[55] OYSTER AND MUSSEL INDUSTRIES. 879 
battens of wood (R), which correspond to traverses of the same size placed 
across the bottom (Q). In order that the water may circulate freely in all 
parts of the structure, the vertical bands (R) should extend some 10 
centimeters below the bottom of the chest; the planks that form the par- 
titions ought also to be placed 2 or 3 centimeters apart, or be pierced 
with a great many holes (QO). 
In this chest wooden trays of about 4 centimeters in thickness are 
placed, having two handles opposite each other (Figs. 7 and 8), and 
furnished on the opposite side with a screen of brass wire with meshes 
2 centimeters in size; the bottom is held in place by means of cords, 
nails, or galvanized iron wire. A median cross-piece (Fig. 7), consisting 
of two copper rods placed at right angles to each other, fastened at the 
ends, either to the angles of the frame (Fig. 8) or to the middle of its 
arms, increases the strength and helps to support the wire gauze. 
To make the work all the more easy, the trays ought to be square, of 
only one-half the size of the interior surface of the chest, so that it will 
be possible to place two of them on the same supports, as shown in 
Fig. 9, and there should also be sufficient space between them so that 
they may be removed or put in place without difficulty. 
Finally, shells of different mollusca, of medium size, such as the ordi- 
nary mussel, the edible cockle, commonly called coque or sourdon, of our 
various species of Venus, &c., form an indispensable part of this appa- 
ratus. , 
The method of putting the various parts together is very simple (see 
Figs. 6 and 9). After having placed the chest on the strips of timber 
which extend beyond its bottom, and having placed under these a flat 
stone which prevents them from sinking too far into the earth, some 
sixty odd selected parent oysters are spread in the vicinity; then, in 
the lower openings of the ends of the chest the first two supports (SS) 
are placed, on which two trays are laid, which are previously covered 
with a bed of mussel or cockle shells, above which other spawning 
oysters are spread. This first tier being arranged, the second is pro- 
ceeded with, and then the third, in the same manner except that in 
the third no mother oysters are admitted. 
The whole is then covered with notqed planks (D), which are held 
in place by means of a cross-piece passed through iron handles and 
tightened with wooden wedges (C). These handles being fastened in 
two posts solidly attached to the ends of the chest (P), it follows that 
in holding down the planking the cross-piece also keeps the whole 
structure together; additional strength can be given to it by nailing to 
the sides two other independent posts (P’), shorter than the first, but as 
deeply imbedded in the earth. 
Five or six months after the spawning, the young oysters having at- 
tained sufficient growth, the apparatus is taken apart piece by piece by 
an inverse operation, that is, proceeding from top to bottom, and the 
contents of each frame are carefully placed in some pare, étalage, or vivier, 
in places least affected by currents and mud. 
