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  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  [Feb. 
  3, 
  

  

  This 
  " 
  Crab 
  rock," 
  as 
  seen 
  in 
  the 
  section, 
  is 
  in 
  some 
  parts 
  twenty 
  

   feet 
  thick 
  ; 
  but 
  its 
  thickness 
  is 
  very 
  irregular 
  as 
  it 
  spreads 
  over 
  

   the 
  eroded 
  edges 
  of 
  the 
  Carboniferous 
  Limestone. 
  It 
  is 
  seen, 
  not 
  

   only 
  reposing 
  unconformably 
  upon 
  the 
  Carboniferous 
  rocks, 
  but 
  also 
  

   enclosing 
  veins 
  of 
  haematite 
  (see 
  fig. 
  3). 
  Another 
  locality 
  where 
  

   this 
  breccia 
  or 
  " 
  Crab 
  rock" 
  appears 
  is 
  St. 
  Helen's, 
  about 
  half 
  a 
  

   mile 
  to 
  the 
  north 
  of 
  the 
  Park 
  cutting, 
  and 
  immediately 
  east 
  from 
  

   the 
  railway. 
  Here 
  the 
  Carboniferous 
  Limestones 
  have 
  the 
  breccia 
  

   also 
  spread 
  out 
  upon 
  their 
  surfaces, 
  and 
  into 
  some 
  of 
  the 
  open 
  joints 
  

   which 
  intersect 
  the 
  underlying 
  strata 
  the 
  " 
  Crab 
  rock" 
  has 
  found 
  its 
  

   way. 
  At 
  Dalton 
  the 
  same 
  relations 
  occur. 
  Near 
  the 
  church 
  the 
  

   " 
  Crab 
  rock," 
  consisting 
  of 
  unaltered 
  fragments 
  of 
  limestone 
  cemented 
  

   together 
  by 
  a 
  red 
  matrix, 
  also 
  covers 
  over 
  the 
  Carboniferous 
  strata. 
  

   This 
  " 
  Crab 
  rock" 
  is 
  well 
  known 
  to 
  miners, 
  who 
  have 
  noticed 
  that 
  

   where 
  haematite 
  occurs 
  below 
  it, 
  in 
  the 
  Ulverstone 
  district, 
  the 
  latter 
  

   is 
  always 
  in 
  intimate 
  relation 
  to 
  the 
  former. 
  

  

  Fig. 
  3. 
  — 
  Section 
  from 
  Park 
  to 
  Furness 
  Abbey 
  (11 
  mile). 
  

  

  is 
  r 
  . 
  

  

  Park. 
  

  

  Breccia 
  

   'Crab 
  rock. 
  

  

  Furness 
  

   Abbey. 
  

  

  12 
  12 
  1 
  3 
  

  

  1. 
  Carboniferous 
  Limestone. 
  

  

  2. 
  Haematite. 
  

  

  3. 
  Fault. 
  

  

  4. 
  Corby 
  Sandstone. 
  

  

  With 
  reference 
  to 
  the 
  position 
  of 
  the 
  " 
  Crab 
  rock," 
  its 
  mineral 
  

   characters 
  lead 
  to 
  the 
  conclusion 
  that 
  it 
  is 
  of 
  like 
  age 
  with 
  the 
  lower 
  

   and 
  unaltered 
  breccias 
  of 
  Burrells, 
  west 
  of 
  Appleby 
  ; 
  for 
  it 
  possesses 
  

   none 
  of 
  the 
  magnesian 
  features 
  appertaining 
  to 
  the 
  higher 
  breccias. 
  

   Here, 
  therefore, 
  the 
  lowest 
  Permian 
  rocks 
  of 
  the 
  north-west 
  of 
  

   England 
  are 
  seen 
  ; 
  and 
  after 
  the 
  clear 
  and 
  unmistakeable 
  natural 
  

   section 
  at 
  Barrowmouth, 
  under 
  St. 
  Bees 
  Head, 
  where 
  the 
  Lower 
  

   Permian 
  is 
  reduced 
  to 
  a 
  few 
  feet 
  in 
  thickness, 
  we 
  have 
  no 
  occasion 
  

   to 
  call 
  in 
  the 
  agency 
  of 
  great 
  denudation 
  in 
  the 
  Furness 
  district. 
  

  

  In 
  truth, 
  it 
  is 
  quite 
  manifest 
  that 
  along 
  the 
  western 
  flank 
  of 
  the 
  

   old 
  slaty 
  mountains 
  of 
  Cumberland 
  we 
  meet 
  only 
  with 
  ridges 
  or 
  

   patches 
  of 
  Carboniferous 
  Limestone, 
  which, 
  with 
  the 
  exception 
  of 
  the 
  

   very 
  partial 
  breccias 
  above 
  described, 
  are 
  at 
  once 
  surrounded 
  by 
  the 
  

   middle 
  and 
  higher 
  members 
  of 
  the 
  Permian 
  group, 
  of 
  which 
  hereafter. 
  

  

  d. 
  Hcematite 
  in 
  the 
  Lower 
  Permians. 
  — 
  The 
  mode 
  in 
  which 
  that 
  

   valuable 
  ore 
  of 
  iron, 
  hcematite, 
  is 
  found 
  deposited 
  in 
  pre-existing 
  

   cavities 
  of 
  the 
  Carboniferous 
  formation, 
  and 
  sealed 
  up 
  by 
  " 
  Crab 
  

   rock," 
  is 
  a 
  matter 
  of 
  great 
  geological 
  interest. 
  Joints, 
  fissures, 
  and 
  

   caverns 
  were 
  doubtless 
  formed 
  in 
  the 
  older 
  rocks 
  antecedent 
  to 
  the 
  

   deposition 
  of 
  the 
  Permian 
  strata, 
  and 
  in 
  these 
  the 
  ores 
  of 
  iron 
  so 
  

   widely 
  diffused 
  throughout 
  the 
  Permian 
  rocks 
  have, 
  in 
  this 
  portion 
  

   of 
  the 
  north-western 
  region, 
  assumed 
  the 
  characters 
  of 
  haematite. 
  

  

  