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  PROF. 
  J. 
  PRESIWICH 
  OS 
  IKE 
  OCCURRENCE 
  OF 
  

  

  Heath, 
  we 
  must 
  assume 
  that 
  the 
  chalk-escarpment, 
  as 
  Dr. 
  Evans 
  

   had 
  stated, 
  did 
  not 
  occupy 
  its 
  present 
  place, 
  so 
  that 
  not 
  only 
  had 
  

   a 
  considerable 
  valley 
  been 
  excavated 
  by 
  small 
  streams, 
  but 
  the 
  

   chalk-escarpment 
  had 
  itself 
  receded 
  considerably 
  more 
  than 
  a 
  mile. 
  

  

  He 
  had 
  found 
  a 
  flake 
  in 
  a 
  gravel-pit 
  at 
  East 
  Mailing 
  Heath 
  25 
  

   years 
  ago, 
  at 
  a 
  time 
  when 
  nothing 
  of 
  the 
  kind 
  was 
  known 
  in 
  the 
  

   district 
  ; 
  this 
  gravel 
  lies 
  300 
  feet 
  above 
  the 
  Medway. 
  It 
  occurred 
  

   to 
  him 
  that 
  many 
  of 
  the 
  implements 
  lying 
  on 
  the 
  chalk 
  might 
  

   originally 
  have 
  been 
  dropped 
  there. 
  

  

  Whatever 
  might 
  be 
  the 
  origin 
  of 
  the 
  gravels 
  on 
  the 
  Lower 
  Green- 
  

   sand 
  on 
  the 
  watershed, 
  it 
  is 
  certain 
  that 
  one 
  could, 
  in 
  the 
  Wealden 
  

   area, 
  work 
  out 
  with 
  extreme 
  accuracy 
  the 
  relationship 
  of 
  the 
  

   ordinary 
  gravels 
  to 
  the 
  beds 
  from 
  which 
  they 
  had 
  been 
  derived 
  : 
  of 
  

   this 
  he 
  gave 
  examples, 
  showing 
  how 
  one 
  could 
  sometimes 
  even 
  trace 
  

   the 
  point 
  of 
  junction 
  of 
  two 
  streams 
  flowing 
  over 
  beds 
  of 
  different 
  

   lithological 
  characters, 
  and 
  so 
  bringing 
  down 
  different 
  materials. 
  

  

  He 
  described 
  the 
  general 
  distribution 
  of 
  the 
  gravels 
  in 
  the 
  north- 
  

   eastern 
  part 
  of 
  the 
  AVealden 
  area, 
  showing 
  from 
  their 
  composition 
  

   that 
  they 
  were 
  formed 
  by 
  streams 
  flowing 
  in 
  the 
  same 
  general 
  

   direction 
  as 
  the 
  existing 
  streams 
  : 
  the 
  gravels 
  on 
  the 
  east 
  and 
  west 
  

   sides 
  of 
  the 
  Medway- 
  ; 
  * 
  gorge 
  " 
  through 
  the 
  Greensand-escarpment, 
  

   and 
  also 
  on 
  the 
  east 
  and 
  west 
  sides 
  of 
  the 
  Stour-' 
  ; 
  gorge 
  " 
  through 
  

   the 
  chalk-escarpment, 
  differ 
  so 
  widely 
  in 
  character, 
  that 
  they 
  cannot 
  

   be 
  explained 
  by 
  any 
  old 
  river 
  flowing 
  from 
  west 
  to 
  east. 
  

  

  Dr. 
  Hicrs 
  was 
  not 
  acquainted 
  with 
  the 
  district, 
  but 
  the 
  Author 
  

   had 
  brought 
  forward 
  evidence 
  which 
  it 
  was 
  extremely 
  difficult 
  for 
  

   those 
  who 
  still 
  contended 
  against 
  the 
  glacial 
  or 
  preglacial 
  age 
  of 
  Man 
  

   in 
  Britain 
  to 
  overcome. 
  He 
  asked 
  why 
  the 
  implements 
  on 
  the 
  

   upper 
  ridges 
  were 
  rolled. 
  He 
  believed 
  that 
  at 
  the 
  time 
  they 
  were 
  

   deposited 
  the 
  country 
  formed 
  a 
  plain, 
  and 
  that 
  the 
  evidence 
  pointed 
  

   to 
  floods 
  coming 
  from 
  melting 
  ice. 
  

  

  Mr. 
  ^Vhitaker 
  commented 
  on 
  the 
  number 
  of 
  implements 
  as 
  indi- 
  

   cating 
  a 
  populous 
  condition 
  of 
  our 
  country. 
  He 
  also 
  insisted 
  on 
  

   the 
  importance 
  of 
  collecting 
  implements 
  in 
  all 
  states 
  of 
  imperfection. 
  

   Great 
  caution 
  was 
  needed 
  in 
  attempting 
  to 
  correlate 
  the 
  Drifts 
  of 
  

   Southern 
  England 
  with 
  those 
  of 
  other 
  areas. 
  There 
  was 
  no 
  evidence 
  

   of 
  the 
  existence 
  of 
  Glacial 
  Drift 
  south 
  of 
  the 
  Thames, 
  though 
  such 
  

   occurred 
  immediately 
  to 
  the 
  north 
  of 
  it. 
  A 
  large 
  number 
  of 
  the 
  

   41 
  finds 
  '" 
  occurred 
  on 
  the 
  surface, 
  which 
  materially 
  altered 
  the 
  evi- 
  

   dence 
  furnished 
  by 
  them. 
  One 
  could 
  not 
  argue 
  as 
  to 
  the 
  age 
  of 
  an 
  

   implement, 
  unless 
  found 
  in 
  gravel. 
  AVhen 
  the 
  chalk-escarpment 
  

   occurred 
  at 
  a 
  higher 
  level 
  southward, 
  the 
  springs 
  would 
  also 
  be 
  

   higher. 
  He 
  was 
  glad 
  to 
  have 
  heard 
  the 
  Author 
  refer 
  to 
  gravels 
  of 
  

   doubtful 
  age 
  and 
  origin 
  ; 
  there 
  were 
  many 
  such, 
  in 
  some 
  of 
  which 
  

   he 
  would 
  be 
  much 
  surprised 
  to 
  find 
  implements. 
  That 
  at 
  Swans- 
  

   combe 
  Wood 
  was 
  probably 
  older 
  than 
  the 
  Boulder-clay, 
  though 
  

   whether 
  older 
  than 
  other 
  glacial 
  deposits 
  he 
  could 
  not 
  say. 
  The 
  

   term 
  " 
  preglacial'* 
  had 
  been 
  used 
  very 
  vaguely, 
  was 
  objectionable, 
  

   and 
  ought 
  to 
  be 
  dropped. 
  

  

  