Jaggar — Activity of Mauna Loa. 



625 



and exposure show striking dwindling in the luminosity of the 

 fume column. On November 26 the brilliantly-lighted jets of 

 vapor formed a wide band corresponding to more than one 

 mile of summit rift (fig. 3), while on November 27 the band 

 had narrowed, was brightly luminous only in one southern 

 streak with a faint secondary streak north of it. (Fig. 4.) The 

 sudden outbreak and intense activity of the first few hours 

 correspond to the explosive phase of the first few hours of 



Fig. 4. 



Fig. 4. Camp and glow over Mokuaweoweo, Puu Lehua, Kona, Nov. 27, 

 1914, 10 P. m. Photographed by moonlight ; 25 min. exposure ; Wratten 

 panchromatic plate, Tessar lens ; conditions similar to fig. 3 as to clearness 

 and distance but on opposite side of mountain. South is on the right. T. A. 

 Jaggar, phot. 



eruption in other volcanoes such as Vesuvius 

 marked a sudden release of gas pressure in a 

 relatively low viscosity. The seismic prelud 

 some months the lava was pushing its way 

 by a combination of blow piping, stoping and 

 On November 26, from the observatory, a 

 profile of Mauna Loa at about 9 a. m. showed 



and undoubtedly 

 foaming liquid of 

 e implies that for 

 upward, probably 



wedging. 



clear view of the 



a cluster of fume 

 columns, merging into a fluted curtain of thin bluish-white 



