JOURNAL 



OF THE 



WASHINGTON ACADEMY OF SCIENCES 



Vol. Ill . NOVEMBER 4, 1913 No. 18 



GEOPHYSICS. — Water and the viagmatic gases. Arthur L. 

 Day and E. S. Shepherd. Geophysical Laborator}'-. 



Two serious attempts have been made in recent years to estab- 

 lish a conclusion which geologists generally have been somewhat 

 slow to accept, namely, that water of magmatic origin is not 

 found among the gases exhaled by active volcanoes.^ Notwith- 

 standing the fact that this conclusion is diametrically opposed to 

 the commonly accepted explanations of volcanic activity and 

 the further fact that the evidence offered in both instances is of 

 a somewhat fortuitous kind, it has hitherto remained uncontro- 

 verted by well-established facts of observation. It may there- 

 fore have some interest to present very briefly the preliminary 

 results of a study of the volcanic gases emanating from the Kil- 

 auea crater during the summer of 1912 the ultimate purpose of 

 which is to endeavor to establish the character and effects of the 

 chemical reactions concerned in volcanic activit}^ It happens 

 that both of the attempts to show that volcanic emanations are 

 anhydrous have depended chiefly upon evidence obtained at this 

 crater. 



The character of the evidence hitherto offered may be illus- 

 trated briefly as follows. Green noted that active lava flows, and 

 even the Kilauea crater itself, often appear to be giving off gases 

 in quantity when no steam cloud can be seen above them. Brun 

 observed that the cloud when present does not evaporate in the 

 air and shows no optical phenomena in sunhght. He was able 

 to obtain no condensed moisture in glass tubes exposed within 



' William Lowthian Green, Vestiges of the molten globe, vol. 2. 1887. Albert 

 Brun, Recherches sur I'Exhalaison Volcanique. 1911. 



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