180 On the Strength, Durability and Value 
nearly an inch in diameter; but where the copper was left, 
the wood appeared to be as sound as ever. A specimen was 
not obtained large enough for testing, the piece having been 
roughly cut out before it was known to be required for the 
experiment. 
Another most destructive marine animal, though of very 
minute size, and which appears to be a species of Limnoria, 
attacks this and other woods in these seas, from the water's 
edge downwards. It is about 2, of an inch in length, and is 
supposed by some to dissolve or soften the wood by means 
of a glutinous substance which it is thought to have the 
power of producing, and to make its way through it by this 
means rather than by boring. I have observed in it the ap- 
pearance of very minute boring mandibles, with which it may 
probably gnaw its way ; but it 1s rather difficult to distinguish 
them, even with a good instrument. A viscid fluid seems to 
attach the ova to its under surface and between its legs, 
whence they sometimes protrude. A figure of this little 
ereature, which answers to the description given by natural- 
ists of that found on the coasts of England and Holland, is 
appended to this paper. 
Where it has entered, the wood appears to be literally alive, 
and honeycombed in every direction. Several of the piles 
on the Wharf, though apparently sound above high water- 
mark, are completely eaten away by it under water. 
It does not appear that any preventive means to its attack 
have ever been tried, except coppering; but the surface 
seems to be effectually preserved by charring. The piece of 
charred wood upon the table was part of the mast of a vessel 
accidentally destroyed by fire about ten years ago in this 
harbour. It has since been used as portion of a floating 
stage or raft for repairing vessels in Mr. Watson’s yard. 
The Limnorie do not appear in any of the charred parts, 
