THE .RADIOACTIVITY OF PHILIPPINE WATERS* 



By J. R. Wright j and George W. Heise 



{From the Bureau of Science, Manila) 



one plate and two text figures 



In recent years there have been so many investigations of the 

 radioactivity of waters that comparative data are now available 

 from many parts of the world. It is the purpose of this paper 

 to present the results of similar work on the radioactivity of 

 typical Philippine waters. 2 



Up to the present time our work on radioactivity has been 

 limited to the determination of radium emanation and actual 

 radium content of typical springs and deep, drilled wells. As 

 yet, no attempt has been made to study the radioactivity of the 

 deposits or residues from springs, or of typical rocks, or of the 

 gases evolved from springs or wells. All of the work was done 

 on Luzon, most of it in Mountain and Laguna Provinces. The 

 majority of the places visited are shown on the accompanying 

 maps (figs. 1 and 2). 



The geography and the geology of the country in and around 

 Baguio have been described by Eveland, 3 and of the remainder 

 of Mountain Province by Smith.* 



Owing to the difficulties of travel, equipment for provincial 

 expeditions had to be reduced to a minimum; in consequence 

 comparatively few data on the chemical composition of the 

 waters were secured. 



EXPERIMENTAL PART 



The testing apparatus was one of the Spindler and Hoyer 

 aluminum leaf electroscopes used in previous radioactive meas- 



* Received for publication January 29, 1917. 



1 Professor of physics, University of the Philippines. 



2 The only previous attempt to determine the radioactivity of Philippine 

 waters was made by R. F. Bacon [This Journal, Sec. A (1910), 4, 267-280], 

 but his results were only qualitative, being obtained under conditions which 

 made even approximately accurate results impossible. 



' Eveland, A. J., Notes of the geology and geography of the Baguio 

 mineral district, ibid., Sec. A (1907), 2, 207-233. 



* Smith, Warren D., Notes on a geologic reconnaissance of Mountain 

 Province, Luzon, P. I., ibid., Sec. A (1915), 10, 177-209. 



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