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DRY ROT IN SHIPS
(Being a Presidential Address delivered on 20th March, 1937).
By JOHN RAMSBOTTOM, O.B.E., Sec. L.S., etc.
PERHAPS, at the outset, it would be well to explain why
I chose dry rot in ships as the subject of a presidential
address to you.
When preparing an account of Essex Fungi I found a
number of records by Sowerby of fungi growing on wood in
Deptford dockyard and was puzzled to account for a mycologist
being allowed to pursue his studies in such a place. A short
time afterwards Mr. J. F. Sowerby showed me some manuscripts
which he had found among his great-great-grandfather's papers
which he is collating. These included a report and notes on
the condition of the Queen Charlotte accompanied by plates from
"English Fungi." On inquiring about this report from Mr.
D. B. Smith, Librarian to the Admiralty, I was given certain
information which caused me to follow up the subject. As
my interest was aroused in this way it seemed appropriate to
get together some of the facts to present to you.
It is generally known that wood which is under water remains
free from fungal attack. The timber piles of the original
London Bridge (1176) which have been recovered at odd times
were always sound ; some discovered during excavations this
year which are of elm and oak "are in a very good state of
preservation." Many similar records are known, extending
up to 1,500 years.1 Oak found in saturated ground in the
restoration work at Furness Abbey has suffered more in a few
months after excavation than it did in its original situation
during hundreds of years. The old water-pipes of London were
made of elm wood.2 The fact is that unless there is access of
air fungal decay cannot occur. On the other hand, wood which
is dry is also immune from attack, a fact which is obvious in
ancient buildings and furniture.
From the earliest times it was realised that it was possible
to treat timber so that it would resist decay and there are
1 "Venice and Amsterdam being both founded on wooden piles immersed in water, would
fall if the constancy of the situation of those piles in the same element and temperature did not
prevent the timber from rotting."—Christopher Wren.
2 "The pine, the pitch-tree, and the alder are employed for making hollow pipes for the con-
veyance of water, and when buried in the earth will last for many years." Pliny (Bostock and
Riley's Translation.)
A