ILLUSTRATIONS 



Plate I. Diagram indicating deposition of salt from sea water, showing 

 the impurities precipitated before, with, and after the salt. 



Plate II 



Fig. 1. Instrument used in sprinkling water over an area from the canals. 



2. Another type of instrument used in sprinkling water over an area. 



This process is repeated until a quantity of salt has accumulated 



on the surface whereupon the loose earth, together with the salt, 



is scraped into heaps. 



Plate III 



Fig. 1. A view of heaps of the salt-impregnated earth ready to be trans- 

 ferred to the leaching vats. In the background are to be seen 

 crystallizing' ponds protected from the wind by a bamboo fence. 

 2. A leaching vat built on the ground, but high enough so that the 

 mud may be removed by gravity after the leaching is completed. 



Plate IV 



Fig. 1. A view of another leaching vat, showing the cement-lined receptacle 

 into which the brine drains; also the implements for scraping 

 the loose earth into heaps, in transferring the salt water from 

 the canals to the leaching vats; a basket filter to break the force 

 of the sea water or brine so it will not displace the loose earth; 

 also how the mud flows are stopped during the leaching process. 

 2. A leaching vat from which the leached mud has been removed 

 preparatory to refilling. 



Plate V 



Fig. 1. An apparatus used for transferring salt water from a canal to 

 a leaching vat. It is simply an earthenware receptacle (pilon) 

 into which the water is poured and from which it is carried to 

 the leaching vat by means of a bamboo trough. 

 2. A view of the leaching process. 



Plate VI 



Fig. 1. Marking off the leached mud into squares after it has hardened 

 slightly. 

 2. A more developed and more progressive type of leach. A kind 

 of cultivator used in loosening the soil is also shown. 



Plate VII 



Fig. 1. Throwing the hardened blocks from the leach back on to the field. 

 After the second crop of salt-impregnated earth has been scraped 

 into the leach, the clods are pulverized and carefully spread out 

 to be again impregnated. 

 2. Refilling a leach. 



399 



