﻿690 
  Forty- 
  seventh 
  Report 
  on 
  the 
  State 
  Museum. 
  

  

  was 
  deemed 
  inadvisable 
  to 
  attempt 
  any 
  very 
  close 
  work. 
  

   As 
  it 
  now 
  stands 
  the 
  map 
  gives, 
  with 
  fair 
  accuracy, 
  the 
  

   distribution 
  of 
  gneiss 
  and 
  limestone, 
  though 
  there 
  are 
  several 
  

   doubtful 
  points 
  along 
  the 
  northern 
  edge. 
  The 
  more 
  import- 
  

   ant 
  areas 
  of 
  sandstone 
  and 
  granite 
  appear, 
  their 
  precise 
  extent 
  

   and 
  outline 
  not 
  often 
  being 
  shown, 
  while 
  doubtless 
  a 
  large 
  

   number 
  of 
  minor 
  patches 
  are 
  wholly 
  omitted. 
  In 
  fact, 
  the 
  

   areas 
  of 
  sandstone 
  and 
  granite 
  are 
  so 
  irregular 
  in 
  distribution, 
  

   outline 
  and 
  extent 
  that 
  every 
  square 
  rod 
  of 
  the 
  region 
  would 
  

   have 
  to 
  be 
  traversed 
  to 
  ensure 
  their 
  accurate 
  representation. 
  

  

  In 
  the 
  course 
  of 
  the 
  mapping 
  it 
  was 
  clearly 
  ascertained 
  that 
  a 
  

   portion 
  of 
  the 
  gneiss 
  is 
  interbedded 
  with 
  the 
  limestone, 
  and 
  in 
  

   every 
  instance 
  observed 
  this 
  gneiss 
  is 
  of 
  the 
  well 
  laminated 
  

   variety. 
  Similar 
  laminated 
  gneiss 
  is 
  usually 
  seen 
  in 
  passing 
  

   from 
  the 
  limestone 
  to 
  the 
  large 
  gneiss 
  areas. 
  This 
  is 
  well 
  shown 
  

   near 
  the 
  Old 
  Sterling 
  mine 
  in 
  Antwerp, 
  at 
  Keene's 
  Station 
  and 
  

   in 
  Hailesboro, 
  two 
  miles 
  south 
  of 
  Gouverneur. 
  The 
  gneiss 
  as 
  

   seen 
  on 
  its 
  northern 
  edge 
  is 
  finely 
  laminated, 
  often 
  crumpled, 
  

   and 
  contains 
  garnet 
  or 
  sillimanite 
  or 
  both. 
  Going 
  southward 
  

   toward 
  the 
  center 
  of 
  the 
  gneiss 
  area, 
  the 
  rock 
  becomes 
  more 
  

   massive 
  and 
  coarse 
  grained, 
  in 
  places 
  decidedly 
  granitic, 
  and 
  at 
  

   some 
  points 
  shows 
  coarse 
  porphyritic 
  phases 
  and 
  " 
  augen-gneiss." 
  

   As 
  before 
  said, 
  this 
  is 
  the 
  common 
  character 
  of 
  the 
  passage 
  from 
  

   limestone 
  to 
  gneiss, 
  but 
  there 
  are 
  many 
  1< 
  calities 
  where 
  the 
  

   laminated 
  gneiss 
  is 
  wholly 
  wanting, 
  the 
  limestone 
  being 
  in 
  

   contact 
  with 
  the 
  massive 
  gneiss. 
  

  

  From 
  their 
  character 
  and 
  position 
  it 
  would 
  seem 
  that 
  all 
  of 
  

   the 
  laminated 
  gneisses 
  must 
  be 
  regarded 
  as 
  belonging 
  with 
  the 
  

   limestone, 
  as 
  members 
  of 
  a 
  series 
  of 
  uncertain, 
  but 
  very 
  con- 
  

   siderable 
  thickness, 
  unconformable 
  beneath 
  the 
  Potsdam. 
  It 
  

   will 
  be 
  convenient 
  for 
  reference 
  and, 
  according 
  to 
  the 
  writer's 
  

   opinion, 
  in 
  the 
  interest 
  of 
  exact 
  terminology, 
  to 
  give 
  to 
  this 
  

   series 
  a 
  local 
  name 
  rather 
  than 
  to 
  employ 
  an 
  assumed 
  correla- 
  

   tion 
  with 
  other 
  regions, 
  which 
  is 
  not 
  yet 
  established. 
  As 
  the 
  

   Oswegatchie 
  river 
  flows 
  many 
  miles 
  through 
  these 
  rocks 
  the 
  

   name 
  Oswegatchie 
  series 
  is 
  suggested 
  as 
  particularly 
  appropriate. 
  

  

  As 
  to 
  the 
  origin 
  of 
  the 
  rocks 
  there 
  seems 
  to 
  be 
  no 
  reason 
  for 
  

   considering 
  them 
  other 
  than 
  true 
  sediments, 
  though 
  extreme 
  

   metamorphism 
  has 
  removed 
  all 
  trace 
  of 
  clastic 
  structure. 
  At 
  

  

  