S06 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [54] 
mud, resulting from the stagnation of the water, the claire should not. 
receive a new supply of water from the sea without giving it a chance 
to deposit the greater part of its sediment, which can be accomplished 
by keeping it for a certain length of time in a special basin. These 
basins themselves might be made of service by providing them with 
gates and sluices, and using them as breeding or fattening ponds for 
mussels or other marine animals. Fig. 18 gives a bird’s-eye view and 
Ss 
SY 
YY ‘ 
\\ YY 
\ 
NHN NN WY 
A SN 
OMY 
Fic. 18.—Claires. Vertical section, and bird’s-eye view. 
also a cross-section of two rows of claires with their feeding and puri- 
fying basins. The following explanation will sufficiently explain all the 
details given. CC, C’ represent two claires seen in section, the one dug 
into the bank, the other on the same level but nearer the open water. 
The sides or slopes of the former, B, B, consist of a layer of rough stones 
cemented together; the sides B’, B’ of the second are formed of thick 
walls, about two meters in height above the bottom of the claire, and 
about 1.40 meters in thickness at the bottom and .75 to .80 of a meter at 
the top, with an equal slope upon either side, f, f, of the bottom of each 
claire, the center being higher than the sides by about .30 of a meter. 
V, V, sluices and gates for the entrance of water from the sea. 
V’, sluice and gate between two of the claires, to allow the entrance 
of water into one, only after remaining a certain time in the other, and 
to establish the same levels in both compartments. 
S, basin for the deposit of the sediment contained in the sea-water 
which enters through the gate V’’.. It can also be used, if desired, as a 
supply reservoir, for the claires during the intervals between the spring- 
tides. In this case it should be constructed in the same manner as the 
claires themselves, so as to retain the water stored in it. Otherwise it 
will only be necessary to make the,dikes of dirt. In any case it ought 
to be proportioned in size and capacity to the claires which it supplies. 
T, T’, canal through which the water enters from the sea. 
