   


Christensen, B. Brorson.  “The conservation of waterlogged wood in the National Museum of Denmark. With a report on the methods chosen for the stabili zation of the timbers of the viking ships from Roskilde Fjord, and a report on experiments carried out in order to improve upon these methods” Studies in museum technology, National Museum of Denmark Copenhagen 1970.


Ship Name: Bremen Cog

Location: Bremer, Germany  Weser River (Deutsches Schiffahrtsmuseum)

Date Sank: 1380

Date Salvaged: 1963

Conservator:  Per Hoffmann

Background: Found during dredging for new dock in 1962.  2-step PEG treatment for 19 years.  Reassembled and a tank built around it for total submersion.  Tank cut away after treatment.  1985-1995 PEG 200.  1995, switched to PEG 3000 up to 63%.  Treatment ended in 1999.  Note, it was found in fresh water and is not suffering the acid issue of the Vasa.

Source:  Also, many articles written by Per Hoffmann


Ship Name: Mary Rose

Location: Portsmouth, England

Date Sank: 1545

Date Salvaged: 1982

Conservator: Mary Rose Trust

Background:  Oak with elm keel.  Almost the entire starboard side was salvaged.  3,000+ timbers were recovered and placed in storage.  Treatment did not begin until 1994, with spraying of PEG 200 up to 40% until 2005 and then PEG 2000 currently aiming to continue until 2011 and increase to final concentration of 50-60%.  Suffering from sulfur and acid problems like the Vasa, but luckily still in a wet treatment phase.


Unger, Achim; Schniewind, Arno P.; Unger, Wibke  Conservation of Wood Artifacts : A Handbook.  Natural Science in Archaeology Series.  Springer Verlag  New York. 2001.


Ship Name: Vasa

Location: Harbor of Stockholm, Sweden.  Brackish salt water, very polluted

Date Sank: 1628

Date Salvaged: 1961

Conservator:  Swedish National Maritime Museums

Background: Brackish water not salty enough for shipworms, pollution killed a lot of bacteria

This was the first big PEG treatment for a shipwrecked hull, sprayed for 17 years

1962-1971 sprayed with PEG 4000 and PEG 1500

1971-1979 PEG 600 for better penetration

From 1965-1971 PEG solution was continuously recirculated.  Concentration never over 45%.  Final hand sprayed coating of 45% PEG4000 then hot air to finish surface.


In 2000 acid problem discovered.  PEG corrodes iron, and the iron catalyzes oxidation of sulphur to make sulfuric acid.  The sulphur was made by bacteria in an anaerobic environment.  Bacteria take sulphur from seawater and reduce sulphate ions to hydrogen sulphide.  Early on, spraying with Borax (5 tons) to kill bacteria helped neutralize the acid, since Borax is alkaline.  Now, they are considering using chelating agents to complex the iron.  EDMA complex is orange, but works a lot better than DTPA. 

This issue apparently is happening to a lot of shipwrecks treated with PEG, except for the Bremen Cog which was found in freshwater?  MW of the PEG 30 years later seems to be similar.  Also issues with formic and acetic acids.  Formic may be related to the PEG, but acetic may be from the wood.




Ship Name: Batavia (United Dutch East India Company)

Location: Freemantle, Western Australia

Date Sank: 1629

Date Salvaged: 1972-1976

Conservator:  Ian MacLeod, James Pang

Background:  Oak with Baltic pine sheathing, pine masts.  Could be fully immersed in PEG, since it was excavated in parts.  PEG 1450 was used, according to Grattan and Clarke. Up to 90% over 2-3 years at 60degreesC.  Surface was brushed with PEG 6000.  Issue of iron corrosion products as pyrite in timbers.  Deacidified with gaseous ammonia.  In 1990, surfaces were becoming fragile.


Unger, Achim; Schniewind, Arno P.; Unger, Wibke  Conservation of Wood Artifacts : A Handbook.  Natural Science in Archaeology Series.  Springer Verlag  New York. 2001.


Grattan, D.W. and R.W. Clarke.  “Conservation of Waterlogged Wood.”  In, Conservation of Marine Archaeological Objects. Ed Colin Pearson.  Butterworth. London and Boston. 1987. 164-206   


Ship Name: LaBelle

Location: Matagorda Bay, Texas

Date Sank: 1687

Date Salvaged: 1996 (cofferdam)

Conservator: CRL at Texas A&M

Background: Began soaking in PEG in 2002?  1/3 of the ship survives.  They built a large outdoor vat covered with a greenhouse-like tent around 2001.  Ship was reassembled in the vat?



