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  THEOBALD 
  : 
  GEOLOGY 
  OE 
  PEGU. 
  

  

  cal 
  truism 
  we 
  have 
  the 
  primary 
  means 
  whereby 
  the 
  main 
  physical 
  

   features 
  of 
  the 
  province 
  have 
  been 
  determined, 
  and 
  on 
  which 
  the 
  minor 
  

   and 
  ultimate 
  details 
  of 
  surface 
  configuration 
  have 
  been 
  subsequently 
  

   impressed. 
  

  

  The 
  proofs 
  that 
  such 
  has 
  been 
  the 
  history 
  of 
  the 
  formation 
  of 
  

   either 
  Yomah 
  are 
  simple 
  enough, 
  and 
  consist 
  in 
  the 
  condition 
  and 
  

   arrangement 
  of 
  the 
  beds 
  composing 
  the 
  ranges 
  in 
  question. 
  Whether 
  

   we 
  examine 
  the 
  Eastern 
  or 
  Western 
  Yomah, 
  the 
  same 
  general 
  section 
  

   and 
  arrangement 
  of 
  beds 
  is 
  displayed 
  in 
  either, 
  the 
  beds 
  being 
  tilted 
  

   up 
  and 
  folded 
  (the 
  prevailing 
  dips 
  being 
  at 
  right 
  angles 
  to 
  the 
  axis 
  

   of 
  the 
  range) 
  across 
  the 
  whole 
  breadth 
  of 
  mountainous 
  country, 
  to 
  

   which 
  I 
  here 
  comprehensively 
  apply 
  the 
  term 
  Yomah, 
  and 
  which 
  

   embraces 
  a 
  number 
  of 
  parallel 
  ranges 
  of 
  various 
  heights 
  and 
  extent. 
  

  

  It 
  is 
  not 
  my 
  intention 
  to 
  enter 
  into 
  any 
  discussion 
  as 
  to 
  the 
  causes 
  

   which 
  have 
  produced 
  the 
  lateral 
  pressure 
  in 
  question 
  ; 
  sufficient 
  it 
  is 
  

   that 
  the 
  conditions 
  of 
  the 
  beds 
  demonstrate 
  its 
  existence, 
  and 
  that 
  an 
  

   adequate 
  and 
  proximate 
  cause, 
  though 
  not 
  the 
  ultimate 
  one, 
  may 
  be 
  

   supposed 
  in 
  the 
  forcible 
  compression 
  of 
  the 
  unyielding 
  beds 
  at 
  the 
  

   immediate 
  surface 
  from 
  failure 
  through 
  shrinkage 
  of 
  support 
  below; 
  

   or, 
  in 
  other 
  words, 
  such 
  mountain 
  chains 
  as 
  those 
  bounding 
  the 
  Irrawadi 
  

   valley 
  are 
  puckerings 
  of 
  the 
  earth, 
  crust 
  along 
  lines 
  of 
  least 
  resistance 
  

   produced 
  in 
  the 
  same 
  manner, 
  mechanically 
  speaking, 
  by 
  lateral 
  pressure, 
  

   as 
  the 
  ' 
  creep' 
  which 
  takes 
  place 
  by 
  degrees 
  in 
  the 
  floor 
  of 
  a 
  deserted 
  

   coal 
  gallery 
  — 
  making 
  the 
  necessary 
  allowances 
  when 
  comparing 
  great 
  

   things 
  with 
  small. 
  

  

  It 
  may 
  be 
  asked, 
  what 
  is 
  it 
  that 
  determines 
  the 
  straightness 
  and 
  

   parallelism 
  of 
  these 
  presumed 
  lines 
  of 
  weakness, 
  granting 
  that 
  such 
  

   exist. 
  It 
  must 
  be 
  admitted 
  that 
  no 
  such 
  effect 
  is 
  ever 
  produced, 
  as 
  the 
  

   formation 
  of 
  a 
  great 
  mountain 
  chain, 
  in 
  an 
  accidental 
  manner, 
  or 
  other 
  

   than 
  through 
  the 
  operation 
  of 
  fixed 
  laws, 
  and 
  the 
  question, 
  therefore, 
  

   above 
  raised 
  is 
  a 
  pertinent 
  one. 
  In 
  the 
  present 
  instance, 
  however, 
  I 
  shall 
  

  

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