﻿20 
  FOOTE 
  : 
  GEOLOGY 
  OF 
  MADRAS. 
  

  

  The 
  country 
  on 
  the 
  west 
  side 
  of 
  the 
  Ennore-Puhcat 
  backwater 
  

   is 
  a 
  dead 
  flat 
  of 
  sandy 
  clay, 
  rather 
  swampy 
  in 
  some 
  places, 
  but 
  generally 
  

   dry 
  and 
  overgrown 
  with 
  Salsola, 
  which 
  extend 
  about 
  a 
  mile 
  inland. 
  

  

  Further 
  north, 
  the 
  bed 
  of 
  the 
  Pulicat 
  lake 
  is 
  composed 
  of 
  fluvio- 
  

  

  marine 
  beds, 
  abounding 
  most 
  especially 
  in 
  remains 
  

   Pulicat 
  lake. 
  

  

  of 
  Potamicles 
  flttviatile 
  and 
  Cytlierea 
  castanea. 
  

  

  The 
  surface 
  is 
  seen 
  at 
  low 
  water 
  to 
  consist 
  in 
  most 
  places 
  of 
  a 
  true 
  

  

  greyish-white 
  shell 
  marl. 
  

  

  h. 
  — 
  The 
  river 
  alluvia. 
  

  

  These 
  are 
  of 
  more 
  interest 
  than 
  the 
  unquestionably 
  marine 
  alluvium 
  

   along 
  the 
  coast, 
  as 
  their 
  peculiar 
  distribution 
  indicates 
  that 
  at 
  some 
  past 
  

   period, 
  but 
  within 
  the 
  human 
  era, 
  the 
  courses 
  pursued 
  by 
  various 
  of 
  the 
  

   principal 
  rivers 
  within 
  the 
  north-east 
  portion 
  of 
  the 
  area 
  of 
  sheet 
  78 
  

   differed 
  considerably 
  from 
  their 
  present 
  courses. 
  Thus, 
  it 
  will 
  be 
  seen 
  on 
  

   looking 
  at 
  the 
  map 
  that 
  the 
  Palar 
  river, 
  or 
  a 
  great 
  branch 
  of 
  it, 
  once 
  

   flowed 
  into 
  the 
  sea 
  not, 
  as 
  at 
  present, 
  a 
  few 
  miles 
  south 
  of 
  Sadras, 
  

   but 
  between 
  fifty 
  and 
  sixty 
  miles 
  further 
  north, 
  probably 
  near 
  to 
  the 
  

   present 
  embouchure 
  of 
  the 
  Corteliar 
  river. 
  

  

  The 
  broad 
  alluvial 
  valley 
  which 
  extends 
  from 
  the 
  sea 
  up 
  to 
  the 
  

  

  m 
  , 
  ,,, 
  „ 
  .',, 
  banks 
  of 
  the 
  present 
  Palar 
  river, 
  six 
  miles 
  east 
  

   The 
  old_ 
  valley 
  or 
  the 
  L 
  

  

  Palar 
  - 
  of 
  the 
  town 
  of 
  Arcot, 
  is 
  altogether 
  dispropor- 
  

  

  tioned 
  to 
  the 
  size 
  of 
  the 
  Corteliar 
  river, 
  which 
  now 
  flows 
  through 
  

   it, 
  and 
  it 
  is 
  evident 
  that 
  some 
  very 
  much 
  larger 
  river 
  was 
  instrumental 
  

   in 
  the 
  deposition 
  of 
  the 
  extensive 
  alluvial 
  formations 
  occupying 
  the 
  

   valley 
  in 
  question. 
  The 
  alluvial 
  accumulations 
  further 
  down 
  the 
  present 
  

   valley 
  of 
  the 
  Palar 
  are 
  equally 
  out 
  of 
  proportion 
  to 
  the 
  magnitude 
  of 
  

   the 
  river 
  now 
  debouching 
  at 
  Sadras. 
  

  

  A 
  stream 
  now 
  connected 
  with 
  the 
  Palar 
  near 
  Arcot 
  by 
  means 
  of 
  

   a 
  channel 
  which 
  is 
  crossed 
  by 
  the 
  Arconum-Conjeveram 
  tramway 
  

   at 
  Pulloor, 
  bears 
  the 
  Sanscrit 
  name 
  of 
  Virdachara 
  nuddee, 
  or 
  Old 
  Milk- 
  

   river, 
  and 
  is 
  regarded 
  by 
  the 
  natives 
  as 
  the 
  old 
  Palar, 
  the 
  Tamil 
  name 
  

   Palar 
  also 
  signifying 
  f 
  milk-river/ 
  

  

  ( 
  20 
  ) 
  

  

  