﻿226 
  T. 
  M. 
  KEADE 
  ON 
  THE 
  CHALK-MASSES 
  

  

  above 
  the 
  shore, 
  were 
  found 
  a 
  series 
  of 
  false-bedded 
  gravels 
  and 
  

   sands, 
  then 
  laminated 
  sand 
  and 
  clay 
  capped 
  by 
  a 
  dark 
  loamy 
  bed, 
  

   together 
  like 
  those 
  I 
  have 
  described 
  as 
  occurring 
  above 
  the 
  " 
  iron 
  

   pan" 
  at 
  Weybourne. 
  

  

  Nearly 
  opposite, 
  a 
  ferruginous 
  pan 
  was 
  exposed 
  on 
  the 
  shore 
  ; 
  and 
  

   still 
  further 
  to 
  the 
  north-west 
  the 
  cliffs 
  clearly 
  displayed 
  15 
  feet 
  of 
  false- 
  

   bedded 
  sands. 
  It 
  is 
  not 
  my 
  wish 
  to 
  interfere 
  in 
  the 
  controversies 
  

   that 
  have 
  been 
  raging 
  of 
  late 
  among 
  geologists 
  in 
  the 
  neighbour- 
  

   hood 
  of 
  Norwich 
  regarding 
  these 
  preglacial 
  beds 
  or 
  "Porest-bed 
  

   series 
  ; 
  " 
  but 
  for 
  the 
  purposes 
  of 
  this 
  paper 
  I 
  must 
  state 
  my 
  convic- 
  

   tion 
  that 
  the 
  true 
  Drift-beds 
  appear 
  to 
  rest 
  on 
  a 
  pretty 
  well-marked 
  

   eroded 
  surface 
  of 
  the 
  preglacial 
  beds 
  usually 
  known 
  as 
  the 
  Forest- 
  

   bed 
  series 
  ; 
  and 
  I 
  see 
  no 
  reason 
  to 
  doubt 
  that 
  Mr. 
  J. 
  H. 
  Blake 
  * 
  has 
  

   at 
  points, 
  where 
  eroded, 
  discovered 
  the 
  remains 
  of 
  a 
  true 
  land- 
  

   surface 
  similar 
  and 
  equivalent 
  to 
  the 
  "rootlet-bed" 
  which, 
  in 
  

   his 
  company, 
  I 
  saw 
  remarkably 
  well 
  exposed 
  at 
  the 
  base 
  of 
  the 
  

   Kessingland 
  cliffs. 
  It 
  is 
  held 
  by 
  some 
  that 
  this 
  " 
  rootlet-bed 
  " 
  

   does 
  not 
  contain 
  the 
  roots 
  of 
  forest 
  trees 
  ; 
  but 
  for 
  our 
  purpose 
  this 
  

   is 
  a 
  matter 
  of 
  no 
  moment, 
  as 
  even 
  if 
  they 
  were 
  roots 
  of 
  ferns, 
  which 
  

   I 
  doubt, 
  it 
  will 
  be 
  equally 
  a 
  land-surface 
  and 
  serve 
  just 
  as 
  well 
  for 
  a 
  

   base-line 
  for 
  our 
  drift-deposits. 
  That 
  it 
  was 
  a 
  land-surface, 
  after 
  

   the 
  diligent 
  investigation 
  I 
  have 
  carried 
  on 
  for 
  years 
  on 
  a 
  parallel 
  

   subject 
  in 
  my 
  own 
  neighbourhood, 
  I 
  have 
  very 
  little 
  doubt; 
  but 
  it 
  is 
  

   quite 
  possible 
  that 
  the 
  upper 
  part 
  of 
  the 
  bed 
  has 
  been 
  eroded, 
  and 
  

   that 
  the 
  rootlets 
  we 
  see 
  are 
  the 
  tap-roots, 
  as 
  they 
  are 
  all 
  vertical 
  f. 
  

  

  I 
  could 
  parallel 
  the 
  rootlets 
  pretty 
  closely 
  in 
  certain 
  stages 
  of 
  the 
  

   denudation 
  of 
  the 
  postglacial 
  submarine 
  forest-bed 
  at 
  the 
  Alt 
  

   mouth, 
  Lancashire*. 
  