Ship Name:  Machault

Location: Restigouche River, Chaleur Bay (Restigouche National Historic Site Visitor Center, New Brunswick)  Canada.

Date Sank: 1760

Date Salvaged: 1969-1972

Conservator:  Parks Canada

Background:  Mostly made of oak.  David Grattan says, “The Machault in Canada, though ultimately successfully conserved with PEG, initially encountered problems when an untested sand drying process was tried out. This was in the early days of conservation in Canada.” After the sand drying didn’t work, they sprayed with 15% PEG 540 blend (1540 and 300).  Trials of 25% did not soak into the wood.  Schedule from 1977-1979 went: 4 months of 15%, 4 months 25%, 18 months 25% and 6 months 100% each time applied 3X per week.  Then they decided to apply thick molten PEG 540 directly to the timbers.  This was absorbed very quickly, and they continued at 6 month intervals.  They say the wood is not having trouble as of 1982, but they are concerned about fungicide sodium pentachlorophenate as high as 9000ppm.


V. Jenssen and Lorne Murdock, “Review of the Conservation of the Machault Ships timbers (1973-1981)”, Proceedings of the ICOM Committee for Conservation Working Group on Waterlogged Wood Conference, Ottawa, 1981, D.W. Grattan ed., J. C. McCawley ed. special discussions. (Ottawa: ICOM Waterlogged Wood Working Group, 1981)


Ship Name: Mallorytown Wreck

Location: Ottawa?

Date Sank: 1812?

Date Salvaged: 1967

Conservator:  Parks Canada

Background:  20% PEG 1000 then 12.5% PEG 1450  Poorly treated in the beginning?

Source:  David Grattan posting to the distlist


Ship Name: USS Cairo Gunboat

Location: Yazoo River near Vicksburg, Mississippi

Date Sank: 1862

Date Salvaged: 1960-64

Conservator:  eventually, National Parks Service (1977)

Background: Originally salvaged by an organization of local enthusiasts called “Operation Cairo.”  Decision was made to pull up the ship first, then decide on treatment and funding afterward.  Widely considered an archaeological disaster.  Yanked up in pieces, considerable theft, not treated for many years and largely destroyed. 

Source:  H. Thomas Mc Grath, Jr., “The Eventual Preservation and Stabilization of the USS Cairo”, The International Journal of Nautical Archaeology and Underwater Exploration (1981) 10, 2 pp. 79-94.



Ship Name: Dover Bronze-Age Boat

Location: English Channel, Dover, Kent, Southern England.  (Dover Museum)

Date Sank: 1300-1600BC

Date Salvaged: 1993

Conservator: Mary Rose Trust, Jacqui Watson

Background:  Removed from a freshwater silt by cutting into sections.  Treated with PEG for a year (have not found what % or mw) and then freeze-dried.  Minor distortion, but enough to cause difficulty with reconstruction.




Ship Name: Brown’s Ferry vessel

Location: Black River in eastern South Carolina

Date Sank: 1735 to 1740

Date Salvaged: 1976

Conservator: Katherine Singley

Background:  Made of live oak, pine, and cypress.  PEG 1450 was to be used, heated to 60C, increased by 1% every two weeks up to 60%.  Two years projected, slow air drying in low humidity planned.  Intended to apply 30% solution of PEG 4000 after that.  Dried under a tensioned cradle system? Treatment began around 1982?

Source Singley, Katherine R. “The recovery and conservation of the Brown’s Ferry vessel” In book. Proceedings of the ICOM Waterlogged Wood Working Group conference: Ottawa, 15-18 September 1981. ICOM Waterlogged Wood Working Group (1982), pp. 57-60


One Response to PEG Shipwrecks

  1. Claire Dean says:

    Just a small correction – the narrative in the entry for the Kyrenia (Cyprus)describes Geeorge Bass as “conservator”. George was/is an archaeologist and considered by many to be the father of underwater archaeology (especially of ships). I have had the honour of working with him in Turkey.

    Just thought this might be a useful clarification.

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