PEG is still used for budgetary reasons, but it now has other chemicals mixed in
to reduce the potential damage.  The ship you mentioned that is a prime example
of the damage of PEG is not Viking, but it is Swedish:  it is the great ship
VASA.  Due to the interaction of PEG with other chemicals in the wood over time,
and the mobility that PEG gave to those chemicals, the VASA is now full of tons
(no typo) of sulphuric acid.

A better approach would  Have been to add bulk and stability to the cells by
means of active hydroxyl-ended polymers, same as the best practice for leather.

J

Joseph Sullivan