﻿52 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  upon 
  the 
  formation 
  of 
  the 
  ore 
  beds, 
  have 
  been 
  well 
  stated 
  by 
  

   Professor 
  Smyth 
  in 
  a 
  paragraph 
  of 
  his 
  paper 
  of 
  which 
  the 
  fol- 
  

   lowing 
  is 
  a 
  translation. 
  

  

  By 
  reference 
  to 
  a 
  geological 
  map 
  of 
  the 
  eastern 
  United 
  States, 
  

   it 
  will 
  be 
  observed 
  that 
  the 
  Clinton 
  beds 
  were 
  deposited 
  in 
  a 
  

   sea 
  which 
  received 
  the 
  drainage 
  from 
  an 
  extensive 
  area 
  of 
  crys- 
  

   talline 
  rocks. 
  Long 
  continued 
  denundation 
  of 
  these 
  rocks, 
  which 
  

   are 
  made 
  up 
  in 
  part 
  of 
  iron-bearing 
  silicates 
  and 
  inclose 
  import- 
  

   ant 
  bodies 
  of 
  magnetite 
  and 
  pyrite, 
  set 
  free 
  large 
  amounts 
  of 
  

   iron 
  to 
  be 
  carried 
  seaward 
  in 
  solution 
  or 
  suspension. 
  Along 
  the 
  

   coast 
  of 
  the 
  sea 
  there 
  were 
  in 
  Clinton 
  time 
  extensive 
  swamps 
  

   and 
  mud 
  flats, 
  evidenced 
  by 
  the 
  frequent 
  surface 
  markings, 
  

   cracks 
  and 
  tracks 
  of 
  crustaceans 
  and 
  worms 
  found 
  in 
  the 
  

   shales 
  and 
  sandstones. 
  In 
  other 
  places 
  calcareous 
  fossil 
  frag- 
  

   ments 
  accumulated 
  and 
  were 
  rolled 
  about 
  and 
  ground 
  by 
  the 
  

   waves 
  and 
  finally 
  deposited 
  in 
  shallow 
  water 
  forming 
  shell 
  

   beaches 
  similar 
  to 
  those 
  of 
  the 
  present 
  day, 
  for 
  example, 
  the 
  

   coquina 
  on 
  the 
  Florida 
  coast. 
  Most 
  of 
  the 
  iron 
  brought 
  down 
  

   by 
  land 
  drainage 
  of 
  course 
  would 
  be 
  wasted, 
  but 
  a 
  part 
  would 
  

   be 
  precipitated 
  to 
  form 
  the 
  ore 
  beds. 
  The 
  precipitation 
  occurred 
  

   in 
  two 
  ways, 
  thereby 
  giving 
  rise 
  to 
  two 
  ore 
  varieties. 
  Where 
  

   the 
  waters 
  were 
  collected 
  in 
  partially 
  or 
  completely 
  inclosed 
  

   basins, 
  the 
  iron 
  was 
  thrown 
  down 
  by 
  slow 
  oxidation 
  and 
  gath- 
  

   ered 
  in 
  layer 
  upon 
  layer 
  about 
  the 
  sand 
  grains, 
  thus 
  forming 
  the 
  

   oolitic 
  ore. 
  The 
  conditions 
  requisite 
  to 
  this 
  method 
  of 
  precipi- 
  

   tation 
  obtained 
  apparently 
  over 
  no 
  great 
  areas, 
  so 
  that 
  the 
  oolitic 
  

   beds 
  are 
  generally 
  of 
  limited 
  extent. 
  Again 
  the 
  ferruginous 
  

   waters 
  came 
  in 
  contact 
  with 
  the 
  calcareous 
  shell 
  fragments; 
  

   here 
  the 
  iron 
  was 
  precipitated 
  partly 
  by 
  reaction 
  with 
  the 
  lime 
  

   carbonate, 
  yet 
  mostly 
  by 
  oxidation, 
  while 
  the 
  lime 
  was 
  carried 
  

   off 
  in 
  solution 
  by 
  the 
  aid 
  of 
  the 
  carbon 
  dioxid 
  set 
  free. 
  As 
  this 
  

   process 
  took 
  place 
  while 
  the 
  shells 
  were 
  being 
  rolled 
  about 
  or 
  

   heaped 
  up 
  in 
  loose 
  aggregates 
  and 
  was 
  chiefly 
  a 
  result 
  of 
  oxida- 
  

   tion, 
  the 
  iron 
  took 
  the 
  form 
  of 
  oxid 
  rather 
  than 
  carbonate. 
  It 
  

   need 
  scarcely 
  be 
  stated 
  that 
  this 
  method 
  of 
  replacement 
  is 
  

   widely 
  different 
  from 
  the 
  other 
  process 
  of 
  replacement 
  that 
  has 
  been 
  

   applied 
  to 
  the 
  ores. 
  The 
  progress 
  of 
  the 
  reaction 
  advanced 
  step 
  

   by 
  step 
  with 
  the 
  accumulation 
  of 
  the 
  fossil 
  fragments. 
  Thus, 
  

   while 
  the 
  iron 
  is 
  a 
  secondary 
  product 
  as 
  regards 
  the 
  individual 
  

   particles 
  of 
  ore, 
  it 
  is 
  primary 
  in 
  relation 
  to 
  the 
  ore 
  bed 
  itself. 
  

   After 
  the 
  ores 
  had 
  thus 
  been 
  collected 
  into 
  loosely 
  aggregated 
  

   masses 
  of 
  grains 
  and 
  altered 
  fossils, 
  they 
  were 
  compacted 
  into 
  

   beds 
  and 
  covered 
  by 
  shales, 
  sandstones 
  and 
  limestones. 
  As 
  a 
  

   result, 
  the 
  grains 
  and 
  fragments 
  rich 
  in 
  iron 
  are 
  frequently 
  sur- 
  

   rounded 
  by 
  pure 
  calcite, 
  a 
  circumstance 
  that 
  is 
  far 
  from 
  being 
  

   opposed 
  to 
  the 
  present 
  theory 
  of 
  ore 
  formation, 
  but 
  rather 
  in 
  line 
  

   with 
  what 
  one 
  would 
  expect. 
  

  

  