£TOS 



THE PHILIPPINE 



JOURNAL OF SCIENCE 



ALVIN J. COX, M. A., Ph. D. 



GENERAL EDITOR 



Section A 



CHEMICAL AND GEOLOGICAL SCIENCES 

 AND THE INDUSTRIES 



EDITED WITH THE COOPERATION OF 



H. C. BRILL, Ph. D. ; J. R. WRIGHT, Ph. D. ; G. W. HEISE, M. S. 

 J. C. WITT, Ph. D. ; T. DAR JUAN, A. B. ; A. H. WELLS, A. B. 



r. c. McGregor, a. b. ; h. e. kupfer, a. b. 



Volume XII 



1917 



With 11 Plates and 12 Text Figures 



MANILA 



BUREAU OF PRINTING 



1917 



