IMPROVEMENTS IN APPARATUS EMPLOYED IN BREEDING OR CULTIVATING OYSTERS
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by John Clayton Mewburn at the Office
of the Commissioners of Patents on the 13th April 1877. A communication
from abroad by Ernest Seguin, of Arcachon, Gironde, France.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. "IMPROVEMENTS IN APPARATUS EMPLOYED IN
BREEDING OR CULTIVATING OYSTERS." A communication from abroad by Ernest
Seguin, of Arcachon, Gironde, France.
This Invention relates to apparatus employed in breeding or cultivating oysters,
and more particularly in collecting or living the spat or young oyster.
The improved apparatus consists of a reservoir or box made of any suitable
material, and of any desired size, communicating with the exterior by water and
air supply cocks, and capable of having the upper part open without an air cock
when the apparatus is situated away from the sea and fed artificially, but closed
hermetically when the apparatus is placed so that it cnierges at each tide. In this
apparatus the collecting lives and the breeding oysters are placed at spawning
time, or spawn or spat obtained elsewhere may be put therein. A piece of silk,
the meshes of which are too fine to allow the spawn to pass through is then placed
over each water inlet and outlet, so that no spawn or spat can escape when the
water is renewed.
In either case, that is to say, whether the apparatus emerge or not, the collectors
should offer the greatest possible surface for the deposit of the spat, and be fed by
water, sufficiently clarified by filtering, so as to insure and maintain the cleanness
of the collectors. Thus the water must be renewed without sensible agitation, its
introduction be regulated by means of cocks, and a slow current obtained, con-
tinuous or intermittent, according to the position of the apparatus. The water is
renewed sufficiently often to put the spat in the best conditions of vitality and
protect it from all known causes of destruction.
The apparatus may be arranged in several ways, filtered water being always
employed as has been above stated. A simple and inexpensive arrangement is as
follows:-
The apparatus consists of a box of wood, iron, or glass, say 16 inches high,
16 broad, and 24 long. It is provided at its lower part with a cock communi-
cating with a filter situated a little below. The cover of the box, which closes it
hermetically, with the aid of strong bolts or screws, is provided with two india-
LD077

page_text: rubber tubes about a yard long, each having a valve, one of which opens outwards
to allow of the escape of the air at the rise of the tide, while the other opens
inwards to allow air to enter at the fall of the tide, or when the apparatus empties.
The box is firmly secured by stakes, to which it is only pinned or screwed, to allow
of its being removed when required, and the india-rubber tubes are placed on rigid
pipes long enough to give the apparatus time to fill before the water reaches their
top or the waves pass over.
Opening the cover of the apparatus there is placed inside it a hive which may
be composed of any sort of collectors such as are now used, but it is preferred to
make it of a series of iron or wooden frames, containing wire or other gauze, and
placed one above another. All these frames are filled with a layer of shells, broken
and sifted, and a certain number of parent oysters are placed at intervals of 10 or
15 frames apart. An apparatus of the dimensions described will contain 70 frames,
with room between them for a dozen parent oysters. These 70 frames represent a
very large surface composed of millions of collectors. There is fixed at the side of
and below the box (as has already been stated) a filter of any suitable kind, through
which the water will pass before its introduction into the box; the water arriving
with the rising tide will begin to pass into the filter, will be deprived of all foreign
matters which it holds in suspension, will then enter the apparatus above, driving
out the air through one of the valves above mentioned, and will carry sustenance to
the breeding oysters placed among the frames.
Whon the apparatus has been filled there will be no internal movement until the
sea in retiring reaching the level of the filter causes the water to flow naturally
from the apparatus, passing in the contrary direction through the filter, which is
thus cleaned at every tide. The water in retiring allows the second valve above
described to open and admit air to the apparatus. The renewal of the water takes
place twice a day.
When the oyster has emitted its spawn or spat, this spat in rising in the appa-
ratus will have to traverse 20, 30, or 50 layers of collectors; again, when the water
is retiring, it will filter through tho 70 layers of broken shells, and deposit thereon
the spat which it holds in suspension, and which in no case can issue from the
apparatus as the water runs out through silk or fabric too fine for the spat to pass.
The work going on in the apparatus can be inspected daily, and the hive can be
withdrawn when sufficiently filled and replaced by a fresh hive, and the operation
can be renewed as long as the spat lasts.
A series of apparatus can be supplied through one filter. A filter is placed on a
sloping ground in the middle of a "clairc or reservoir like those now in use for
renring oysters, and one or a series of collecting apparatus is arranged below; then,
by placing the water inlet cock at the upper part of the apparatus, a continuous
current during low water is obtained from the water contained in the "claire" or
reservoir.
There can also be introduced into the apparatus a hive composed of metal frames,
resembling a shovel, placed slightly inclined one above the other, with their incli-
nations alternately in reverse directions, the surfaces being covered with broken
shells. Seventy of these frames will present a very large surface, having millions
of collectors. The parent oysters being placed at the top, or spat or spawn obtained
from aquariums or otherwise being introduced, the spat will have to travel slowly
over this extensive surface from frame to frame, and will come in contact with the
millions of collectors to which it will attach itself.
Each apparatus can, if preferred, comprise its own filtering apparatus instead of
having the latter separately.