﻿258 
  Jag 
  gar 
  — 
  Lava 
  Flow 
  from 
  Mauna 
  Loa, 
  1916. 
  

  

  speculation 
  is 
  futile 
  without 
  more 
  extended 
  records 
  for 
  com- 
  

   parison. 
  

  

  It 
  is 
  evident 
  from 
  this 
  chart 
  that 
  the 
  lava 
  of 
  Kilauea 
  was 
  

   slowly 
  rising 
  from 
  April, 
  1914, 
  to 
  May, 
  1916, 
  that 
  it 
  exhibited 
  

   a 
  spurt 
  upward 
  and 
  a 
  decline 
  synchronous 
  with 
  eacli 
  of 
  the 
  

   outbreaks 
  of 
  Mauna 
  Loa 
  1^11-15, 
  November-January, 
  and 
  

   1916, 
  May-June, 
  and 
  that 
  just 
  at 
  the 
  close 
  of 
  the 
  latter 
  out- 
  

   break 
  the 
  Kilauea 
  lava 
  column 
  sank 
  suddenly 
  to 
  profound 
  

   depths. 
  It 
  also 
  appears 
  that 
  after 
  tin's 
  time 
  the 
  Kilauea 
  lava 
  

   column 
  recovered 
  with 
  extraordinary 
  rapidity, 
  so 
  that 
  within 
  

   five 
  months 
  it 
  regained 
  all 
  that 
  was 
  lost 
  by 
  the 
  subsidence 
  and 
  

   continued 
  to 
  rise 
  still 
  higher. 
  In 
  volume 
  of 
  lava 
  this 
  rising 
  of 
  

   1916 
  amounted 
  to 
  an 
  inflow 
  of 
  approximately 
  14,567,700 
  cubic 
  

   meters 
  from 
  June 
  7 
  to 
  November 
  16 
  inclusive 
  (practically 
  a 
  

   cylindrical 
  mass 
  335 
  meters 
  in 
  diameter, 
  for 
  the 
  pit 
  was 
  left 
  

   after 
  the 
  June 
  subsidence 
  with 
  walls 
  nearly 
  vertical). 
  This 
  

   condition 
  of 
  vertically 
  was 
  quite 
  different 
  from 
  the 
  funnel 
  

   shape 
  of 
  the 
  vent 
  as 
  observed 
  by 
  the 
  writer 
  in 
  1909 
  and 
  from 
  

   1912 
  to 
  1916 
  * 
  

  

  Earthquakes 
  1915-16. 
  

  

  The 
  seismic 
  prelude 
  of 
  the 
  1911 
  outburst 
  of 
  Mauna 
  Loa 
  has 
  

   been 
  described. 
  f 
  The 
  seismographs 
  of 
  the 
  Hawaiian 
  Volcano 
  

   Observatory 
  registered 
  local 
  shocks 
  per 
  month 
  in 
  1915 
  as 
  fol- 
  

   lows 
  : 
  

  

  1915 
  

  

  Jan. 
  22 
  shocks 
  July 
  23 
  shocks 
  

  

  Feb. 
  9 
  " 
  Aug. 
  29 
  " 
  

  

  Mar. 
  22 
  " 
  Sept. 
  138 
  " 
  

  

  Apr. 
  17 
  " 
  Oct. 
  23 
  " 
  

  

  May 
  32 
  " 
  Nov. 
  13 
  " 
  

  

  June 
  30 
  " 
  Dec. 
  23 
  " 
  

  

  It 
  will 
  be 
  seen 
  from 
  this 
  table 
  that 
  from 
  nine 
  to 
  seventeen 
  

   local 
  earthquakes 
  are 
  commonly 
  recorded 
  per 
  month 
  at 
  the 
  

   Whitney 
  Laboratory,^ 
  that 
  near 
  solstice 
  and 
  equinox 
  in 
  1915 
  

   the 
  number 
  tended 
  to 
  increase, 
  and 
  that 
  the 
  approach, 
  culmina- 
  

   tion 
  and 
  recession 
  of 
  the 
  autumnal 
  equinox, 
  allowing 
  for 
  a 
  

   short 
  lag, 
  coincided 
  with 
  an 
  extraordinary 
  swarm 
  of 
  local 
  

   quakings 
  which 
  led 
  us 
  to 
  watch 
  Mauna 
  Loa 
  attentively. 
  At 
  

   the 
  same 
  time 
  the 
  lava 
  of 
  Halemaumau 
  sank 
  suddenly. 
  The 
  

   phase 
  intervals 
  of 
  the 
  seismograms 
  indicated 
  origins 
  up 
  to 
  

   sixty 
  miles 
  (97 
  km.), 
  and 
  while 
  some 
  of 
  the 
  shocks 
  were 
  of 
  

  

  * 
  Report 
  Hawaiian 
  Volcano 
  Observatory, 
  Jan. 
  -Mar, 
  1912. 
  Boston. 
  Fig- 
  

   ures 
  13, 
  25, 
  27. 
  

  

  fThis 
  Journal, 
  Dec, 
  1915, 
  p. 
  623; 
  Bull. 
  Seis. 
  Soc. 
  Amer., 
  Mar., 
  1915, 
  p. 
  

   39. 
  

  

  X 
  This 
  Journal, 
  Dec, 
  1915, 
  p. 
  623. 
  

  

  