﻿214 
  J. 
  W. 
  DAWSON 
  ON 
  THE 
  UPPER 
  COAL-EOKMATION 
  OF 
  

  

  coarse 
  and 
  pebbly, 
  and 
  occasionally 
  in 
  thick 
  massive 
  beds. 
  Several 
  

   of 
  the 
  beds 
  of 
  shale 
  contain 
  concretions 
  of 
  limestone, 
  in 
  one 
  case 
  

   forming 
  a 
  nearly 
  continuous 
  bed, 
  and 
  with 
  no 
  fossils 
  except 
  a 
  few 
  

   casts 
  of 
  a 
  Gythere. 
  In 
  one 
  of 
  the 
  lower 
  beds 
  of 
  sandstone 
  seen 
  on 
  

   Carribou 
  River 
  there 
  are 
  concretions 
  of 
  grey 
  copper, 
  and 
  fossil 
  trunks 
  

   of 
  trees 
  penetrated 
  by 
  this 
  mineral 
  ; 
  and 
  some 
  of 
  the 
  fossil 
  trees 
  

   found 
  in 
  the 
  sandstones 
  on 
  the 
  coast 
  are 
  partly 
  mineralized 
  with 
  

   sulphate 
  of 
  baryta. 
  

  

  The 
  only 
  material 
  difference 
  in 
  mineral 
  character 
  is 
  that 
  red 
  beds 
  

   become 
  more 
  prevalent 
  toward 
  the 
  upper 
  part 
  of 
  the 
  section, 
  where 
  

   the 
  general 
  character 
  of 
  the 
  beds 
  is 
  precisely 
  that 
  of 
  the 
  supposed 
  

   Upper 
  Coal-formation 
  rocks 
  at 
  Miminigash, 
  Governor's 
  Island, 
  and 
  

   Gallas 
  Point 
  in 
  Prince-Edward 
  Island, 
  and 
  on 
  the 
  coast 
  of 
  New 
  

   Brunswick 
  at 
  Cape 
  Jourimain*. 
  

  

  The 
  following 
  statements, 
  reduced 
  from 
  my 
  sectional 
  lists, 
  will 
  

   serve 
  to 
  illustrate 
  these 
  points 
  of 
  mineral 
  character. 
  

  

  In 
  the 
  whole 
  section 
  the 
  sandstones, 
  including 
  the 
  argillaceous 
  

   sandstones, 
  are 
  to 
  the 
  shales 
  in 
  the 
  proportion 
  of 
  about 
  two 
  to 
  one 
  

   in 
  vertical 
  thickness, 
  and 
  the 
  grey 
  and 
  buff 
  sandstones 
  are 
  about 
  

   equal 
  to 
  those 
  which 
  are 
  brown 
  and 
  red, 
  while 
  the 
  red 
  and 
  mottled 
  

   shales 
  greatly 
  preponderate 
  over 
  those 
  which 
  are 
  grey. 
  

  

  In 
  the 
  lower 
  half 
  of 
  the 
  section, 
  extending 
  to 
  the 
  mouth 
  of 
  Toney 
  

   River, 
  the 
  grey 
  sandstone, 
  red 
  sandstone, 
  and 
  shales 
  (mostly 
  red) 
  are 
  

   in 
  the 
  proportions 
  of 
  4|, 
  3, 
  6|. 
  In 
  the 
  upper 
  half 
  of 
  the 
  section 
  they 
  

   are 
  in 
  the 
  proportions 
  of 
  4^, 
  5|, 
  3 
  ; 
  so 
  that 
  red 
  sandstones 
  become 
  

   decidedly 
  more 
  prevalent 
  in 
  the 
  upper 
  part, 
  where 
  there 
  is 
  also 
  a 
  

   greater 
  proportion 
  of 
  coarse 
  pebbly 
  sandstones 
  and 
  of 
  light-red 
  shale 
  

   with 
  greenish 
  stains. 
  

  

  If 
  we 
  compare 
  this 
  with 
  the 
  upper 
  part 
  of 
  the 
  Joggins 
  section 
  as 
  

   given 
  in 
  Sir 
  William 
  Logan's 
  lists, 
  we 
  find 
  a 
  thickness 
  of 
  2267 
  feet 
  ; 
  

   and 
  if 
  we 
  regard 
  the 
  Ragged-Reef 
  Sandstones 
  as 
  equivalent 
  to 
  the 
  

   heavy 
  sandstones 
  at 
  the 
  base 
  of 
  the 
  Pictou 
  section, 
  it 
  is 
  possible 
  

   that 
  the 
  upper 
  part 
  of 
  the 
  latter 
  is 
  not 
  represented 
  at 
  the 
  Joggins. 
  

   Taking 
  the 
  proportions 
  of 
  sandstones 
  and 
  shales 
  at 
  the 
  latter 
  place, 
  

   we 
  find 
  them 
  to 
  be 
  grey 
  sandstone 
  12, 
  red 
  and 
  brown 
  sandstone 
  1, 
  

   shale 
  10 
  ; 
  so 
  that 
  here 
  the 
  proportions 
  of 
  sandstones 
  to 
  shales 
  are 
  

   not 
  very 
  dissimilar 
  to 
  those 
  in 
  the 
  lower 
  part 
  of 
  the 
  Pictou 
  series, 
  

   but 
  the 
  grey 
  sandstones 
  are 
  greatly 
  more 
  prevalent. 
  Like 
  those 
  in 
  

   the 
  upper 
  part 
  at 
  Pictou, 
  some 
  of 
  the 
  upper 
  beds 
  at 
  the 
  Joggins 
  are 
  

   coarse 
  and 
  pebbly, 
  a 
  character 
  not 
  observed, 
  in 
  either 
  Coal-field, 
  in 
  

   the 
  sandstones 
  of 
  the 
  Middle 
  Coal-formation. 
  

  

  If, 
  on 
  the 
  other 
  hand, 
  we 
  turn 
  to 
  Prince-Edward 
  Island, 
  the 
  

   geological 
  relations, 
  and 
  especially 
  the 
  fact 
  that 
  the 
  outcrops 
  on 
  

   Prince-Edward 
  Island 
  correspond 
  with 
  the 
  extension 
  of 
  two 
  of 
  the 
  

   New-Brunswick 
  Carboniferous 
  anticlinals, 
  Avould 
  lead 
  us 
  to 
  believe 
  

   that 
  the 
  upper 
  Coal-formation 
  beds 
  seen, 
  at 
  Gallas 
  Point, 
  and 
  

   amounting 
  to 
  about 
  800 
  feet 
  in 
  vertical 
  thickness, 
  must 
  belong 
  to 
  

   the 
  upper 
  part 
  of 
  the 
  Pictou 
  series, 
  or 
  may 
  even 
  reach 
  some 
  way 
  

   above 
  its 
  summit. 
  Accordingly 
  we 
  find 
  the 
  proportions 
  of 
  the 
  

   * 
  Report 
  on 
  Prince-Edward 
  Island. 
  

  

  