﻿144 
  THEOBALD 
  : 
  GEOLOGY 
  OF 
  FEGTT. 
  

  

  actual 
  dividing 
  range, 
  but 
  Shuaydoung 
  marks 
  a 
  focus 
  of 
  exceptional 
  

   disturbance, 
  geological 
  and 
  physical. 
  Within 
  the 
  limits 
  of 
  Pegu, 
  

   serpentine 
  nowhere 
  occurs 
  on 
  the 
  Western 
  slopes 
  of 
  the 
  Arakan 
  range 
  ; 
  

   but 
  in 
  the 
  Sandoway 
  district 
  of 
  Arakan, 
  it 
  must 
  be 
  largely 
  developed 
  

   in 
  some 
  parts 
  of 
  the 
  valley 
  of 
  the 
  Maii 
  river, 
  to 
  judge 
  by 
  the 
  quantity 
  

   of 
  pebbles 
  of 
  this 
  rock 
  seen 
  in 
  the 
  bed 
  of 
  the 
  river 
  about 
  Lyndi. 
  

   The 
  first 
  mass 
  of 
  serpentine 
  South 
  of 
  the 
  frontier 
  is 
  that 
  which 
  consti- 
  

   tutes 
  Bidoung 
  hill, 
  five 
  miles 
  South-by-east 
  of 
  Pathi. 
  Descending 
  the 
  

   Mahton 
  from 
  the 
  North, 
  Bidoung 
  hill 
  has 
  the 
  appearance 
  of 
  being 
  

   almost 
  isolated 
  from 
  the 
  main 
  body 
  of 
  the 
  Arakan 
  range, 
  so 
  much 
  so 
  

   that 
  it 
  is 
  not 
  clear, 
  at 
  the 
  distance 
  of 
  a 
  few 
  miles, 
  on 
  which 
  side 
  of 
  the 
  

   hill 
  the 
  Mahton 
  will 
  flow. 
  On 
  reaching, 
  however, 
  the 
  Northern 
  flank 
  

   of 
  Bidoung, 
  the 
  Mahton 
  turns 
  somewhat 
  to 
  the 
  East, 
  and 
  flows 
  through 
  

   a 
  gorge 
  of 
  serpentine 
  rock, 
  bare, 
  sterile, 
  and 
  picturesque, 
  with 
  Bidoung 
  

   on 
  the 
  right 
  and 
  a 
  somewhat 
  smaller 
  peak 
  of 
  similar 
  character 
  on 
  the 
  

   left. 
  The 
  serpentine 
  area 
  which 
  is 
  here 
  traversed 
  by 
  the 
  Mahton 
  

   extends 
  some 
  five 
  miles 
  in 
  a 
  North-by-east 
  or 
  North-north-east 
  direction, 
  

   with 
  a 
  mean 
  width 
  of 
  perhaps 
  two 
  miles 
  ; 
  and 
  in 
  addition 
  to 
  the 
  main 
  

   stretch 
  of 
  this 
  rock, 
  a 
  small 
  ridge 
  runs 
  down 
  from 
  it 
  along 
  the 
  East 
  bank 
  

   of 
  the 
  Mahton 
  to 
  nearly 
  opposite 
  the 
  village 
  of 
  Kaingi, 
  though 
  without 
  

   appearing 
  in 
  the 
  bed 
  of 
  the 
  river. 
  This 
  is 
  the 
  largest 
  single 
  mass 
  of 
  

   serpentine 
  in 
  the 
  province, 
  and 
  has 
  produced 
  greater 
  alteration 
  in 
  some 
  

   places 
  among 
  the 
  rocks 
  in 
  contact 
  with 
  it, 
  than 
  I 
  have 
  elsewhere 
  observed. 
  

   This 
  is 
  especially 
  the 
  case 
  on 
  the 
  flanks 
  of 
  Bidoung 
  hill, 
  where, 
  as 
  

   the 
  boundary 
  of 
  the 
  serpentine 
  is 
  approached, 
  the 
  rocks 
  for 
  a 
  short 
  

   distance 
  from 
  the 
  junction 
  become 
  converted 
  into 
  gneissose 
  and 
  chloritic 
  

   schists. 
  Even 
  here, 
  however, 
  this 
  effect 
  is 
  local, 
  and 
  is 
  much 
  less 
  visible 
  

   on 
  the 
  East 
  of 
  the 
  Mahton 
  along 
  the 
  minor 
  range 
  opposite 
  Kaingi 
  than 
  

   on 
  the 
  flanks 
  of 
  the 
  larger 
  mass 
  of 
  Bidoung. 
  I 
  think 
  it 
  probable, 
  how- 
  

   ever, 
  that 
  this 
  may 
  partly 
  be 
  due 
  to 
  the 
  composition 
  of 
  the 
  beds 
  in 
  con- 
  

   tact 
  with 
  the 
  serpentine 
  rather 
  than 
  to 
  any 
  more 
  occult 
  cause, 
  since, 
  

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