﻿COKKELATION 
  OF 
  THE 
  BOURNEMOUTH 
  BEDS. 
  O 
  

  

  The 
  sequence 
  of 
  beds 
  deposited 
  by 
  river-action 
  is, 
  it 
  is 
  well 
  known, 
  

   rather 
  horizontal 
  than 
  vertical, 
  the 
  sediments 
  nearest 
  the 
  head 
  of 
  

   any 
  valley 
  that 
  has 
  been 
  silted 
  up 
  being 
  usually 
  the 
  oldest. 
  To 
  

   take 
  a 
  familiar 
  instance, 
  the 
  plains 
  of 
  the 
  Rhone 
  above 
  Lake 
  Leman, 
  

   were 
  doubtless 
  once 
  a 
  portion 
  of 
  the 
  lake 
  progressively 
  filled 
  in 
  ; 
  and 
  

   if 
  sections 
  through 
  them 
  were 
  now 
  visible, 
  these 
  would 
  present 
  many 
  

   miles 
  of 
  horizontal 
  stratification, 
  only 
  cut 
  through 
  and 
  disturbed 
  

   near 
  the 
  surface 
  by 
  the 
  subsequent 
  shifts 
  in 
  the 
  course 
  of 
  the 
  river 
  : 
  

   yet 
  though 
  continuous 
  and 
  horizontal, 
  the 
  sediments 
  in 
  the 
  upper 
  

   part 
  of 
  the 
  valley 
  are, 
  of 
  course, 
  enormously 
  older 
  than 
  those 
  forming 
  

   at 
  the 
  present 
  outfall 
  of 
  the 
  river 
  into 
  the 
  lake. 
  There 
  are 
  many 
  

   indications 
  that 
  the 
  Eocene 
  river 
  which 
  deposited 
  the 
  Bournemouth 
  

   strata 
  flowed 
  from 
  a 
  westerly 
  point 
  ; 
  and 
  therefore 
  the 
  western 
  ex- 
  

   tremity 
  of 
  the 
  cliff-section 
  is 
  inferred 
  to 
  be 
  the 
  oldest. 
  Moreover 
  

   close 
  examination 
  reveals 
  that 
  the 
  clays, 
  sands, 
  and 
  grits, 
  which 
  do 
  

   not 
  appear 
  at 
  first 
  traceable 
  for 
  more 
  than 
  a 
  few 
  yards, 
  are 
  really 
  

   often 
  in 
  parallel 
  zones 
  of 
  some 
  extent, 
  and 
  repose 
  at 
  an 
  angle 
  which 
  

   exposes 
  at 
  least 
  400 
  feet 
  of 
  their 
  thickness. 
  

  

  It 
  is 
  scarcely 
  necessary 
  to 
  describe 
  the 
  somewhat 
  complicated 
  

   formation 
  of 
  the 
  cliffs 
  in 
  minute 
  detail. 
  Their 
  general 
  appearance 
  

   seaward 
  is 
  that 
  of 
  a 
  confused 
  mass 
  of 
  lenticular 
  patches, 
  now 
  of 
  sand, 
  

   and 
  now 
  of 
  light- 
  or 
  dark-coloured 
  clay, 
  suggesting 
  forcibly 
  a 
  trans- 
  

   verse 
  or 
  oblique 
  section 
  across 
  an 
  old 
  river-valley. 
  The 
  sections 
  up 
  

   the 
  chines 
  do 
  not 
  present 
  the 
  same 
  lens-shaped 
  patches, 
  but 
  more 
  

   continuous 
  beds; 
  and 
  it 
  may 
  therefore 
  be 
  assumed 
  that 
  they 
  are 
  

   somewhat 
  more 
  in 
  the 
  direction 
  of 
  the 
  former 
  channels. 
  

  

  The 
  cliffs 
  fronting 
  the 
  sea 
  may 
  be 
  divided 
  into 
  three 
  groups, 
  which 
  

   are 
  not 
  difficult 
  to 
  distinguish 
  when 
  unobscured 
  by 
  blown 
  sand 
  or 
  debris. 
  

   From 
  Poole 
  Harbour 
  to 
  Bateman's 
  Chine 
  there 
  are 
  masses 
  of 
  dark 
  

   clay 
  enclosed 
  in 
  the 
  sands. 
  The 
  principal 
  mass 
  is 
  1100 
  feet 
  long 
  

   and 
  about 
  35 
  feet 
  above 
  high 
  water. 
  It 
  consists 
  of 
  a 
  continuous 
  

   band, 
  4 
  feet 
  thick, 
  of 
  yellowish 
  sandy 
  clay, 
  overlain 
  by 
  darker 
  clay 
  

   of 
  varying 
  thickness, 
  and 
  attaining 
  40 
  feet 
  at 
  its 
  eastern 
  end. 
  It 
  

   terminates 
  in 
  the 
  chine, 
  and 
  is 
  barely 
  traceable 
  across 
  to 
  the 
  other 
  

   side. 
  At 
  the 
  base 
  of 
  this 
  dark 
  clay 
  there 
  are 
  in 
  several 
  places 
  

   lighter 
  clay 
  patches 
  containing 
  leaves, 
  the 
  most 
  important 
  being 
  

   situated 
  at 
  about 
  100 
  yards 
  to 
  the 
  west 
  of 
  the 
  chine 
  just 
  mentioned. 
  

   The 
  exact 
  section 
  is 
  : 
  — 
  

  

  ft. 
  in. 
  

   Gravel, 
  a 
  few 
  feet 
  

  

  Cross-bedded 
  coarse 
  sands 
  with 
  rolled 
  pipe-clay 
  12 
  

  

  Marly 
  white 
  clays, 
  unstra 
  tilled, 
  with 
  a 
  layer 
  of 
  bright 
  yellow 
  sand 
  4 
  

   Slate-coloured 
  clay, 
  with 
  frequent 
  layers 
  of 
  pyrites 
  towards 
  the 
  

  

  base 
  11 
  

  

  Black 
  clay 
  with 
  leaves 
  6 
  

  

  Shading 
  to 
  fawn-coloured 
  clay 
  with 
  leaves 
  6 
  

  

  Regularly 
  stratified 
  yellowish 
  and 
  white 
  sand 
  alternating 
  with 
  

  

  pinkish 
  sandy 
  clay. 
  (This 
  bed 
  is 
  continuous 
  for 
  1100 
  feet.). 
  . 
  . 
  4 
  

  

  White 
  and 
  buff 
  sands 
  25 
  

  

  Black 
  clays, 
  often 
  obliquely, 
  sometimes 
  vertically 
  bedded, 
  usually 
  con- 
  

   cealed 
  by 
  debris. 
  

  

  The 
  prevailing 
  leaves 
  are 
  simple 
  and 
  either 
  laurel-like 
  or 
  willow- 
  

   like, 
  and 
  frequently 
  attached 
  in 
  numbers 
  to 
  the 
  twigs. 
  A 
  large 
  

  

  