﻿Schachert 
  — 
  The 
  Taconic 
  System 
  Resurrected. 
  113 
  

  

  Art. 
  VII. 
  — 
  The 
  Taconic 
  System 
  Resurrected; 
  by 
  

   Charles 
  Schxjchert. 
  

  

  In 
  the 
  Centennial 
  number 
  of 
  this 
  Journal, 
  July, 
  1918, 
  

   the 
  writer 
  made 
  the 
  following 
  statements 
  : 
  

  

  "The 
  Taconic 
  system 
  was 
  first 
  announced 
  by 
  Ebenezer 
  Emmons 
  

   in 
  1841, 
  and 
  clearly 
  defined 
  in 
  1842 
  " 
  (p. 
  75 
  ) 
  . 
  . 
  . 
  . 
  "It 
  appears 
  

   that 
  everywhere 
  in 
  America 
  the 
  Lower 
  Cambrian 
  formations 
  are 
  

   separated 
  by 
  a 
  land 
  interval 
  of 
  long 
  duration 
  from 
  those 
  of 
  

   Middle 
  Cambrian 
  time. 
  These 
  formations 
  therefore 
  unite 
  into 
  

   a 
  natural 
  system 
  of 
  rocks 
  or 
  a 
  period 
  of 
  time. 
  Between 
  Middle 
  

   and 
  Upper 
  Cambrian 
  time, 
  however, 
  there 
  appears 
  to 
  be 
  a 
  com- 
  

   plete 
  transition 
  in 
  the 
  Cordilleran 
  trough, 
  binding 
  these 
  two 
  

   series 
  of 
  deposits 
  into 
  one 
  natural 
  or 
  diastrophic 
  system. 
  The 
  

   Middle 
  and 
  Upper 
  Cambrian 
  series 
  can 
  be 
  continued 
  for 
  the 
  

   present 
  under 
  the 
  term 
  Cambrian 
  system, 
  a 
  term, 
  however, 
  that 
  

   is 
  by 
  no 
  means 
  in 
  good 
  standing 
  for 
  these 
  formations" 
  (pp. 
  

   77-78). 
  

  

  What 
  the 
  writer 
  now 
  wishes 
  to 
  set 
  forth 
  can 
  not 
  be 
  

   clearly 
  understood 
  without 
  further 
  statements 
  that 
  he 
  

   made 
  at 
  the 
  same 
  time 
  in 
  connection 
  with 
  the 
  Silurian 
  

   controversy. 
  These 
  are: 
  

  

  1 
  ' 
  Just 
  as 
  in 
  America 
  the 
  base 
  of 
  the 
  Paleozoic 
  was 
  involved 
  in 
  

   a 
  protracted 
  controversy, 
  so 
  in 
  England 
  the 
  Cambrian- 
  Silurian 
  

   succession 
  was 
  a 
  subject 
  of 
  long 
  debate 
  between 
  Sedgwick 
  and 
  

   Murchison, 
  and 
  among 
  the 
  succeeding 
  geologists 
  of 
  Europe. 
  The 
  

   history 
  of 
  the 
  solution 
  is 
  clearly 
  and 
  justly 
  stated 
  in 
  the 
  Journal 
  

   by 
  James 
  D. 
  Dana 
  under 
  the 
  title 
  'Sedgwick 
  and 
  Murchison: 
  

   Cambrian 
  and 
  Silurian' 
  (39, 
  167, 
  1890), 
  and 
  by 
  Sir 
  Archibald 
  

   Geikie 
  in 
  his 
  Text-book 
  of 
  Geology, 
  1903" 
  (p. 
  78). 
  . 
  . 
  . 
  

  

  "We 
  have 
  arrived 
  at 
  a 
  time 
  when 
  our 
  knowledge 
  of 
  the 
  strati- 
  

   graphic 
  and 
  faunal 
  sequence, 
  plus 
  the 
  orogenic 
  record 
  as 
  recog- 
  

   nized 
  in 
  the 
  principle 
  of 
  diastrophism, 
  should 
  be 
  reflected 
  in 
  the 
  

   terminology 
  of 
  the 
  geologic 
  time-table. 
  It 
  would 
  be 
  easy 
  to 
  offer 
  

   a 
  satisfactory 
  nomenclature 
  if 
  we 
  were 
  not 
  bound 
  by 
  the 
  law 
  of 
  

   priority 
  in 
  publication, 
  and 
  if 
  no 
  one 
  had 
  the 
  geologic 
  chronology 
  

   of 
  his 
  own 
  time 
  ingrained 
  in 
  his 
  memory. 
  In 
  addition, 
  the 
  end- 
  

   less 
  literature, 
  with 
  its 
  accepted 
  nomenclature, 
  bars 
  our 
  way. 
  

   Therefore, 
  with 
  a 
  view 
  of 
  creating 
  the 
  least 
  change 
  in 
  geologic 
  

   nomenclature, 
  and 
  of 
  doing 
  the 
  greatest 
  justice 
  to 
  our 
  predeces- 
  

   sors 
  that 
  the 
  present 
  conditions 
  of 
  our 
  knowledge 
  will 
  allow, 
  the 
  

   following 
  scheme 
  is 
  offered: 
  

  

  "Silurian 
  period. 
  Llandovery 
  to 
  top 
  of 
  Ludlow 
  in 
  Europe. 
  

   Alexandrian- 
  Cataract-Medina 
  to 
  top 
  of 
  Manlius 
  in 
  America. 
  

  

  "Champlain 
  (1842) 
  or 
  Ordovician 
  (1879) 
  period. 
  Arenig 
  to 
  

  

  