﻿PLIOCENE 
  EEKIOD 
  IX 
  ENGLAND. 
  66!) 
  

  

  land, 
  but 
  the 
  whole 
  of 
  them 
  (bl, 
  12. 
  b-3, 
  and 
  6') 
  representing 
  the 
  

   formation 
  of 
  the 
  sea 
  during 
  this 
  great 
  subsidence. 
  

  

  Further, 
  I 
  described 
  how 
  the 
  ice 
  of 
  the 
  Chalk}* 
  Ciay 
  at 
  its 
  

   greatest 
  extension 
  in 
  East 
  Anglia 
  (and 
  probably 
  as 
  the 
  first 
  step 
  in 
  

   the 
  general 
  recession 
  of 
  the 
  ice 
  of 
  the 
  great 
  glaciation), 
  by 
  receding 
  

   from 
  the 
  plateaux 
  and 
  uncovering 
  the 
  moraine 
  there 
  for 
  vegetation 
  

   to 
  spring 
  up 
  on 
  it, 
  but 
  still 
  occupying 
  the 
  valleys, 
  had 
  intercepted 
  

   the 
  drainage 
  from 
  the 
  plateaux, 
  and 
  so 
  given 
  rise 
  to 
  the 
  lagoon 
  

   deposit 
  of 
  Hoxne, 
  with 
  its 
  palaeolithic 
  implements, 
  mammalian 
  

   and 
  arboreal 
  remains 
  ; 
  and 
  how 
  this 
  deposit 
  had 
  been 
  denuded 
  by 
  

   the 
  effluent 
  water 
  proceeding 
  from 
  the 
  edge 
  of 
  the 
  ice 
  which 
  rested 
  

   on 
  the 
  high 
  land 
  of 
  Western 
  Xorfolk, 
  and 
  had 
  also 
  become 
  draped 
  with 
  

   the 
  finer 
  material 
  which 
  arose 
  from 
  the 
  washing-out 
  of 
  moraine 
  in 
  

   Xorth-west 
  Xorfolk 
  by 
  the 
  torrents 
  of 
  this 
  water 
  that 
  rolled 
  the 
  

   stones 
  in 
  it 
  into 
  the 
  cannon-shot 
  form. 
  Then, 
  after 
  describing 
  how, 
  in 
  

   such 
  valleys 
  of 
  East 
  Norfolk 
  and 
  Suffolk 
  as 
  had 
  at 
  the 
  time 
  of 
  this 
  

   recession 
  emerged, 
  much 
  of 
  the 
  gravel 
  in 
  them 
  was 
  formed 
  while 
  the 
  

   ice 
  was 
  vacating 
  them, 
  I 
  examined 
  and 
  traced 
  the 
  successive 
  emer- 
  

   gence 
  of 
  the 
  water-partings 
  between 
  the 
  drainage 
  flowing 
  to 
  the 
  Wash 
  

   and 
  that 
  flowing 
  to 
  the 
  Severn 
  (over 
  one 
  of 
  which, 
  that 
  between 
  the 
  

   Welland 
  and 
  Avon, 
  the 
  Lincolnshire 
  red-chalk 
  debris 
  had 
  been 
  

   carried 
  into 
  the 
  basin 
  of 
  the 
  Severn 
  system), 
  as 
  well 
  as 
  of 
  the 
  part- 
  

   ings 
  between 
  the 
  drainage 
  flowing 
  to 
  the 
  Severn 
  and 
  that 
  flowing 
  to 
  

   the 
  Thames. 
  

  

  In 
  all 
  this 
  the 
  main 
  feature 
  for 
  my 
  guidance 
  was 
  that 
  great 
  incre- 
  

   ment 
  of 
  depression 
  westwards 
  and 
  southwards, 
  the 
  recovery 
  from 
  

   which 
  has 
  so 
  complicated 
  the 
  problem 
  which 
  I 
  am 
  endeavouring 
  to 
  

   work 
  out. 
  but 
  which 
  gave 
  rise 
  to 
  phenomena 
  in 
  no 
  way 
  analogous 
  to 
  

   a 
  renewal 
  of 
  those 
  which 
  accompanied 
  the 
  progress 
  of 
  the 
  depression, 
  

   because 
  during 
  that 
  recovery, 
  and 
  before 
  even 
  the 
  larger 
  part 
  of 
  this 
  

   had 
  been 
  accomplished, 
  the 
  major 
  glaciation 
  had 
  begun 
  to 
  diminish 
  in 
  

   its 
  intensity. 
  These 
  phenomena 
  I 
  now 
  proceed 
  to 
  trace. 
  ■ 
  

  

  The 
  rivers, 
  other 
  than 
  those 
  of 
  Lincolnshire, 
  Xorfolk, 
  and 
  Xorth 
  

   Suffolk, 
  which 
  flow 
  to 
  the 
  Wash 
  are 
  the 
  Welland, 
  Xen, 
  Great 
  Ouse, 
  and 
  

   Cam 
  ; 
  and 
  their 
  valleys, 
  though 
  modified 
  by 
  the 
  land-ice 
  as 
  far 
  as 
  this 
  

   extended, 
  having 
  been 
  in 
  existence 
  before 
  submergence 
  began, 
  the 
  

   partings 
  which 
  now 
  divide 
  the 
  drainage 
  flowing 
  through 
  them 
  to 
  the 
  

   Wash 
  from 
  that 
  flowing 
  southwards 
  to 
  the 
  Thames, 
  or 
  westwards 
  to 
  the 
  

   Severn, 
  became 
  by 
  this 
  increment 
  of 
  depression 
  lowered 
  relatively 
  

   to 
  their 
  Wash 
  extremity, 
  while 
  they 
  were 
  elevated 
  relatively 
  to 
  the 
  

   southern 
  and 
  western 
  extremities 
  of 
  the 
  valleys 
  of 
  the 
  Thames 
  and 
  

   Severn 
  systems. 
  Thus 
  the 
  sea 
  which, 
  from 
  the 
  westerly 
  and 
  southerly 
  

   increment 
  of 
  depression, 
  still 
  covered 
  all 
  but 
  the 
  highest 
  elevations 
  

   of 
  the 
  Thames 
  and 
  Severn 
  sj*stems, 
  had 
  access 
  to 
  these 
  four 
  Wash 
  

   valleys 
  from 
  the 
  west; 
  while 
  what 
  is 
  now 
  the 
  seaward 
  extremity 
  of 
  

   these 
  four 
  valleys 
  was 
  blocked 
  by 
  the 
  ice, 
  which, 
  though 
  in 
  retreat, 
  

   still 
  continued 
  in 
  mass 
  over 
  Lincolnshire, 
  and 
  thence 
  northwards 
  to 
  

   the 
  Pennine. 
  "While 
  this 
  was 
  so 
  with 
  the 
  Welland, 
  Xen, 
  (ireat- 
  

   Ouse, 
  and 
  Cam 
  valleys, 
  the 
  Little-Ouse 
  and 
  Lark 
  rivers 
  had, 
  by 
  the 
  

   emergence 
  of 
  Xorfolk 
  and 
  Xorth 
  Suffolk, 
  come 
  into 
  existence, 
  and 
  

  

  