3i 



The accepted dimensions are, length 20 inches, width 

 at the wide end 7 inches, at the narrow end 5 inches. 

 The concave side is purposely left rough and uneven with 

 the sand of the mould still adhering, while the upper or 

 convex surface is smoothed by hand in the usual way. 

 They are very hard, well baked tiles and their weight and 

 strength permit of considerable rough usage with com- 

 parative impunity ; annual loss from breakage is never- 

 theless heavy and has to be reckoned as one of the 

 annually recurring expenses to be faced. Under ordinary 

 circumstances the annual loss of tiles through breakage 

 and other causes cannot be reckoned at less than from 10 

 to 15 per cent. The cost varies according to the demand 

 between 45 to 50 francs (Rs. 27 to 30) per 1,000. 



To prepare the tiles in the manner most suitable 

 to ensure a satisfactory settlement upon their surfaces of 

 the oyster larvae when in the free-swimming stage, they 

 have to receive if new an initial wash of pure lime and 

 then upon this a coating of mortar ; if the tiles have 

 been previously used no lime wash is again necessary, 

 it suffices to coat with mortar alone. This process of 

 liming (chaulage) is carried out usually by women. A 

 hogshead or large barrel is used as a mixing tub. The 

 mixture used in giving the preparatory coating to new 

 tiles is simply whitewash made rather thin, pure lime 

 mixed with water to a thin creamy condition and only 

 sufficiently thick to leave quite a thin even wash on 

 both surfaces of the tiles after they are dipped into the 

 mixture. The second coating, unlike the first, must be 

 repeated annually. The mixture employed remains the 

 same as that introduced by Michelet in 1865, modified 

 in the relative proportion of the components, lime and 

 sand, according" to the individual opinion of the user. 

 The standard composition as given in works dealing 

 with oyster culture in France is always given as 1 

 of lime to 2 of sand. Practice is variable and while 

 some use the standard proportions, others increase the 

 ratio of the lime and a few that of the sand. Mr. Louis 

 Michelet, who, as the son of the inventor, has special claim 



