﻿286 
  Jaggar—Lava 
  Flow 
  from 
  Mauna 
  Loa, 
  1916. 
  

  

  trading 
  parts, 
  itself 
  subsided 
  through 
  withdrawal 
  of 
  support 
  

   beneath. 
  They 
  never 
  appeared 
  to 
  be 
  floating. 
  Shoals 
  were 
  

   disclosed 
  (fig. 
  9) 
  when 
  the 
  lake 
  had 
  gone 
  down 
  not 
  more 
  than 
  

   thirty 
  feet 
  (9 
  m.) 
  and 
  the 
  pool 
  became 
  converted 
  into 
  a 
  torrent 
  

   pouring 
  eastward 
  toward 
  drainage 
  conduits 
  which 
  seemed 
  to 
  

   be 
  of 
  limited 
  size 
  in 
  the 
  floor 
  of 
  the 
  sinking 
  saucer. 
  Tumbles 
  

   of 
  talus 
  from 
  the 
  benches 
  into 
  the 
  lake 
  were 
  not 
  deeply 
  en- 
  

   gulfed, 
  but 
  protruded 
  above 
  the 
  shallow 
  pool. 
  It 
  is 
  difficult, 
  

  

  Fig. 
  8. 
  

  

  Fig. 
  8. 
  East 
  inner 
  wall 
  of 
  Halemauinau, 
  10:30 
  a. 
  m., 
  June 
  5, 
  1916, 
  during 
  

   the 
  sudden 
  subsidence. 
  Benches 
  falling, 
  incandescent 
  talus, 
  lava 
  lake 
  on 
  

   left. 
  Depression 
  400 
  feet 
  (122 
  m.). 
  Photo. 
  Jaggar. 
  

  

  however, 
  to 
  imagine 
  what 
  supported 
  the 
  saucer 
  and 
  what 
  was 
  

   withdrawn 
  when 
  the 
  saucer 
  sank. 
  The 
  subject 
  of 
  the 
  cross- 
  

   section 
  of 
  Halemaumau 
  deep 
  down 
  is 
  a 
  matter 
  for 
  special 
  dis- 
  

   cussion. 
  

  

  The 
  withdrawal 
  was 
  so 
  extensive 
  that 
  the 
  old 
  walls 
  outside 
  

   of 
  the 
  recent 
  inner 
  benches 
  of 
  overflow 
  were 
  undermined 
  and 
  

   crumbled 
  inward, 
  especially 
  below. 
  The 
  upper 
  rim 
  of 
  the 
  pit 
  

   remained 
  unchanged. 
  Throughout 
  the 
  day 
  the 
  writer 
  was 
  

   able 
  to 
  work 
  with 
  transit 
  and 
  camera 
  on 
  the 
  rim 
  without 
  in- 
  

   convenience 
  except 
  for 
  occasional 
  whirlwind 
  blasts 
  when 
  it 
  

   was 
  necessary 
  to 
  lie 
  down. 
  The 
  earthquakings 
  were 
  insignif- 
  

  

  