﻿92 
  THEOBALD 
  : 
  GEOLOGY 
  OF 
  PEGU. 
  

  

  breadth 
  diminishes 
  to 
  eleven 
  miles,, 
  but 
  soon 
  again 
  widens 
  to 
  fourteen 
  

   iniles, 
  whence 
  it 
  again 
  decreases, 
  till 
  at 
  the 
  Thalaydan 
  stream 
  the 
  breadth 
  

   is 
  only 
  one 
  and 
  a 
  half 
  mile, 
  this 
  diminution 
  being 
  partly 
  produced 
  by 
  

   the 
  outcurving 
  of 
  the 
  beds 
  to 
  the 
  East, 
  and 
  the 
  denudation 
  by 
  the 
  

   river 
  they 
  have 
  thereby 
  been 
  subjected 
  to. 
  Still 
  going 
  South, 
  the 
  

   breadth 
  increases 
  somewhat, 
  and 
  at 
  Akouktoung, 
  the 
  celebrated 
  carved 
  

   rocks 
  four 
  miles 
  below 
  the 
  Thalaydan 
  stream, 
  the 
  group 
  is 
  four 
  miles 
  

   broad. 
  South 
  of 
  Myanoung 
  the 
  extent 
  of 
  the 
  group 
  becomes 
  some- 
  

   what 
  irregular 
  and 
  uncertain, 
  being 
  covered 
  and 
  masked 
  on 
  the 
  East 
  

   by 
  a 
  thick 
  deposit 
  of 
  sand 
  and 
  gravel; 
  while 
  on 
  the 
  West 
  its 
  extent 
  

   cannot 
  be 
  satisfactorily 
  defined, 
  from 
  the 
  ambiguity 
  attaching 
  to 
  the 
  

   altered 
  rocks 
  of 
  the 
  Negrais 
  group, 
  and 
  the 
  difficulty 
  of 
  separating 
  them 
  

   from 
  the 
  Nummulitics. 
  

  

  I 
  must 
  now 
  preface 
  my 
  remarks 
  on 
  the 
  geology 
  of 
  Western 
  Prome 
  

   by 
  a 
  brief 
  sketch 
  of 
  its 
  main 
  physical 
  features, 
  as 
  an 
  intimate 
  con- 
  

   nexion 
  subsists 
  between 
  the 
  geology 
  of 
  the 
  district 
  and 
  the 
  physi- 
  

   cal 
  arrangement 
  of 
  its 
  surface. 
  This 
  is 
  well 
  seen 
  in 
  many 
  places, 
  and 
  

   could 
  be 
  readily 
  enough 
  detected 
  on 
  a 
  good 
  map, 
  but 
  the 
  orographical 
  

   details 
  of 
  our 
  only 
  map 
  are 
  so 
  inadequately 
  given, 
  as 
  to 
  mislead 
  the 
  eye 
  

   and 
  render 
  necessary 
  a 
  somewhat 
  tedious 
  review 
  of 
  the 
  chief 
  points 
  in 
  

   question. 
  Western 
  Prome 
  viewed 
  from 
  across 
  the 
  Irrawadi 
  presents 
  

   the 
  appearance 
  of 
  an 
  undulating 
  country 
  covered 
  with 
  low 
  hills, 
  with 
  

   a 
  few 
  hills 
  distinctly 
  more 
  prominent 
  than 
  the 
  rest 
  from 
  amidst 
  which 
  

   they 
  rise 
  in 
  quasi 
  isolation. 
  Prominent 
  among 
  these 
  is 
  the 
  so-called 
  

   Lime-hill 
  below 
  Thaietmio, 
  a 
  mass 
  of 
  Nummulitic 
  strata 
  forced 
  up 
  

   through 
  the 
  newer 
  Tertiaries, 
  and 
  forming 
  a 
  conspicuous 
  landmark 
  for 
  

   the 
  district. 
  Towards 
  the 
  frontier 
  there 
  is 
  also 
  a 
  very 
  prominent 
  range, 
  

   which 
  crossing 
  it 
  about 
  three 
  miles 
  west 
  of 
  the 
  river, 
  extends 
  down 
  to 
  

   within 
  some 
  six 
  miles 
  of 
  Thaietmio, 
  where 
  it 
  terminates. 
  To 
  the 
  West- 
  

   ward, 
  higher 
  ranges 
  are 
  seen, 
  but 
  at 
  this 
  distance 
  their 
  arrangement 
  is 
  

   not 
  clearly 
  made 
  out. 
  I 
  shall 
  presently 
  show 
  how 
  along 
  this 
  distant 
  

  

  ( 
  2S0 
  ) 
  

  

  