48 The Philippine Journal of Science 



Table 3. — Results of analyses and computations (station 3). 



[Period of observations, May 21 to September 11, 1921. Numbe 



r of com 





„fe.. 1U 





&E& 



Kea Ct « 8 . 



Radicles: 



5 



*&r 



11 



















0.005 | 0.16 















3.244 100.00 



«J£ 









— 









1Z 





















Primary salinity 









100.00 



Vo 



















100.0 



an important factor in the dissolution of the siliceous materials 

 of rocks. It is further observed that the waters of Angat and 

 Montalban Rivers are primarily alkaline; and the solvent action 

 of alkalies on silica, even in very dilute solutions, has long been 

 recognized. The organic matter in these waters is too small 

 to be worthy of consideration. 



CHEMICAL PROPERTIES AND GEOLOGY OP THE DRAINAGE AREAS 



There is a remarkable similarity in the property values of 

 the waters at station 5 and station 7. Station 5 is situated at 

 Ipo, and station 7 at Montalban River. Both waters are char- 

 acterized by low primary salinity and high primary alkalinity. 

 On the other hand, the water at station 1 is characterized by 

 high primary salinity and low primary alkalinity. This ap- 

 parent difference in the chemical characters of the waters at 



