﻿PLIOCENE 
  PERIOD 
  IN 
  ENGLAND. 
  685 
  

  

  sea 
  thus 
  covering 
  the 
  Basement 
  Clay, 
  B, 
  and 
  the 
  ice 
  which 
  enveloped 
  

   the 
  eastern 
  moorlands 
  as 
  not 
  yet 
  extended 
  down 
  the 
  east 
  of 
  the 
  Wold 
  ; 
  

   though 
  probably 
  it 
  had 
  begun 
  thus 
  to 
  extend, 
  and 
  to 
  take 
  the 
  place 
  of 
  

   the 
  Basement 
  Clay 
  ice, 
  by 
  the 
  time 
  that 
  the 
  depression 
  culminated. 
  

   It 
  was 
  the 
  same 
  change 
  of 
  inclination, 
  causing 
  the 
  ice 
  of 
  the 
  

   Basement-Clay 
  to 
  retire 
  to 
  the 
  west 
  of 
  the 
  Wold, 
  that 
  caused 
  the 
  

   East-Moorland 
  ice 
  (which 
  had 
  heretofore 
  taken 
  an 
  easterly 
  direc- 
  

   tion 
  like 
  that 
  of 
  the 
  Wold-ice) 
  to 
  take 
  a 
  southerly 
  direction, 
  and, 
  

   hugging 
  the 
  eastern 
  slope 
  of 
  the 
  Yorkshire 
  Wold, 
  to 
  take 
  the 
  

   place 
  over 
  Holderness 
  of 
  the 
  Basement-Clay 
  ice 
  which 
  had 
  thus 
  

   retired 
  through 
  the 
  Humber 
  ; 
  and 
  this 
  ice, 
  bringing 
  with 
  it 
  the 
  

   Shap 
  blocks, 
  which 
  had 
  crossed 
  the 
  Pennine 
  into 
  the 
  valley 
  of 
  

   the 
  Tees, 
  originated 
  the 
  Purple 
  Clay 
  (D). 
  Thus 
  this 
  clay, 
  D, 
  is 
  

   spread 
  over 
  a 
  Basement-Clay 
  moraine 
  corresponding 
  to 
  that 
  of 
  

   Holderness, 
  which 
  occupies 
  the 
  preglacial 
  valley 
  of 
  Pickering, 
  in 
  

   precisely 
  the 
  same 
  way 
  as 
  it 
  is 
  over 
  that 
  of 
  Holderness, 
  which 
  

   occupies 
  the 
  preglacial 
  valley 
  of 
  the 
  Humber; 
  and 
  just 
  as 
  the 
  edge 
  

   of 
  the 
  one 
  Basement 
  Clay 
  lying 
  against 
  the 
  chalk 
  side 
  of 
  the 
  Old 
  

   Humber 
  valley, 
  as 
  this 
  rises 
  above 
  the 
  beach-line 
  north 
  of 
  Brid- 
  

   lington, 
  is 
  overspread 
  and 
  overlapped 
  by 
  the 
  Purple 
  Clay, 
  so 
  is 
  the 
  

   edge 
  of 
  the 
  other 
  Basement 
  Clay 
  lying 
  against 
  the 
  oolitic 
  rockside 
  of 
  

   the 
  old 
  Pickering 
  valley, 
  as 
  this 
  rises 
  from 
  below 
  the 
  beach-line 
  north 
  

   of 
  Pile}', 
  overspread 
  and 
  overlapped 
  by 
  the 
  Purple 
  Clay 
  also. 
  My 
  

   personal 
  knowledge 
  of 
  the 
  coast-section 
  northwards 
  ceases 
  at 
  Scar- 
  

   borough 
  ; 
  but 
  I 
  am 
  informed 
  by 
  Mr. 
  Barrow, 
  of 
  the 
  Geol. 
  Survey, 
  

   that 
  the 
  valleys 
  of 
  the 
  coast 
  side 
  of 
  the 
  East 
  Moorlands 
  between 
  

   Scarborough 
  and 
  the 
  Tees 
  mouth, 
  such 
  as 
  that 
  of 
  the 
  Esk 
  at 
  Whitby 
  

   and 
  that 
  at 
  Eunswick, 
  are 
  similarly 
  filled 
  by 
  a 
  Basement 
  Clay 
  and 
  

   an 
  Upper 
  Clay 
  ; 
  and 
  I 
  infer 
  (especially 
  since, 
  as 
  mentioned 
  in 
  

   describing 
  Stage 
  VIL, 
  nothing 
  corresponding 
  to 
  the 
  Hessle 
  Clay 
  

   occurs 
  along 
  the 
  coast-section, 
  from 
  the 
  place 
  of 
  fig. 
  L. 
  to 
  Scar- 
  

   borough) 
  that 
  all 
  this 
  Basement 
  Clay 
  is. 
  like 
  that 
  of 
  Holderness 
  

   and 
  Filey, 
  the 
  moraine 
  of 
  the 
  ice 
  before 
  the 
  change 
  in 
  incli- 
  

   nation 
  had 
  caused 
  it 
  to 
  change 
  the 
  direction 
  of 
  its 
  movement, 
  

   and 
  so 
  give 
  rise 
  to 
  the 
  Purple 
  Clay 
  which 
  overlies 
  it. 
  Having 
  

   thus 
  originated 
  in 
  a 
  similar 
  deflection 
  of 
  the 
  ice 
  from 
  the 
  same 
  

   change 
  of 
  inclination 
  that 
  gave 
  rise 
  to 
  the 
  Chalky 
  Clay, 
  the 
  Purple 
  

   Clay 
  is 
  probably 
  coeval 
  with 
  the 
  whole, 
  instead 
  of 
  only 
  the 
  latter 
  

   part 
  of 
  this, 
  as 
  suggested 
  in 
  the 
  first 
  part 
  of 
  this 
  memoir, 
  though, 
  

   from 
  the 
  position 
  and 
  source 
  of 
  the 
  respective 
  ice-streams 
  from 
  

   which 
  these 
  clays 
  originated, 
  the 
  Purple 
  Clay 
  probably 
  continued 
  to 
  

   accumulate 
  after 
  the 
  ico 
  had 
  ceased 
  to 
  reach 
  the 
  west 
  of 
  the 
  Wold, 
  

   and 
  so 
  give 
  rise 
  to 
  the 
  Chalky 
  Clay. 
  If, 
  too, 
  the 
  Shap 
  blocks 
  are 
  

   present 
  near 
  the 
  base 
  as 
  well 
  as 
  in 
  the 
  upper 
  part 
  of 
  the 
  Purple 
  

   Clay, 
  the 
  great 
  accumulation 
  of 
  ice 
  in 
  Westmoreland 
  which 
  caused 
  

   the 
  transit 
  of 
  the 
  Pennine 
  by 
  these 
  blocks 
  must 
  have 
  preceded 
  the 
  

   rise 
  of 
  the 
  land, 
  instead 
  of 
  being 
  due 
  to 
  it, 
  as 
  suggested 
  in 
  the 
  first 
  

   part 
  of 
  this 
  memoir. 
  

  

  I 
  think 
  also, 
  on 
  consideration, 
  that 
  the 
  reason 
  why 
  none 
  of 
  the 
  

   gravel 
  of 
  the 
  great 
  submergenco 
  is 
  to 
  be 
  found 
  on 
  the 
  eastern 
  side 
  

  

  