  

  From 
  the 
  foregoing 
  considerations 
  it 
  will 
  be 
  seen 
  that 
  I 
  consider 
  

   the 
  lower 
  part 
  of 
  the 
  Cromer 
  Till 
  to 
  represent 
  the 
  incoming 
  of 
  the 
  

   true 
  glacial 
  conditions. 
  Mr. 
  Searles 
  V. 
  Wood 
  puts 
  the 
  Crag 
  at 
  

   "Weybourne 
  with 
  the 
  glacial 
  series, 
  because 
  it 
  contains 
  the 
  shell 
  

  

  * 
  Presidential 
  address 
  to 
  the 
  Norwich 
  Geol. 
  Soc, 
  Session 
  1879-80, 
  p. 
  146, 
  by 
  

   J. 
  H. 
  Blake, 
  F.G.S. 
  

  

  t 
  April 
  28, 
  1882. 
  — 
  This 
  bed 
  is 
  described 
  in 
  a 
  letter 
  of 
  Sir 
  Charles 
  Lyell 
  to 
  

   Sir 
  Charles 
  Bunbury 
  in 
  1869. 
  He 
  says, 
  "But 
  I 
  wished 
  much 
  I 
  could 
  have 
  had 
  

   the 
  advantage 
  of 
  walking 
  with 
  you 
  along 
  the 
  Kessingland 
  and 
  Pakefield 
  Cliff, 
  

   about 
  50 
  and 
  60 
  feet 
  high, 
  where, 
  at 
  the 
  base 
  for 
  more 
  than 
  a 
  mile, 
  in 
  a 
  

   bed 
  of 
  what 
  I 
  formerly 
  called 
  green 
  till, 
  a 
  homogeneous 
  unstratified 
  clay, 
  I 
  

   found 
  upright 
  plants 
  or 
  shrubs 
  standing 
  vertical, 
  with 
  their 
  roots 
  in 
  the 
  same 
  

   green 
  soil 
  (apparently 
  tap-roots), 
  also 
  vertical 
  and 
  a 
  foot 
  or 
  more 
  long. 
  In 
  

   one 
  place, 
  near 
  Pakefield, 
  this 
  lower 
  stratum 
  was 
  laminated, 
  and 
  contained 
  

   prostrate 
  flattened 
  trees 
  a 
  foot 
  or 
  more 
  in 
  diameter. 
  Over 
  this 
  green 
  till, 
  with 
  

   plants 
  in 
  situ 
  (of 
  which 
  I 
  have 
  kept 
  a 
  few 
  specimens 
  to 
  show 
  you), 
  reposes 
  

   stratified 
  sand 
  many 
  yards 
  thick, 
  and 
  over 
  this 
  drift, 
  with 
  plicated 
  boulders 
  of 
  

   Chalk, 
  Lias 
  with 
  fossils 
  (Avicula 
  cygnipes), 
  numerous 
  Ammonites, 
  Belemnites, 
  

   pieces 
  of 
  mica-schist, 
  sandstone, 
  greenstone, 
  and 
  other 
  rocks. 
  It 
  is 
  strange 
  to 
  

   see 
  this 
  glacial 
  drift 
  covering 
  the 
  bed 
  for 
  a 
  mile 
  and 
  a 
  half, 
  with 
  trees 
  which 
  

   must 
  have 
  grown 
  in 
  situ, 
  and 
  must 
  have 
  sunk 
  down 
  so 
  as 
  to 
  allow 
  first 
  the 
  sand 
  

   and 
  then 
  the 
  boulder-clay 
  to 
  accumulate 
  over 
  it." 
  — 
  Life 
  of 
  Sir 
  Charles 
  Lyell, 
  

   vol. 
  ii. 
  p. 
  439. 
  

  

  \ 
  Described 
  in 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  1878, 
  pp. 
  447, 
  448, 
  and 
  in 
  various 
  

   papers 
  in 
  the 
  Proceedings 
  of 
  the 
  Liverpool 
  Geological 
  Society. 
  

  

  