g THE BUREAU OF SCIENCE 



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Plate XLIII 32 



Fig. 1. Cane crusher near Agoo, La Union Province. 

 2. A modern sugar mill. 



Plate XLIV 32 



Fig. 1. Collecting nipa sap. Showing a native collector and 

 two bamboo joints {tuquils) in position to receive the 

 sap. 

 2. Nipa palms in fruit. 



Plate XLV 34 



Fig. 1. Fish drying in the sun. 

 2. Opium den. 



Plate XLVI 36 



Fig. 1. A leaching vat built on the ground, but high enough so 

 that the mud may be removed by gravity after the 

 leaching is completed. 

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

 A kind of cultivator used in loosening the soil is also 

 shovvTi. 



Plate XLVII 36 



Fig. 1. Showing the apparatus for transferring brine from evap- 

 orating reservoirs to crystallizing vats which are on a 

 higher level. 

 2. The lower end of a bamboo trough from the Salinas salt 

 springs, showing the well from which the brine is 

 carried to the evaporating pans. 



Plate XLVIII 38 



Testing machine breaking concrete pipes. 



Plate XLIX 38 



Portland cement manufactured from Philippine raw materials, 

 showing perfect soundness of four different mixtures from one 

 district. Average strength at 28 days, neat =780 pounds per 

 square inch; 1:3, Ottawa-sand mortar =360. All results high 

 above Government specifications. 



Plate L 38 



Cone from crushed cube of concrete from Abatan River, Cortes, 

 Bohol, showing effect of using gravel covered with green algae. 



Plate LI 40 



Philippine pottery. 



Fig. 1. Finishing a "tenaja." 



2. Beating pots into final shape. 



3. Native pottery market, Ilocos Sur. 



Plate LII 40 



Fig. 1. Pile of pottery, showing method of burning. 

 2. Glazed ware (made by first-year students). 



