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  F. 
  A. 
  Perret 
  — 
  Some 
  Kilauean 
  Formations. 
  

  

  estimate 
  as 
  one 
  kilogram 
  per 
  square 
  centimeter 
  — 
  the 
  impres- 
  

   sion 
  is 
  as 
  reproduced 
  in 
  tig. 
  7, 
  than 
  which 
  nothing 
  more 
  

   exquisitely 
  precise 
  can 
  be 
  imagined. 
  It 
  is 
  a 
  true 
  " 
  pressure 
  

   casting," 
  so 
  faithfully 
  recording 
  the 
  finest 
  detail 
  that, 
  from 
  it, 
  

   a 
  naturalist 
  may 
  readily 
  classify 
  the 
  original 
  tree, 
  of 
  which 
  the 
  

   lava 
  has 
  thus 
  formed 
  so 
  perfect 
  a 
  matrix. 
  

  

  The 
  reader 
  will 
  marvel 
  that 
  the 
  tree 
  was 
  not 
  marred 
  by 
  its 
  

   baptism 
  of 
  lire 
  before 
  such 
  an 
  impression 
  could 
  be 
  obtained, 
  

  

  Fig. 
  7. 
  

  

  Fig. 
  7. 
  Specimen 
  from 
  a 
  tree 
  mould. 
  

  

  but, 
  if 
  we 
  except 
  the 
  resinous 
  varieties, 
  a 
  growing 
  tree-trunk, 
  

   massive 
  and 
  full 
  of 
  moisture, 
  will 
  resist 
  carbonization 
  for 
  a 
  

   time 
  sufficient 
  to 
  permit 
  of 
  the 
  formation 
  of 
  a 
  solidified 
  layer 
  

   or 
  shell 
  in 
  contact 
  with 
  its 
  surface 
  and 
  which— 
  to 
  make 
  use 
  

   of 
  an 
  expression 
  almost 
  hackneyed 
  — 
  is 
  " 
  a 
  poor 
  conductor 
  of 
  

   heat." 
  Something 
  more 
  than 
  this, 
  however, 
  is 
  required 
  to 
  

   account 
  for 
  the 
  greater 
  marvel 
  that 
  this 
  mere 
  shell 
  is 
  not 
  then 
  

   re-melted 
  and 
  destroyed 
  by 
  the 
  flood 
  of 
  liquid 
  lava 
  at 
  full 
  tem- 
  

   perature 
  which 
  continues 
  to 
  flow 
  against 
  it 
  and 
  the 
  fact 
  that 
  it 
  

   is 
  not 
  so 
  re-fused 
  can 
  be 
  explained, 
  the 
  writer 
  believes, 
  in 
  but 
  

   one 
  way. 
  Careful 
  examination 
  of 
  the 
  mould 
  shows 
  that 
  not 
  

   even 
  the 
  contact 
  surface 
  is 
  vitreous 
  and 
  it 
  is, 
  therefore, 
  obvious 
  

   that 
  the 
  consolidation 
  has 
  taken 
  place 
  rather 
  slowly, 
  i. 
  e., 
  it 
  

  

  