﻿TRAP. 
  2 
  3 
  

  

  clusively 
  proving 
  the 
  appearance 
  in 
  question 
  to 
  be 
  merely 
  the 
  result 
  of 
  

   the 
  peculiar 
  arrangements 
  of 
  the 
  component 
  minerals." 
  1 
  

  

  The 
  rock 
  occupying 
  the 
  hollow, 
  or 
  valley, 
  between 
  the 
  central 
  peak 
  

   Decomposed 
  quartz- 
  of 
  Girnar 
  and 
  the 
  surrounding 
  ranges, 
  is 
  a 
  third 
  

   diorite 
  in 
  the 
  valley. 
  variety 
  of 
  the 
  diorite, 
  consisting 
  of 
  a 
  granular 
  

  

  mixture 
  of 
  felspar 
  and 
  hornblende, 
  the 
  latter 
  in 
  fair 
  proportion 
  ; 
  with 
  free 
  

   quartz 
  and 
  a 
  sparing 
  addition 
  of 
  rusty 
  black 
  mica. 
  This 
  variety 
  is 
  

   remarkably 
  prone 
  to 
  decomposition, 
  and 
  at 
  first 
  sight 
  much 
  resembles 
  

   decomposed 
  gneiss 
  ; 
  it 
  is 
  only 
  in 
  the 
  small 
  lenticular 
  masses, 
  which 
  have 
  

   escaped 
  decomposition, 
  that 
  the 
  true 
  nature 
  of 
  the 
  rock 
  can 
  be 
  detected, 
  

   its 
  usual 
  condition 
  being 
  that 
  of 
  a 
  friable 
  mass, 
  which 
  crumbles 
  on 
  

   handling. 
  

  

  The 
  surrounding, 
  or 
  outward 
  annular, 
  ranges 
  are 
  composed 
  mostly 
  of 
  

  

  Greenstones 
  of 
  the 
  various 
  greenstones, 
  to 
  which 
  it 
  is 
  not 
  easy 
  (with- 
  

   outer 
  ranges. 
  QU 
  ^. 
  a 
  c 
  i 
  ose 
  s 
  t 
  u 
  dy 
  w 
  ith 
  microscopic 
  sections) 
  to 
  

  

  assign 
  specific 
  names. 
  Some 
  are 
  felsitic, 
  very 
  tough 
  and 
  compact 
  ; 
  others 
  

   are 
  basaltic, 
  with 
  much 
  olivine 
  : 
  free 
  quartz 
  is 
  not 
  uncommon 
  in 
  a 
  few. 
  

   These 
  rocks 
  seldom 
  present 
  either 
  the 
  bedded 
  structure, 
  or 
  the 
  terraced 
  

   appearance, 
  of 
  ordinary 
  trap-flows, 
  so 
  commonly 
  seen 
  in 
  other 
  parts 
  of 
  

   the 
  district. 
  Yet 
  some 
  of 
  the 
  greenstones 
  appear 
  to 
  slope 
  almost 
  as 
  

   steeply 
  as 
  the 
  hill-side 
  ; 
  while 
  a 
  general 
  outward, 
  or 
  quaquaversal, 
  incli- 
  

  

  Quartz-felsite 
  along 
  nation 
  is 
  perceptible 
  throughout 
  the 
  annular 
  ranges, 
  

   the 
  axis. 
  rp^ 
  ax 
  j 
  s 
  £ 
  ^ 
  e 
  wes 
  tern 
  range, 
  which 
  is 
  very 
  steep, 
  

  

  and 
  crested 
  with 
  a 
  precipitous 
  jagged 
  ridge, 
  consists 
  of 
  an 
  extremely 
  

   tough 
  and 
  durable 
  quartz 
  -felsite, 
  containing 
  plagioclase, 
  quartz, 
  and 
  

   magnetite 
  in 
  a 
  micro-crystalline 
  base. 
  2 
  It 
  has 
  the 
  form 
  of 
  a 
  huge 
  dyke, 
  

   or 
  vertical 
  intrusion. 
  On 
  the 
  west 
  flank 
  of 
  this 
  western 
  range 
  is 
  a 
  bluff 
  

   of 
  rock, 
  which 
  assumes 
  the 
  aspect 
  of 
  gneiss, 
  especially 
  in 
  its 
  mode 
  of 
  

   weathering; 
  but 
  a 
  microscopic 
  examination 
  of 
  a 
  thin 
  section 
  shows 
  it 
  

   to 
  be 
  a 
  finely-granular 
  quartz-felsite. 
  

  

  1 
  Mr. 
  Theobald's 
  manuscript 
  written 
  in 
  1858. 
  

  

  3 
  The 
  "Asoka 
  stone," 
  as 
  it 
  is 
  called, 
  on 
  the 
  polished 
  surface 
  of 
  which 
  is 
  engraved 
  the 
  

   celebrated 
  edict 
  of 
  Aspka 
  (B.C. 
  250), 
  is 
  a 
  rounded 
  boulder-like 
  mass 
  of 
  this 
  rock. 
  

  

  ( 
  95 
  ) 
  

  

  