﻿J. 
  J. 
  Stevenson 
  — 
  Origin 
  of 
  Formkohle. 
  219 
  

  

  required 
  for 
  conversion 
  of 
  peat 
  into 
  hard 
  coal 
  may 
  still 
  be 
  open 
  

   to 
  debate 
  ; 
  but 
  in 
  this 
  case 
  the 
  speed 
  of 
  conversion 
  exceeded 
  

   that 
  conceived 
  by 
  the 
  most 
  earnest 
  advocate, 
  since 
  the 
  change 
  

   must 
  have 
  been 
  complete 
  before 
  the 
  bog 
  ceased 
  to 
  grow. 
  

  

  But 
  the 
  author 
  of 
  this 
  hypothesis 
  is 
  not 
  wedded 
  too 
  firmly 
  

   to 
  a 
  belief 
  that 
  the 
  coal 
  was 
  already 
  hard. 
  On 
  page 
  142 
  of 
  his 
  

   work, 
  one 
  finds 
  two 
  paragraphs 
  which 
  seem 
  to 
  represent 
  an 
  

   after- 
  thought. 
  It 
  would 
  appear 
  that 
  bursting 
  peat 
  bogs 
  might 
  

   give 
  material 
  for 
  a 
  layer 
  of 
  coal 
  ; 
  the 
  great 
  bog 
  of 
  Kampar 
  

   river 
  in 
  Sumatra, 
  described 
  by 
  Koorders, 
  is 
  pulpy, 
  so 
  that 
  its 
  

   material 
  could 
  be 
  removed 
  by 
  high 
  water 
  and 
  be 
  deposited 
  

   elsewhere. 
  But 
  the 
  difficulties 
  are 
  no 
  less 
  along 
  this 
  path. 
  

  

  The 
  basins, 
  in 
  which 
  Formkohle 
  occurs, 
  are 
  small 
  and 
  many 
  

   of 
  them 
  seem 
  to 
  have 
  been 
  isolated 
  throughout 
  their 
  existence 
  

   as 
  coal 
  basins. 
  Their 
  distribution 
  suggests 
  conditions 
  such 
  as 
  

   exist 
  in 
  some 
  of 
  our 
  northern 
  states, 
  where 
  one 
  finds 
  swamps, 
  

   large 
  and 
  small, 
  scattered 
  over 
  the 
  several 
  areas. 
  As 
  these 
  

   basins 
  of 
  Sachsen 
  cannot 
  be 
  brought 
  into 
  relation 
  with 
  any 
  

   general 
  system 
  of 
  Oligocene 
  drainage, 
  it 
  would 
  seem 
  that 
  one 
  

   who 
  asserts 
  the 
  doctrine 
  of 
  transport 
  must 
  seek 
  the 
  source 
  of 
  

   the 
  material 
  as 
  well 
  as 
  an 
  explanation 
  of 
  the 
  phenomena 
  within 
  

   the 
  area 
  of 
  local 
  drainage 
  — 
  which, 
  in 
  some 
  cases, 
  was 
  much 
  

   less 
  than 
  30 
  or 
  40 
  square 
  miles, 
  including 
  the 
  space 
  now 
  occu- 
  

   pied 
  by 
  the 
  coal 
  itself. 
  It 
  is 
  possible 
  that 
  enough 
  vegetable 
  

   matter 
  might 
  accumulate 
  on 
  the 
  low 
  hills 
  surrounding 
  the 
  

   present 
  coal 
  area 
  ; 
  enough 
  to 
  give, 
  for 
  example, 
  the 
  lower 
  or 
  

   Formkohle 
  division 
  of 
  the 
  bed 
  at 
  Orebkau, 
  described 
  by 
  Kuss- 
  

   wurm. 
  There 
  would 
  still 
  remain 
  the 
  difficulty 
  of 
  accounting 
  

   for 
  the 
  uprooting 
  and 
  transferring 
  of 
  the 
  more 
  or 
  less 
  forested 
  

   bog 
  to 
  the 
  lower 
  forested 
  part 
  of 
  the 
  basin. 
  The 
  extreme 
  

   toughness 
  of 
  recent 
  peat 
  and 
  its 
  strenuous 
  resistance 
  to 
  eroding 
  

   agents 
  are 
  among 
  the 
  most 
  familiar 
  facts 
  — 
  and 
  one 
  must 
  empha- 
  

   size 
  anew 
  that 
  only 
  bog 
  material 
  can 
  be 
  considered 
  in 
  this 
  con- 
  

   nection, 
  as 
  there 
  are 
  no 
  Eocene 
  coals 
  in 
  the 
  districts 
  under 
  con- 
  

   sideration. 
  To 
  remove 
  the 
  mass 
  of 
  peat 
  there 
  would 
  be 
  

   required 
  a 
  series 
  of 
  cataclysmic 
  cloudbursts, 
  possessed 
  of 
  more 
  

   than 
  ordinary 
  discrimination, 
  so 
  as 
  to 
  end 
  their 
  destructive 
  

   work 
  with 
  removal 
  of 
  the 
  peat 
  and 
  to 
  carry 
  out 
  none 
  of 
  the 
  

   underlying 
  inorganic 
  matter. 
  

  

  The 
  importance 
  assigned 
  to 
  shrinkage 
  cracks 
  seems 
  to 
  be 
  

   excessive, 
  for 
  it 
  is 
  not 
  clear 
  that 
  the 
  crevices 
  are 
  actually 
  

   shrinkage 
  cracks. 
  If 
  the 
  transported 
  material 
  were 
  coal 
  and 
  

   deposited 
  under 
  even 
  the 
  slight 
  cover 
  of 
  water 
  imagined 
  by 
  

   the 
  author, 
  drying 
  cracks 
  would 
  be 
  insignificant. 
  If 
  the 
  

   material 
  were 
  still 
  peat 
  and 
  there 
  were 
  a 
  similar 
  thin 
  cover 
  of 
  

   water, 
  the 
  probabilities 
  are 
  almost 
  certainties 
  that 
  the 
  peat 
  

   would 
  become 
  a 
  living 
  bog. 
  In 
  any 
  case, 
  there 
  is 
  no 
  reason 
  

  

  