356 



SCIENCE 



[N. 8. Vol. XXXVIII. No. 976 



The lowering of the lava column was natu- 

 rally accompanied by landslides due to the 

 non-support of lower portions of the crater 

 walls. Some of the avalanches were of con- 

 siderable magnitude and duration ; they gradu- 

 ally grew less in sound frequency and volume 

 until, during the latter part of the month 

 (June), they nearly ceased. Fumes and vapor- 

 ous emanations have largely obscured the in- 

 ner pit during the past months, and until 

 lately the best views gained at brief intervals 

 have shown the bottom to be largely free from 

 molten lava. Some dozen steaming outlets 

 surrounded with sulphurous deposits have at 

 times revealed themselves in the bottom of 

 the sunken well, in whose very lowest point a 

 funnel-shaped depression descending into un- 

 known depths has been momentarily disclosed. 

 On the ninth of May an unusual detonation 

 was heard toward the central portion of the pit 

 and this has been succeeded by steam explo- 

 sions resembling blasts from a locomotive's 

 funnel. In accordance with the working 

 hypothesis at the Hawaiian Volcano Observa- 

 tory, the molten magma is due to rise' on the 

 approach of the summer solstice. 



WORK AT THE VOLCANO OBSERVATORY 



Since January, 1912, regular routine work 

 has been going on in the Observatory of the 

 Massachusetts Institute of Technology, on 

 the very edge of the precipitous-sided' caldera 

 of Kilauea. In the Whitney Laboratory of 

 Seismology built in the observatory cellar 

 above steam cracks and heated from their ema- 

 nations, four large seismographs are installed, 

 including two heavy 100-kilogram Bosch- 

 Omori trinometers, and one ordinary Omori 

 seismograph for the registration of strong 

 local earthquakes; and also one heavy Omori 

 trinometer. 



On May 19, Greenwich time, the heaviest 

 shock of immediate origin yet recorded by the 

 instruments was observed. It was felt by us 

 at the Volcano House very distinctly, and even 

 more at Hilo, thirty miles distant. 



Ordinary microseismic motion has been con- 

 stantly recorded by the instruments on the rim 



of the volcano's crater, and there are more 

 rapid movements which have, in view of their 

 obvious origin, been designated as " volcanic 

 vibrations."^ 



On the very edge of the active Halemaumau, 

 in the rough building of the Technology Vol- 

 cano Station, a two-component Omori horizon- 

 tal pendulum trinometer is installed on the 

 concrete pier placed by the U. S. Geological 

 Survey as a bench mark during the survey 

 last year for the special map of the " proposed 

 Kilauea Volcano National Park." 



The instruments at the observatory will 

 probably be connected with telephone at the 

 brink of the lava lake, so that one standing on 

 its very edge may correlate his observations 

 with those being recorded two and one half 

 miles away on the high surrounding edge of 

 the Kilauea Sink; it will thus be possible to 

 note the seismic effects of changes in molten 

 magma, explosions, landslides, etc., which oc- 

 cur within a volcano's crater. Had such in- 

 struments been installed near the craters of 

 Pele and La Soufriere during the memorable 

 1902 eruptions they would not only have been 

 of service to science, but in informing the dis- 

 tracted remnant of the populations in regard 

 to the nature of the subsequent seismic dis- 

 turbances. 



Among the work being carried on under 

 Director Jaggar are: photographic record of 

 phases of volcanic activity, measurements of 

 the surface of the magma column, experi- 

 mental work with microphones, cinemato- 

 graphic registration of the activity of the 

 molten lava, spectroscopic study of volcanic 

 flames, optical pyrometry applied to the molten 

 magma in the field, studies in the temperature 

 of fumaroles and solfataras, as well as other 

 investigations relating to the geology, min- 

 eralogy, petrography and natural history of 

 Kilauea. 



STUDIES FROM KITE PHOTOGRAPHY 



In connection with the somewhat novel 

 work now being conducted at Kilauea under 



' H. O. Wood, Bull. Seismo. Soc. of Am., Vol. 

 III., No. 1. 



