﻿Jaggar—Lava 
  Flow 
  from 
  Mauna 
  Loa, 
  1916. 
  257 
  

  

  that 
  volcano. 
  Id 
  each 
  case 
  the 
  local 
  earthquake 
  spasms 
  

   occurred 
  at 
  the 
  beginning 
  of 
  the 
  pronounced 
  subsidence 
  of 
  

   Kilauea 
  lava 
  after 
  a 
  temporary 
  spurt 
  of 
  rising. 
  A 
  greater 
  

   earthquake 
  spasm 
  of 
  September, 
  1915, 
  accompanied 
  a 
  more 
  

   pronounced 
  rise 
  and 
  fall 
  at 
  Kilauea. 
  

  

  The 
  period 
  September 
  to 
  November, 
  1914, 
  exhibited 
  high 
  

   seismicity, 
  which 
  ceased 
  when 
  the 
  summit 
  crater 
  flows 
  of 
  

   Mauna 
  Loa 
  poured 
  forth 
  freely 
  in 
  December.* 
  The 
  rising 
  of 
  

   the 
  Kilauea 
  column 
  spurted 
  synchronously 
  with 
  the 
  term 
  of 
  

   the 
  Mauna 
  Loa 
  outbreak. 
  Excepting 
  for 
  the 
  July-September 
  

   rise 
  of 
  1915, 
  the 
  Kilauea 
  column 
  remained 
  well 
  below 
  the 
  

   400-foot 
  (122 
  m.) 
  mark 
  in 
  the 
  pit 
  for 
  the 
  year 
  February, 
  1915, 
  

   to 
  February, 
  1916, 
  and 
  then 
  it 
  climbed 
  rapidly 
  and 
  a 
  sudden 
  

   spurt 
  in 
  May, 
  1916, 
  culminated 
  this 
  rising 
  spell, 
  apparently 
  in 
  

   coordination 
  with 
  the 
  new 
  outbreak 
  of 
  Mauna 
  Loa, 
  and 
  its 
  

   swarm 
  of 
  earthquakes. 
  Thereupon 
  the 
  lava 
  of 
  Kilauea 
  sank 
  

   suddenly 
  with 
  cataclysmal 
  effect, 
  accompanied 
  by 
  a 
  localized 
  

   earthquake 
  spasm, 
  and 
  immediately 
  recovered, 
  rising 
  with 
  

   increased 
  volume 
  and 
  rapidity 
  until 
  the 
  present 
  time 
  (Novem- 
  

   ber, 
  1916), 
  except 
  for 
  a 
  sluggish 
  month 
  in 
  September. 
  

  

  A 
  general 
  tendency 
  to 
  culmination 
  at 
  equinox 
  and 
  solstice 
  is 
  

   evident 
  throughout 
  the 
  chart, 
  and 
  this 
  habit 
  has 
  proved 
  useful 
  

   in 
  guiding 
  expectation, 
  as 
  for 
  instance 
  at 
  the 
  present 
  time, 
  

   when 
  it 
  is 
  reasonable 
  to 
  look 
  for 
  a 
  turning 
  point 
  in 
  the 
  great- 
  

   rise 
  about 
  December, 
  1916. 
  The 
  writer 
  surmises, 
  however, 
  

   that 
  a 
  gas 
  pressure 
  control, 
  with 
  release 
  and 
  recovery 
  depen- 
  

   dent 
  on 
  accumulation 
  and 
  resistance 
  in 
  an 
  adjusted 
  conduit 
  

   system, 
  is 
  effective 
  in 
  inducing 
  rhythm 
  in 
  volcanic 
  mechanism, 
  

   as 
  he 
  pointed 
  out 
  for 
  Mont 
  Pele 
  in 
  1902, 
  when, 
  however, 
  he 
  

   supposed 
  the 
  gas 
  to 
  be 
  water 
  vapor, 
  f 
  The 
  luni-solar 
  stresses, 
  

   superposed 
  on 
  the 
  more 
  dominant 
  long-term 
  trends 
  inherent 
  in 
  

   the 
  ever-rising 
  gas 
  and 
  lava, 
  probably 
  act 
  as 
  trigger 
  in 
  opening 
  

   and 
  closing 
  fissures, 
  but 
  the 
  two 
  curves 
  respectively 
  of 
  summit 
  

   culminations 
  and 
  sudden 
  depressions 
  at 
  intervals 
  of 
  about 
  eight 
  

   months 
  shown 
  on 
  this 
  plat 
  imply 
  increasing 
  maxima 
  without 
  

   respect 
  to 
  any 
  obvious 
  astronomic 
  period. 
  If 
  this 
  tendency 
  

   led 
  to 
  a 
  fourth 
  crisis 
  of 
  like 
  interval 
  we 
  might 
  expect 
  Halemau- 
  

   mau 
  to 
  overflow 
  before 
  February, 
  19174 
  and 
  thereafter 
  to 
  col- 
  

   lapse 
  still 
  more 
  profoundly 
  than 
  in 
  June 
  of 
  1916. 
  But 
  such 
  a 
  

  

  *This 
  Journal, 
  Feb., 
  1915, 
  p. 
  167 
  ; 
  Dec, 
  1915, 
  p. 
  621 
  ; 
  and 
  May, 
  1916, 
  p. 
  

   383. 
  

  

  t 
  Science, 
  Nov. 
  28, 
  1902, 
  p. 
  871. 
  See 
  also 
  Gilbert, 
  " 
  Earthquake 
  fore- 
  

   casts." 
  Science, 
  Jan. 
  22, 
  1909, 
  p. 
  121. 
  

  

  X 
  On 
  Feb. 
  1, 
  1917, 
  the 
  lava 
  was 
  still 
  rising 
  and 
  less 
  than 
  50 
  feet 
  (15m.) 
  

   below 
  the 
  rim 
  of 
  the 
  pit. 
  (Author, 
  Feb. 
  2, 
  1917.) 
  

  

  Fig. 
  1. 
  Diagram 
  showing 
  fluctuation 
  of 
  level 
  of 
  lava 
  in 
  Halemaumau, 
  in 
  

   relation 
  to 
  seismic 
  and 
  volcanic 
  activities 
  of 
  Mauna 
  Loa, 
  1914-1916. 
  

  

  