146 "^^^ Philippive Journal of Science i9i5 



tiinity for sedimentation and purification. The elevation of the 

 distribution tank is such that the water pressure in the Cebu city 

 mains is about 7 atmospheres. 



The water is neither filtered nor chemically treated at present, 

 and it does not appear likely that it will need treatment, at least 

 for some time to come. As it now leaves the taps in the city, it 

 is clear and colorless and very low in bacterial life. It is high 

 in iron, which may lead to the growth of Crenothrix later on, but 

 so far no trouble from that source has been experienced. 



The deep wells in the city of Cebu, about fifteen in number, 

 are from 25 to 36 meters deep, at which depth abundant supplies 

 of good water are encountered. In no case under observation did 

 the wells of this type show signs of sewage contamination. The 

 strata encountered in well-drilling are alluvium overlying coral, 

 none of the successful wells, so far as known, having penetrated 

 the latter. There is one artesian well on Cauit Island, near 

 Cebu. which is 90 meters deep and flows only at high tide. Its 

 salt content has almost doubled since 1906, when the well was 

 installed. 



After the installation of the municipal water system, the health 

 authorities started a vigorous campaign against surface wells, 

 with the result that the majority have already been closed and the 

 others will shortly be filled up and abandoned. Considerable 

 local opposition to the action of the authorities was developed, as 

 people naturally object to the destruction of wells, which rep- 

 resent considerable investment, and whose purity they have 

 never learned to question. Among some classes of people there 

 was even a marked antipathy to the use of the city water. How- 

 ever, that the campaign was necessarj' was clearly demonstrated 

 by the district health officer, who traced the relationship between 

 the spread of cholera and the use of well water, showing, among 

 other things, that excessive rainfall, and consequent pollution 

 of the surface wells, produced an increase in the number of 

 cholera cases in times of epidemic. As public hydrants? have 

 been placed in those parts of the city where the people are too 

 poor to pay for the water installations, and as no wells were 

 ordered closed until the city water supply was made available, 

 no real hardship has been imposed on any one. The marked 

 improvement in local health conditions has more than justified 

 the efforts of the health officials. 



Although there could be little question of the status of wells 

 in general, it had been hard to get definite and conclusive evidence 

 against suspicious sources, and people had resented having wells 



