﻿22 
  F00TE 
  : 
  GEOLOGY 
  OF 
  MADRAS. 
  

  

  District. 
  It 
  rarely 
  contains 
  beds 
  of 
  loam 
  and 
  still 
  more 
  rarely 
  of 
  clay. 
  

   The 
  latter 
  formation 
  was 
  observed 
  only 
  between 
  Chingleput 
  and 
  the 
  sea 
  in 
  

   two 
  or 
  three 
  places, 
  where 
  the 
  ground 
  was 
  in 
  consequence 
  very 
  swampy. 
  

   Between 
  Sadras 
  and 
  the 
  village 
  of 
  Perumbaukum 
  (two 
  and 
  half 
  miles 
  

   west 
  of 
  Sadras) 
  the 
  clay 
  is 
  of 
  dark 
  -greyish 
  black 
  color, 
  and 
  near 
  the 
  

   bank 
  of 
  a 
  deep 
  but 
  narrow 
  branch 
  of 
  the 
  river 
  shows 
  the 
  characters 
  

   of 
  true 
  regur, 
  or 
  cotton 
  soil. 
  

  

  The 
  description 
  of 
  the 
  alluvium 
  of 
  the 
  Palar 
  river 
  applies 
  equally 
  

  

  * 
  .t 
  ,j 
  well 
  to 
  that 
  of 
  the 
  old 
  Palar 
  valley, 
  through 
  the 
  

   Alluvium 
  of 
  the 
  old 
  Ji 
  & 
  

  

  Palar. 
  deposits 
  of 
  which 
  the 
  present 
  Corteliar 
  river, 
  

  

  after 
  draining 
  the 
  great 
  Covrepauk 
  tank, 
  merely 
  cuts 
  its 
  way, 
  very 
  

   rarely 
  farming 
  any 
  deposit 
  itself. 
  

  

  The 
  deposits 
  of 
  the 
  Corteliar 
  river 
  are 
  easily 
  distinguishable 
  from 
  

   the 
  coarse 
  sandy 
  alluvium 
  of 
  the 
  old 
  Palar, 
  which 
  

  

  CorE 
  1 
  ™ 
  ° 
  f 
  tbC 
  is 
  of 
  P 
  ale 
  drab 
  colour 
  in 
  g 
  eneral 
  ; 
  whereas 
  the 
  

   Corteliar 
  has 
  deposited 
  but 
  a 
  very 
  narrow 
  

   belt 
  of 
  reddish 
  loam 
  or 
  loamy 
  sands 
  on 
  the 
  sloping 
  sides 
  of 
  the 
  old 
  

   and 
  rather 
  deep 
  bed. 
  The 
  principal 
  deposition 
  of 
  such 
  loamy 
  alluvium 
  

   has 
  taken 
  place 
  between 
  Illeputandalum 
  and 
  Tukkoolum 
  (Tukkool 
  of 
  

   Atlas 
  sheet) 
  . 
  

  

  On 
  the 
  east 
  side 
  of 
  the 
  bridge 
  by 
  which 
  the 
  Arconum-Conjeveram 
  

   tramway 
  crosses 
  the 
  river, 
  the 
  relative 
  position 
  and 
  the 
  small 
  extent 
  

   of 
  the 
  true 
  Corteliar 
  alluvium 
  can 
  be 
  especially 
  well 
  seen. 
  Follow- 
  

   in^ 
  the 
  course 
  of 
  the 
  valley 
  seawards 
  in 
  a 
  north-east 
  direction, 
  the 
  alluvi- 
  

   um 
  will 
  be 
  found 
  to 
  surround 
  several 
  outliers 
  of 
  later- 
  

   Junction 
  of 
  the 
  old 
  . 
  

   Pular 
  and 
  Poonamallee 
  itic 
  rocks 
  near 
  the 
  Trivellore 
  railway 
  station, 
  

  

  while 
  a 
  narrow 
  strip 
  of 
  alluvium 
  follows 
  the 
  

   course 
  of 
  the 
  Cuum 
  or 
  Madias 
  river 
  and 
  joins 
  the 
  alluvium 
  of 
  the 
  old 
  

   Palar 
  with 
  the 
  sandy 
  alluvium 
  of 
  the 
  Poonamallee 
  bay 
  .* 
  

  

  * 
  The 
  branch 
  stream 
  which 
  runs 
  from 
  the 
  Cuum 
  river 
  into 
  the 
  great 
  Chuui- 
  

   brumbaucum 
  tank 
  is 
  of 
  artificial 
  origin. 
  

  

  ( 
  M 
  ) 
  

  

  