32 



to attention, believes that two parts of lime to one of 

 sand give a deposit of ideal friability, a coating- which 

 flakes off in the most satisfactory manner when the time 

 comes to detach it from the tile with the oysters adherent 

 to it. When more sand than 2 to i of lime is employed, 

 the coatino- is liable to become too hard and in flaking- it 

 from the tiles such violence has to be used that too great 

 a proportion of wounded oysters results. On the other 

 hand, a mixture containing a high percentage of sand 

 appeals to the economical spirit of the poorer oyster cul- 

 turists as lime costs about Rs. 17 per cubic metre against 

 sand which may be had close at hand for the labour of 

 transport. Hence we have such variations in the pro- 

 portions used as equal parts of lime and sand ; ^ lime, 

 § sand ; § lime, ^ sand ; at the extreme of the scale 

 we have men using 3 of lime to 1 of sand and others 

 1 of lime to 3 of sand ! Where lime is readily procur- 

 able at a low cost and when the industry is flourishing 

 probably f lime to ^ sand is the proportion most 

 satisfactory but when conditions are such that every 

 small economy is of importance, as would be the case in 

 India then a reversal of the ratio (J lime, § sand) is 

 most likely to prove preferable. In this proportion 

 a cubic metre of quicklime and two cubic metres of 

 sand when mixed to a proper consistence is reckoned 

 to be sufficient to coat 12,000 tiles. 



This coating of mortar was originally applied by 

 Michelet (who was a mason by trade) by hand, much as 

 a mason lays a layer of mortar preparatory to placing 

 another brick or stone. This was found too tardy a 

 method and it was seen that if the mortar were made 

 more fluid a satisfactory coating could be obtained by 

 dipping the tiles into the mixture. Figure 10, Plate II., 

 shows the process in typical operation. Here husband 

 and wife are seen busy liming a large quantity of tiles; 

 between them stands a barrel three parts full of a 

 mixture of sand and lime stirred to the consistence of 

 thin creamy mortar. In this particular instance 1 part 

 of lime to 2 parts of sand w r as the proportion employed. 



