﻿Adams. 
  Barlow 
  and 
  Ells 
  — 
  Canadian 
  Laurentian. 
  179 
  

  

  south 
  of 
  the 
  St. 
  Lawrence 
  in 
  the 
  Adirondack 
  region, 
  and 
  are 
  

   now 
  being 
  mapped, 
  it 
  will 
  be 
  of 
  great 
  interest 
  to 
  ascertain 
  

   whether 
  the 
  same 
  relations 
  do 
  not 
  also 
  exist 
  in 
  that 
  area, 
  and 
  

   whether 
  a 
  continuation 
  of 
  the 
  Hastings 
  series 
  to 
  the 
  south 
  can- 
  

   not 
  be 
  recognized 
  in 
  the 
  " 
  Huronian 
  Schist 
  " 
  of 
  St. 
  Lawrence 
  

   and 
  Jefferson 
  counties, 
  shown 
  upon 
  the 
  Geological 
  Map 
  of 
  the 
  

   State 
  of 
  New 
  York, 
  which 
  has 
  just 
  been 
  issued 
  by 
  the 
  Geolog- 
  

   ical 
  Survey 
  of 
  this 
  State. 
  

  

  It 
  is 
  perhaps 
  unnecessary 
  to 
  draw 
  attention 
  to 
  the 
  fact 
  that 
  

   the 
  recent 
  investigations 
  of 
  Messrs. 
  Wolff, 
  Brooks, 
  Nason, 
  

   Kemp, 
  Westgate 
  and 
  others 
  on 
  the 
  crystalline 
  limestones 
  of 
  

   New 
  Jersey 
  have 
  a 
  certain 
  bearing 
  on 
  this 
  subject. 
  

  

  Eemarks 
  by 
  E. 
  W. 
  Ells 
  : 
  

  

  In 
  connection 
  with 
  the 
  statements 
  advanced 
  in 
  the 
  preceding 
  

   paper 
  by 
  Dr. 
  Adams 
  and 
  Mr. 
  Barlow, 
  it 
  is 
  but 
  right 
  that 
  the 
  

   conclusions 
  arrived 
  at 
  from 
  the 
  study 
  of 
  the 
  similar 
  rocks 
  in 
  

   their 
  eastern 
  and 
  northern 
  extension 
  should 
  be 
  stated. 
  The 
  

   investigations 
  in 
  this 
  quarter 
  have 
  now 
  been 
  carried 
  on 
  for 
  six 
  

   years, 
  and 
  have 
  extended 
  over 
  a 
  very 
  large 
  area 
  to 
  the 
  north 
  of 
  

   the 
  Ottawa, 
  in 
  which 
  is 
  included 
  the 
  typical 
  Grenville 
  series 
  

   of 
  Sir 
  "W. 
  E. 
  Logan, 
  and 
  extending 
  far 
  up 
  the 
  Gatineau 
  

   River 
  ; 
  while 
  to 
  the 
  westward, 
  the 
  work 
  has 
  been 
  carried 
  on 
  

   till 
  the 
  vicinity 
  of 
  the 
  area, 
  described 
  in 
  the 
  accompanying 
  

   paper, 
  has 
  been 
  reached. 
  It 
  may 
  be 
  said 
  therefore 
  that 
  the 
  

   detailed 
  examination 
  of 
  the 
  rocks 
  which 
  make 
  up 
  the 
  Gren- 
  

   ville 
  and 
  Hastings 
  series 
  has 
  extended 
  over 
  an 
  area 
  about 
  250 
  

   miles 
  in 
  length 
  by 
  75 
  miles 
  in 
  breadth. 
  

  

  In 
  the 
  early 
  days 
  of 
  the 
  study 
  of 
  these 
  rocks 
  much 
  difficulty 
  

   was 
  experienced. 
  Firstly 
  there 
  was 
  a 
  great 
  and 
  almost 
  inac- 
  

   cessible 
  wilderness, 
  the 
  only 
  available 
  means 
  of 
  travel 
  over 
  the 
  

   greater 
  portion 
  being 
  by 
  canoes 
  ; 
  and 
  in 
  the 
  second 
  place 
  there 
  

   was 
  an 
  almost 
  entire 
  lack 
  of 
  trained 
  observers 
  to 
  carry 
  on 
  the 
  

   work. 
  Add 
  to 
  this 
  the 
  entire 
  absence 
  of 
  microscopical 
  deter- 
  

   minations, 
  and 
  one 
  can 
  readily 
  comprehend 
  the 
  difficulty 
  expe- 
  

   rienced 
  in 
  the 
  attempt 
  to 
  solve 
  this 
  most 
  difficult 
  of 
  the 
  

   problems 
  in 
  Canadian 
  geology. 
  

  

  Foliation 
  and 
  stratilication 
  were 
  considered 
  conclusive 
  evi- 
  

   dence 
  of 
  sedimentation, 
  and 
  as 
  most 
  of 
  the 
  rocks 
  of 
  the 
  great 
  

   Laurentian 
  complex 
  gave 
  evidence 
  of 
  these 
  forms 
  of 
  structure, 
  

   the 
  inference 
  naturally 
  followed 
  that 
  the 
  greater 
  portion 
  of 
  

   the 
  gneissic, 
  granitic 
  and 
  anorthositic 
  rocks 
  were 
  of 
  sedimen- 
  

   tary 
  origin. 
  So 
  far 
  was 
  this 
  sedimentary 
  theory 
  carried 
  out 
  

   that, 
  in 
  the 
  earlier 
  reports 
  of 
  the 
  Geological 
  Survey, 
  even 
  the 
  

   masses 
  of 
  binary 
  granite 
  and 
  many 
  of 
  the 
  pyroxenic 
  rocks 
  were 
  

   included 
  in 
  the 
  same 
  category. 
  This 
  was 
  at 
  the 
  time 
  a 
  very 
  

   natural 
  conclusion, 
  since 
  many 
  of 
  these 
  masses 
  have 
  a 
  regular 
  

   bedded 
  structure 
  and 
  conform, 
  over 
  very 
  considerable 
  areas, 
  to 
  

   the 
  regular 
  stratification 
  of 
  the 
  rocks, 
  either 
  gneiss 
  or 
  crystal- 
  

   line 
  limestone. 
  As 
  the 
  country 
  became 
  more 
  accessible 
  the 
  

  

  