392 The Philippine Journal of Science 1915 



effected by a given quantity of fuel when it is fired under a prop- 

 erly constructed boiler to produce steam for heating purposes 

 than in any other way. 



The history of the development of brine in the United States 

 is that the brine is stronger and more plentiful with depth. At 

 East Saginaw, Michigan, brine of 1° was struck at 90 feet 

 (27 meters) and increased until at 636 feet (193 meters) 90- 

 brine was reached." It may be possible that the rock from which 

 the brine springs emanate lies deep, and a mass of rock and 

 earthy matter will have to be penetrated before the source can be 

 reached. Again the brine of the Mountain Province springs 

 is probably diluted by surface seepage and a stronger brine may 

 perhaps be obtained by developing the springs and bringing the 

 brine to the surface undiluted. On the other hand, the salt may 

 have its origin in sands, silts, clays, or shales saturated with salt 

 from sea water during deposition and in which the impregnated 

 salt has been preserved by the overlying strata. 



Formerly the Philippines produced practically enough salt 

 for domestic consumption. This is no longer true. The imports 

 of salt into the Philippines have exhibited an almost constant 

 increase since American occupation. The exports of domestic 

 salt have had no influence on the trade, amounting to nothing ex- 

 cept in 1907, when there were 4,280 dollars worth exported, of 

 which 3,196 dollars came from the port of Zamboanga and 330 

 dollars from Manila, presumably the product of Malabon. Salt 

 pays an import of 20 cents per 100 kilograms when crude and 50 

 cents per 100 kilograms when ground, powdered, or otherwise 

 manufactured, and the fact that in the only year in which the local 

 supply has equaled the demand Zamboanga was able to supply 

 its local needs and to furnish a surplus for exportation seems to 

 argue that the rates imposed are sufficient for the protection of 

 the local industry. In recent years there have been no exporta- 

 tions. It is interesting to note the sources and value of our 

 imported salt. 



The principal source of our importations is China, which sends 

 only coarse salt brought in shipments of from 1- to 300-bag lots. 

 This indicates that the local production of salt does not keep 

 pace with the growth of the packing industry. Prior to 1907 

 there was not so great a demand for salt for packing purposes. 

 By actual count in 1907 there were but five Chinese engaged in 

 the packing of sardines in Tondo, but before the great Tondo 



"18th Annual Rept. U. S. Geol. Surv. (1897), 5, 1304. 



