308 Chapter 11
With the active conservation of waterlogged archaeological wood, the
major problem is not that we do not have adequate treatment methods avail-
able, it is in recognising the serious limitations of these methods. However,
those methods involving PEG offer the greatest flexibility and variability.
Dehydration techniques and methods involving in situ polymerisation are
not considered suitable for anything other than small wooden artefacts. Freeze
drying offers the conservator a safe method of drying small PEG-treated
objects while air drying is more suited to the drying of larger structures, such
as intact ships if the condition allows it.
Several problems remain to be solved before effective and new conserva-
tion methods can be developed. New treatments are being developed aimed
at controlling acid-forming oxidation processes by removing the reactive iron
sulfides and stabilising the organosulfur compounds. In this regard, the removal
of sulfides and iron compounds from the timbers of the Swedish warship Vasa
poses an important and immediate challenge to conservators charged with the
responsibility of maintaining this significant monument in a stable condition
for posterity.
References and Further Reading
M. Jones (ed), For Future Generations: Conservation of a Tudor Maritime
Collection, Cromwell Press, Trowbridge, England, 2003.
C. Pearson (ed), Conservation of Marine Archaeological Objects, Butterworths,
London, 1987.
R.M. Rowell and R.J. Barbour (eds), Archaeological Wood, Properties,
Chemistry and Preservation, American Chemical Society, Washington,
1990.
M. Sandstrom, Y. Fors and I. Persson, The Vasa’s New Battle: Sulfur, Acid and
Iron, The Swedish National Maritime Museums, Stockholm, Sweden, 2003.