﻿160 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  [Feb. 
  3, 
  

  

  grey 
  laminated 
  false-bedded 
  sandstones, 
  the 
  lower 
  portion 
  of 
  which 
  

   forms 
  a 
  cliff, 
  well 
  seen 
  near 
  Cargs. 
  The 
  same 
  light- 
  coloured 
  sand- 
  

   stones 
  form 
  the 
  bed 
  of 
  the 
  river 
  to 
  near 
  Kirkandrews. 
  A 
  short 
  

   distance 
  below 
  Kirkandrews 
  purple 
  and 
  grey 
  shales 
  are 
  again 
  seen 
  

   in 
  the 
  west 
  bank 
  of 
  the 
  river, 
  their 
  position 
  being 
  nearly 
  horizontal 
  ; 
  

   beyond 
  which, 
  at 
  Beaumont, 
  the 
  same 
  strata 
  dip 
  south 
  at 
  35°, 
  and 
  

   the 
  surfaces 
  of 
  the 
  shales 
  here 
  are 
  frequently 
  marked 
  by 
  pseudo- 
  

   morphs 
  of 
  bay-salt. 
  No 
  further 
  traces 
  of 
  these 
  rocks 
  are 
  seen 
  in 
  

   the 
  Eden, 
  nor 
  do 
  they 
  occur 
  in 
  the 
  district. 
  At 
  Rockcliff 
  red 
  sand- 
  

   stones 
  of 
  the 
  Permian 
  formation 
  make 
  their 
  appearance. 
  

  

  The 
  nature 
  and 
  arrangement 
  of 
  the 
  strata 
  seen 
  in 
  the 
  sections 
  of 
  

   the 
  Eden 
  near 
  Carlisle, 
  and 
  west 
  of 
  that 
  place, 
  are 
  altogether 
  different 
  

   from 
  those 
  of 
  the 
  Permian 
  rocks 
  of 
  the 
  north-west 
  of 
  England. 
  The 
  

   highest 
  beds 
  here 
  consist 
  of 
  purple 
  shales 
  with 
  grey 
  bands, 
  especially 
  

   in 
  their 
  lower 
  portions. 
  These 
  purple 
  shales 
  greatly 
  resemble 
  those 
  of 
  

   the 
  Keuper 
  series, 
  the 
  grey 
  beds 
  upon 
  which 
  they 
  rest 
  having 
  con- 
  

   siderable 
  affinity 
  to 
  the 
  water-stones 
  ; 
  and 
  the 
  light- 
  coloured 
  sand- 
  

   stones 
  are 
  probably 
  the 
  highest 
  members 
  of 
  the 
  Bunter. 
  That 
  these 
  

   rocks 
  appertain 
  to 
  the 
  portion 
  of 
  the 
  Trias 
  assigned 
  to 
  them 
  is 
  still 
  

   further 
  corroborated 
  by 
  the 
  fact 
  that 
  Liassic 
  strata 
  occur 
  within 
  a 
  

   short 
  distance 
  southwards, 
  as 
  shown 
  by 
  Mr. 
  Binney*. 
  

  

  The 
  occurrence 
  of 
  Triassic 
  and 
  Liassic 
  strata 
  in 
  this 
  part 
  of 
  Cum- 
  

   berland 
  results 
  probably 
  from 
  faults 
  throwing 
  down 
  these 
  and 
  the 
  

   underlying 
  formations. 
  In 
  no 
  portion 
  of 
  Cumberland, 
  however, 
  have 
  

   we 
  any 
  evidence 
  of 
  the 
  mode 
  in 
  which 
  the 
  lower 
  members 
  of 
  the 
  

   Mesozoic 
  group 
  are 
  associated 
  with 
  the 
  upper 
  portion 
  of 
  the 
  Palaeo- 
  

   zoic 
  division. 
  

  

  § 
  6. 
  Dolomitization. 
  * 
  

  

  Reference 
  has 
  already 
  been 
  made 
  to 
  the 
  unaltered 
  character 
  of 
  

   the 
  lower 
  sandstones. 
  Their 
  nature 
  shows 
  that 
  the 
  dolomitizing 
  

   influence 
  had 
  not 
  begun 
  to 
  act 
  when 
  they 
  were 
  being 
  deposited. 
  

   The 
  period 
  when 
  this 
  agency 
  commenced, 
  and 
  that 
  when 
  it 
  ceased, 
  

   can, 
  so 
  far 
  as 
  the 
  Permian 
  rocks 
  of 
  the 
  north-west 
  of 
  England 
  are 
  

   concerned, 
  be 
  very 
  nearly 
  determined. 
  Dr. 
  Blyth, 
  of 
  Queen's 
  Col- 
  

   lege, 
  Cork, 
  has 
  kindly 
  furnished 
  us 
  with 
  the 
  results 
  of 
  his 
  analyses 
  

   of 
  different 
  rocks 
  from 
  various 
  portions 
  of 
  the 
  Permian 
  formation 
  of 
  

   Cumberland 
  and 
  Westmoreland. 
  

  

  As 
  regards 
  the 
  red 
  sandstones 
  of 
  the 
  Penrith 
  series, 
  a 
  specimen 
  

   of 
  these 
  from 
  the 
  Beacon 
  quarry, 
  about 
  a 
  mile 
  east 
  of 
  Penrith, 
  

   consisted 
  almost 
  exclusively 
  of 
  quartz-granules 
  ; 
  the 
  cementing 
  ma- 
  

   trix 
  of 
  these 
  granules 
  being 
  silicates 
  of 
  lime, 
  iron, 
  and 
  magnesia, 
  

   the 
  two 
  former 
  being 
  in 
  greater 
  proportions 
  than 
  the 
  latter. 
  The 
  red 
  

   colour 
  of 
  this 
  sandstone 
  is 
  owing 
  to 
  a 
  considerable 
  amount 
  of 
  oxide 
  of 
  

   iron 
  incrusting 
  the 
  silica-granules, 
  which 
  can 
  be 
  dissolved 
  off, 
  leaving 
  

   the 
  granules 
  quite 
  white. 
  The 
  white 
  sandstones, 
  occasionally 
  asso- 
  

   ciated 
  with 
  the 
  lower 
  sandstones 
  in 
  the 
  same 
  locality, 
  consist 
  also 
  of 
  

   quartz-granules 
  cemented 
  together 
  by 
  the 
  same 
  substances 
  ; 
  but 
  here 
  

   the 
  silicates 
  of 
  lime 
  and 
  magnesia 
  are 
  in 
  excess, 
  while 
  the 
  silicate 
  of 
  

  

  * 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  toI. 
  xv. 
  p. 
  549. 
  

  

  