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  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  great 
  valley 
  shows 
  all 
  the 
  strata 
  from 
  the 
  Pamelia 
  to 
  the 
  Oswego 
  

   sandstone. 
  The 
  east 
  wall 
  of 
  Precambric 
  rocks 
  is 
  deeply 
  buried 
  un- 
  

   der 
  sand 
  plains 
  or 
  delta 
  deposits 
  accumulated 
  in 
  glacial 
  waters/ 
  The 
  

   axis 
  of 
  the 
  deepening 
  and 
  north 
  leading 
  valley 
  migrated 
  westward, 
  

   down 
  the 
  slope 
  of 
  the 
  basal 
  crystallines 
  and 
  against 
  the 
  outcrop 
  of 
  

   the 
  sediments. 
  

  

  The 
  great 
  ridge 
  dividing 
  the 
  Black 
  and 
  Ontario 
  valleys 
  now 
  

   terminates 
  abruptly 
  in 
  the 
  Rutland 
  promonton- 
  with 
  a 
  limestone 
  

   scarp 
  about 
  400 
  feet 
  high. 
  The 
  point 
  of 
  this 
  promontory 
  is 
  sho^vn 
  

   on 
  the 
  lower 
  edge 
  of 
  plate 
  44, 
  south 
  of 
  Felts 
  ^^lills 
  and 
  Black 
  River 
  

   villages. 
  A 
  glance 
  at 
  the 
  AVatertown 
  sheet 
  will 
  show 
  how 
  the 
  river 
  

   below 
  Felts 
  ^lills 
  clings 
  to 
  the 
  foot 
  of 
  the 
  scarp. 
  A 
  moment's 
  

   thought 
  will 
  make 
  it 
  evident 
  that 
  these 
  thick 
  limestones 
  did 
  not 
  

   originally 
  end 
  here, 
  but 
  must 
  have 
  extended 
  far 
  north, 
  overlying 
  the 
  

   district 
  toward 
  the 
  St 
  Lawrence. 
  It 
  seems 
  perfectly 
  e^-ident 
  that 
  

   the 
  stratigraphic 
  relations 
  and 
  the 
  erosional 
  conditions 
  which 
  pro- 
  

   duced 
  the 
  Black 
  valley 
  above 
  Carthage 
  must 
  once 
  have 
  extended 
  

   much 
  farther 
  northward, 
  and 
  the 
  Tertiar}^ 
  river 
  probably 
  had 
  its 
  

   course 
  northward 
  along 
  what 
  is 
  now 
  the 
  east 
  slope 
  of 
  the 
  St 
  Law- 
  

   rence 
  valley, 
  in 
  continuation 
  of 
  the 
  Forestport-Carthage 
  valley. 
  The 
  

   problem 
  is 
  therefore 
  narrowed 
  to 
  the 
  question 
  of 
  the 
  time 
  of 
  the 
  

   removal 
  of 
  the 
  Trenton 
  limestones 
  north 
  of 
  the 
  Rutland 
  promon- 
  

   tory, 
  and 
  the 
  date 
  of 
  the 
  diversion 
  of 
  the 
  river 
  from 
  its 
  northward 
  

   into 
  its 
  westward 
  course. 
  

  

  A 
  singular 
  physiographic 
  feature 
  of 
  the 
  region 
  is 
  the 
  northward 
  

   or 
  rather 
  northeastward 
  direction 
  of 
  all 
  the 
  heavy 
  streams 
  north 
  

   of 
  the 
  Black 
  river. 
  These 
  all 
  flow 
  along 
  parallel 
  with 
  the 
  St 
  

   Lawrence, 
  and 
  in 
  some 
  sections 
  at 
  even 
  lower 
  levels. 
  In 
  normal 
  

   stream 
  development 
  the 
  tributaries 
  should 
  flow 
  toward 
  the 
  trunk 
  

   stream. 
  The 
  Indian, 
  Oswegatchie, 
  Grass, 
  Raquette 
  and 
  St 
  Regis 
  

   are 
  more 
  or 
  less 
  independent 
  of 
  the 
  St 
  Lawrence 
  and 
  are 
  not 
  normal 
  

   tributaries. 
  Their 
  courses 
  have 
  probably 
  been 
  modified, 
  straight- 
  

   ened 
  and 
  their 
  parallelism 
  emphasized 
  by 
  repeated 
  glaciation, 
  but 
  

   the 
  latest 
  ice 
  erosion 
  has 
  certainly 
  been 
  insufficient 
  to 
  produce 
  such 
  

   channels. 
  Their 
  direction 
  is 
  in 
  precise 
  opposition 
  to 
  the 
  glacial 
  

   eftect 
  and 
  also 
  in 
  opposition 
  to 
  the 
  postglacial 
  uplift 
  of 
  the 
  region. 
  

   It 
  is 
  in 
  harmony 
  with 
  and 
  in 
  continuation 
  of 
  the 
  Black 
  valley, 
  

   curving 
  eastward 
  around 
  the 
  uplifted 
  mass 
  of 
  the 
  Adirondacks. 
  It 
  

   seems 
  altogether 
  likely 
  that 
  these 
  stream 
  courses 
  were 
  developed 
  

   by 
  north 
  leading 
  drainage 
  having 
  practically 
  the 
  same 
  stratigraphic 
  

  

  1 
  See 
  a 
  paper 
  by 
  the 
  writer, 
  Glacial 
  Waters 
  of 
  the 
  Black 
  and 
  ]Moha\vk 
  

   Valleys. 
  N. 
  Y. 
  State 
  Mus. 
  Bui. 
  In 
  press. 
  

  

  