594 DAY AND SHEPHERD WATER A2TD VQLCAXIC ACTIVITY 



not of atmospheric origin — -to which further allusion will be made in the 

 concluding paragraphs. 



ASES :OLLECTED IX DECE31BER, 1 : 



hich were collected in vacunm tubes on December 4, 

 1912, much less information is obtainable than from the May collection, 

 in ?r>ite of the more elaborate preparations made for the second attempt, 

 s wholly due to the. fact already mentioned, that the dome from 

 which the December gases ere collected proved on near approach to be 

 an imperfect one, which permitted the entrance of air and a partial com- 

 bustion of the gases within the dome. Six individual vacuum tubes (two 

 of one-half liter capacity and four of 250 cubic centiniT -re auto- 



matically filled and sealed off within this dome and were brought 

 Wasiungton in safety, but were found on opening to contain mixtures of 

 volcano gases and air, such as might be expected from exposure to the 

 temperature at which they were collected (about 1,000°). There is, of 

 course, no more reason for expecting the chemical reaction between the 

 s and air to have proceeded to an equilibrium than in the case of the 

 reactions between the volcani: gasee alone, whence the analyses of the 

 gases contained in these tubes may be expected to show very variable pro- 

 portions. 



In stating the analyses the free oxygen found has been subtract e 

 gether with a corresponding portion of the nitrogen appropriate to the 

 normal composition of air. Probably more of the nitrogen should have 

 been subtracted as an equivalent for the oxygen taken up in the combus- 

 tion of the sulphur products and carbon monoxide, but the amount would 

 be difficult to fix in view of the reactions between the volcano gases them- 

 selves and it has not been attempted. The analyses at best add but little 

 to the knowledge already obtained. 



Table 4 



Am iOected in Dec '12 



Percentages by weight 



Tube 2 



CO, 



N, 24.1 



H,0 _ 



^0» none 



CI trace 



^ none 



Tube 3 



Tab* 5 



33.7 



45.4 



32.1 



21.3 





29.7 



7.6 



3.9 



none 



trace 



none 



none 



