380 



The Philippine Journal of Science 



1916 



270 



710 

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90 



60 

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JAN. FEd. MAR. APR. MAY. JUNE. JULY. AU6. S£PT. OCT. NOV. 



Fig. 4. Normal evaporation 188E-1907, Manila. 



In view of the diminution in the rainfall and the high evapora- 

 tion one would anticipate salt works using solar heat in the 

 western half of the Archipelago to operate from December or 

 January to April or May, which accords with the actual case. 



DIFFERENT METHODS USED FOR THE MANUFACTURE OF SALT 



A method commonly known in the Provinces of Batangas, Bula- 

 can, Cavite, and Rizal by the name of iras Tagalog (native 

 method) has been used in the Philippines as long as any of those 

 now employed in the industry can remember and is probably the 

 original method used in these Islands. 



The process is as follows: Large areas of sandy land along 

 the coast, approximately at the level of high tide, are cleared of 

 vegetation and cleaned. The surface of the prepared land 

 (abuhan) is loosened, and water from canals (angkaw) , through 

 which it is led in from the sea or from the estero, is sprinkled 

 over the area where it rapidly evaporates. This process is 

 repeated about four times a day for three consecutive days, until 



