DISCUSSION OF RESULTS 601 



peratures for the lava chambers below, which on other grounds must be 

 considered highly improbable. 21 



VARIATIONS IN THE COMPOSITION OF THE GASES 



In full accord with the positive conclusion that these particular gases 

 can not exist together in stable equilibrium at the temperature at which 

 they are found, but are in process of active reaction, the record of the 

 analyses shows their composition to vary from one tube to another. Suc- 

 cessive tubes collected from the volcano at the same time (table 2, page 

 588) do not show the individual gases to be present in the same propor- 

 tions, but rather in proportions which change with every bubble which 

 bursts from the liquid basin. 



VARIATIONS OF LAVA TEMPERATURE RESULTING FROM THE GAS REACTIONS 



Further confirmation of the same conclusion is found in the observa- 

 tion, already noted elsewhere, that when the gases given off by the lava 

 increase in quantity (plate 27), the quantity of lava (lava level in the 

 basin) remaining the same, its temperature increases, and, conversely, 

 when less gas is discharged through the lava this temperature diminishes 

 again. During the period of our visit in 1912 this change in the tem- 

 perature at the surface of the active lava in the basin amounted in maxi- 

 mum to 115° (June 13, 1912, 1,070°; July 6, 1912, 1,185°), and is 

 therefore much greater than could be explained in so large a basin by 

 fortuitous conditions of measurement. This absence of equilibrium and 

 consequent variability of composition is also in accord with the observa- 

 tions of Perret and others at Vesuvius, that the relative proportions of 

 the gases vary greatly with the condition of the crater. 



EXPLOSIVE LAVAS (BRUN) 



From the same viewpoint the laboratory observations of Brun on "live" 

 or "explosive" lavas and, in contradistinction, "dead" lavas acquire new 



91 Whether these gas reactions may serve as a source of heat through which to point 

 the resemblance between volcanic phenomena and geyser action (Daly) must be assigned 

 rather to the realm of geologic speculation. At all events, the superficial phenomena at 

 Kilauea would seem to find a serviceable explanation without requiring any of the eject! 

 except the gases to be of deep-seated origin. Indeed, the outbreak in May, 1012, of a 

 lava stream from the talus immediately adjacent to the lava lake and sonic 40 teel above 

 its level (plate 26) would seem to necessitate differences of pressure, and therefore 

 separate lava chambers, but short distances below the surface, in much the same thvr- 

 modynamlc relations as those supposed to exist between neighboring of different 



height and character. Hot gases from a common source percolating through chambers, 

 such as appear to honeycomb the Island of Hawaii, and reacting exothonnally through- 

 out their journey as actively as a Bunsen burner, would appear to offer rafftdenl amount 

 and variety of power to accomplish all the visible activity now seen there. 



