In civilised countries the services of this
great family are not required. The
inconveniences and the costly damages they effect
are the occasion of loss, and of a serious
expenditure to prevent their ravages. It has
been estimated, that at Plymouth and Devonport
alone the boring worms have in one
year damaged Government works to the
amount of eight thousand pounds. In seventeen
hundred and thirty-one and thirty-two
they committed such ravages in the piles
forming the sea-defences of Holland, that
the Dutch were seriously alarmed. In
England, when oak timber was a drug, this wood
was much used for marine constructions,
such as harbours, groynes, &c. In Queen
Elizabeth's reign the name applied to them
in petitions, setting forth the losses sustained,
was expressive. This was Artes.

The animal of the Teredo is like a long
white worm, varying from a foot to two feet
and a half in length, and about the size of a
person's finger. Mr. Brunel perceiving how
this soft creature bored on, and encased
itself in a calcareous piece of masonry or tube
as it progresses, perceived how he might
bore the great Tunnel under the Thames.
Men drove rods into the mud from a shield,
which was moved forward as they bored
their way, and a brick arch was constructed
behind, in imitation of the calcareous tube
of the worm. Thus does observant man
treasure up and apply what even the
animals in the lower scale of creation can teach.

The destructive Teredo, like the lion, has
his jackal—the Limnoria terebrans, or gribble
worm. Wood-work in most situations, as
posts in harbours, and piles of wooden bridges,
must be protected by copper sheathing or
square-headed nails made for the purpose.
The gribble finds some little space, bores in
and destroys the wood around. The Teredo
then finds an entry and destruction follows.
The wooden bridge over the estuary of the
Teign was destroyed some years ago. Other
similar works, and particularly projecting
landing piers, have been either eaten away,
or jeopardised.

In the account that has been circulated
through the medium of the press of the
sunken fleet, its condition, and the ravages of
the worm, there is matter that is not intelligible
to one who studies the habits of the
lower animals of creation.

We are told that a diver has gone down to
visit the great fleet, which he finds in the
middle of the harbour, and upon the north
side, lying there on the sand; on the south
side, on mud.

It is further stated that the depth of water
is sixty feet. Now this is a very convenient
depth, for Man and the Teredo are limited
in their operations to the same depth from
the surface. A ship sunk in water twenty
fathoms or one hundred and twenty feet
deep is safe from the family of carpenter-
mason worms, of whatever species (and for
which consult that admirable treatise, the
Manual of the Mollusca, by S. P. Woodward,
Esq., F.G.S., of the British Museum). Man
has gone down so deep, but he can do but
little under such a pressure; and that is his
limit. Perhaps few men could descend so
far. At half that depth each of Mr. Deane's
party with his crow-bar is in power as a
giant, and in the four hours during all which
time each remained below, working at a
wreck, performed prodigies!

The Russian ships that lie upon the sand
are reported to be untouched by the worm;
while those ships upon the mud are in this
short time so much affected that they will be
worthless.

Reading this statement, many understand
that the Teredines do not exist where the
bottom is sand; and where the mud is, they
are ready to transfer themselves, like rats in
a dock, at once to do execution upon sunken
timber fully-grown and with fully developed
powers.

From my experience I can readily
believe there are seasons when the ravages of
these animals are more felt than at others.
As a member of a south-western town-council,
I learnt that elm sheathing to masonry
or oak-posts were, at times, though upon
the sand, eaten up presently.

As to the mud of Sebastopol harbour being
the habitat of the fully grown worm, this
must be quite a mistake.

The balk, floating planks, and beams of
different woods, occupied and quite
honeycombed by the Teredo, show no outward
signs of being tenanted by the carpenter-
mason. The worm entered when very minute,
when an emigrant upon the look-out for a
domicile, and fully endued with the powers
of locomotion. Some bored for three feet
and encased themselves with masonry as they
proceeded. No one interferes with another,
in which admirable social excellence they
are probably guided by sound. They work
with the grain and are not afterwards migratory.
Like Charles the Second, they have
no disposition to go again upon their travels.

A mere view would not have allowed the
diver to judge of the ravages already effected.
It may be that he cut off pieces of the ships,
and so ascertained with some precision.

The venerable line-of-battle ship sunk in
Torbay, when getting under weigh, some
seventy years ago, was eaten to pieces. When
there was motion, then pieces would break
off and float up, and fish by shoals remain
around expectant of their meal. There is no
hooking ground for fishermen so good as that
round a sunken ship.

The American contractor will go to Sebastopol
and commence operations this spring.
There is no time to be lost. As the sailor in
a late Arctic expedition pulled at a dead
deer against a wolf who laboured to carry off
the carcase, so the American will contest
with the Teredo. It may take some time