126 '^he Philippine Journal of Science i9i6 



Correspondence with the district health officer of Cebu con- 

 cerning the present status of the spring elicited the following 

 information :* 



The spring in question is located at a distance of about 1 km. from 

 the town of Oslob. It is found on the seashore which is rocky (covered 

 with broken up particles of rock, not gravel), and slopes gradually toward 

 the sea in such a way that at low tide the water recedes some 200 feet 

 from the spring. Two big rocks mark the outlets of two springs separated 

 from each other by a distance of about 30 feet * * *. One of these 

 is situated further up from the sea and has its outlet in hollowed ground 

 close to a big rock. Its flow is constant only at high tide, discharging only 

 a small amount of water, and it completely dries up at low tide. Only when 

 sea water mixes with it does the water becomes fresh, but soon gives a 

 salty taste at the return of the tide. * * * About 30 feet from the 

 spring above described, and further toward the sea, is another spring 

 which has its outlet beneath a big rock. This is a much larger spring 

 than its neighbor, discharging a large volume at high and low tide. 

 * * * Being situated at a lower level than the former spring, it is 

 completely covered with sea water at high tide to a depth of about four 

 feet. It is impossible to obtain fresh water at this time, because the water 

 of the spring can not rise up to the surface * * *. On account of their 

 identical behaviour, these two springs probably represent two outlets of 

 one and the same spring. * * * The water of the spring constitutes 

 drinking water for the town of Oslob for years beyond memory, * * *. 



Samples were obtained and analyses were made to ascertain 

 whether or not this spring, or series of springs, really gave brack- 

 ish water at low tide and fresh water only at high tide as re- 

 ported, with the following results : 



Chlorine, parts 

 Sample No. per million. 



1. Small spring at low tide 15 



2. Small spring, covered by tide 110 



3. Large spring at low tide 620 



4. Large spring at low tide (duplicate of No. 3) 610 



5. Large spring, covered by tide 840 



6. Large spring, covered by tide (duplicate of No. 5) 730 



The greater salt content of the spring waters at high tide may 

 well be accounted for by the unavoidable admixture of sea water 

 in samples secured from below the surface of the sea. 



Regarding these samples, a further letter from Doctor Cruz 

 states :* 



The small spring, a sample from which was requested at low tide, 

 was closely observed. It was noted to disappear completely at low tide, 

 as was stated in previous report. It was, therefore, impossible to obtain 

 a sample from it as was requested. However, at the return of the tide 

 and just as it reaches the large spring, but not the outlet of the small one, 



' Letter of the acting district physician. Dr. Adriano Cruz. 

 * June 17, 1915. 



