32 THE BUREAU OF SCIENCE 



This has been the best year up to date for the field survey of 

 Philippine water supplies. Almost 200 examinations of water 

 were made at the source. Rizal, Laguna, Sorsogon, and Cebu 

 Provinces were visited. Practically every place visited had 

 specific problems for which we were able to suggest solutions. 

 Several town were considering municipal supply projects. In 

 a number of cases the choice lay between two sources, and our 

 representative was able to designate the more desirable. In one 

 instance work had been begun with the intention of using water 

 of doubtful character. 



In addition to the field water work we are endeavoring to 

 classify all of the water data on hand with a view to eliminate 

 obsolete data, secure the exact location of the sources of the 

 various waters analyzed, and make available our present know- 

 ledge of Philippine waters. We have continued our campaign 

 of instruction in endeavoring to prevent samples being taken 

 from new wells before they have been pumped long enough for 

 the water to be representative. Generally the first water from 

 a well is poorer than that taken after continued pumping, prob- 

 ably due to the leaching of soluble ingredients in the water 

 stratum. Early samples are useless and may result in the con- 

 demnation of what might have been a good well. For example, 

 a certain well yielded water containing no harmful ingredients 

 but was so turbid and unpalatable that the inhabitants used 

 water from a questionable source in its stead. Finally when 

 water was desired for a municipal supply, on the recommendation 

 of this institution, the abandoned well was subjected to a pro- 

 tracted pumping test, whereupon the water became clear and 

 unobjectionable. It may be expensive to retain a well-drilling 

 outfit long after a well is completed, especially when other sec- 

 tions are clamoring for wells, but it may be that the benefit in 

 so doing outweighs the disadvantages and may prove less ex- 

 pensive in the long run. In the case cited a thorough pumping 

 test when the well was first installed would not only have saved 

 trouble and the expense of unnecessary travel and analyses, but 

 what is more important would have made available almost a year 

 sooner a badly needed source of water. 



Owing to the unsatisfactory results achieved by the steam 

 sterilization of demijohns used locally in connection with the 

 sale of artesian water, new cleaning methods were devised by 

 the Bureau of Science and successfully installed. These methods, 

 which consist of thorough cleaning, sterilization with chloride 



