﻿212 
  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  194 
  3 
  

  

  flank 
  eruption 
  on 
  the 
  northeast 
  rift, 
  began 
  2 
  days 
  later. 
  The 
  flank 
  

   eruption 
  may 
  be 
  arbitrarily 
  divided 
  into 
  three 
  phases, 
  which 
  are 
  

   characteristic 
  of 
  most 
  flank 
  eruptions 
  of 
  Mauna 
  Loa. 
  They 
  may 
  be 
  

   summarized 
  as 
  follows 
  : 
  

  

  1. 
  A 
  period 
  of 
  a 
  few 
  hours 
  during 
  which 
  very 
  hot 
  fluid 
  lava 
  is 
  

   squirted 
  from 
  a 
  narrow 
  fissure, 
  forming 
  a 
  nearly 
  continuous 
  wall 
  of 
  

   lava 
  jets 
  thousands 
  of 
  feet 
  in 
  length. 
  Lava 
  extrusion 
  forms 
  extensive 
  

   thin 
  flows. 
  Low 
  ramparts 
  of 
  agglutinate 
  are 
  built 
  by 
  spatter 
  along 
  

   the 
  fissure, 
  but 
  no 
  large 
  cones 
  are 
  formed. 
  

  

  2. 
  Restriction 
  of 
  the 
  lava 
  fountains 
  to 
  a 
  relatively 
  short 
  medial 
  

   portion 
  of 
  the 
  fissure, 
  and 
  the 
  building 
  of 
  cinder 
  and 
  spatter 
  cones. 
  

   One 
  or 
  more 
  major 
  flows 
  issue 
  continuously 
  from 
  the 
  cones, 
  and 
  numer- 
  

   ous 
  minor 
  flows 
  may 
  occur. 
  

  

  3. 
  Decline 
  of 
  the 
  fountains, 
  with 
  cooling 
  of 
  the 
  liquid 
  lava 
  in 
  the 
  

   vent, 
  and 
  decrease 
  in 
  the 
  amount 
  of 
  liberated 
  gas. 
  The 
  flow 
  of 
  lava 
  

   may 
  die 
  out 
  with 
  the 
  fountains, 
  or 
  may 
  continue 
  for 
  weeks 
  or 
  even 
  

   months 
  after 
  the 
  cessation 
  of 
  fountain 
  activity. 
  

  

  