BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 



Vol. 12, pp. 45-56, PLS. 2-5 DECEMBER 21. 1900 



VOLCANIC PHENOMENA ON HAWAII 



BY C. H. HITCHCOCK 



(Read before the Society June 26, 1900) 

 CONTENTS 



Page 



History of the eruption 45 



Professor Wood's observations . 47 



C. W. Baldwin's observations 47 



Professor In<^alls' observations 48 



Statements by W. R. Castle 48 



Flows along a ridge 49 



Fissures 49 



Atmospheric phenomena 49 



Mokuaweoweo 49 



Two kinds of eruptions 50 



Areas of weakness 51 



The Mauna Loa dome 51 



Volcanic ashes 53 



Origin of the ashes 55 



History of the Eruption 



The volcanic phenomena observed on Hawaii and described in this 

 paper relate to the recent eruption from Mauna Loa and the presence of 

 ash beds. 



On June 20, 1899, a very distinct earthquake shock was felt at Wailiilii, 

 my temporary residence, 23 miles from Hilo, 8 from Kilauea. and 24 in 

 a right line from the place of outburst. It was at 7.40 p. m., and lasted 

 about a quarter of a minute. At about the same hour two shocks were 

 observed at Hilo, one of them quite severe. None were noticed at the 

 Volcano house by Kilauea, which is 18 miles from the place of o'utburst. 

 A few days later another shock was felt ; also on July 11, and perhaps 

 later. It is natural to believe that these earthquakes had a direct con- 

 nection with the eruption, especially as they were particularly manifested 

 along a supposed axial line of lava accumulation. 



Vlir— BuT,r,. Geol. Soc. Am., Voi-. 12, 1900 (45) 



