﻿48 
  TWENTY-FIRST 
  REPORT 
  ON 
  THE 
  STATE 
  CABINET. 
  

  

  the 
  counties 
  of 
  Argenteuil 
  and 
  Grenville, 
  to 
  form 
  three 
  distinct 
  

   formations, 
  having 
  each 
  a 
  thickness 
  of 
  from 
  1,000 
  to 
  1,500 
  feet, 
  

   separated, 
  underlaid 
  and 
  overlaid 
  by 
  still 
  greater 
  masses 
  of 
  gneiss 
  

   and 
  quartzite. 
  The 
  measured 
  thickness 
  of 
  this 
  series 
  on 
  the 
  

   Ottawa 
  is 
  more 
  than 
  20,000 
  feet, 
  which 
  is 
  probably 
  far 
  from 
  repre- 
  

   senting 
  its 
  total 
  volume, 
  while 
  in 
  Bohemia 
  it 
  is 
  supposed 
  to 
  equal 
  

   not 
  less 
  than 
  90,000 
  feet. 
  In 
  the 
  county 
  of 
  Hastings, 
  in 
  the 
  pro- 
  

   vince 
  of 
  Ontario, 
  not 
  less 
  than 
  21,000 
  feet 
  of 
  strata, 
  consisting 
  of 
  

   crystalline 
  schists, 
  limestones 
  and 
  diorites, 
  are 
  found 
  resting 
  con- 
  

   formably 
  upon 
  Laurentian 
  gneiss. 
  * 
  It 
  appears 
  certain, 
  however, 
  

   that 
  this 
  series, 
  which 
  differs 
  both 
  in 
  the 
  succession 
  and 
  the 
  litho- 
  

   logical 
  character 
  of 
  its 
  strata 
  from 
  the 
  sections 
  in 
  the 
  Ottawa 
  

   valley, 
  belong* 
  to 
  the 
  Lower 
  Laurentian, 
  of 
  which 
  it 
  would 
  appear 
  

   to 
  constitute 
  a 
  member 
  higher 
  in 
  the 
  system 
  than 
  any 
  observed 
  in 
  

   New 
  York 
  or 
  in 
  the 
  province 
  of 
  Quebec, 
  so 
  that 
  the 
  whole 
  known 
  

   thickness 
  of 
  the 
  Lower 
  Laurentian 
  in 
  Canada 
  would 
  surpass 
  40,000 
  

   feet. 
  The 
  Eozoon 
  Canadense 
  is 
  met 
  with 
  in 
  several 
  localities, 
  both 
  

   in 
  the 
  lower 
  and 
  higher 
  members 
  of 
  the 
  Lower 
  Laurentian. 
  

  

  The* 
  Labrador 
  (or 
  Upper 
  Laurentian) 
  occurs 
  in 
  detached 
  areas, 
  

   resting 
  unconformably 
  upon 
  the 
  true 
  Laurentian 
  system. 
  Some 
  

   of 
  these 
  areas 
  are 
  many 
  miles 
  in 
  breadth, 
  and 
  they 
  occur 
  at 
  

   intervals 
  in 
  Canada 
  from 
  the 
  shores 
  of 
  Lake 
  Huron 
  to 
  the 
  coast 
  of 
  

   Labrador. 
  The 
  Labrador 
  series 
  contains 
  strata 
  of 
  orthoclase 
  

   gneiss, 
  quartzites, 
  and 
  crystalline 
  limestones 
  ; 
  but 
  its 
  predomi- 
  

   nant 
  element 
  is 
  an 
  anortholite 
  — 
  a 
  rock 
  composed 
  essentially 
  of 
  a 
  

   feldspar 
  of 
  the 
  anorthic 
  or 
  triclinic 
  system, 
  generally 
  with 
  a 
  small 
  

   admixture 
  of 
  pyroxene 
  or 
  hypersthene. 
  This 
  anortholite 
  is 
  some- 
  

   times 
  gneissoid, 
  and 
  even 
  fine-grained 
  ; 
  but 
  is 
  more 
  often 
  granitoid, 
  

   and 
  occasionally 
  presents 
  large 
  ckavable 
  masses 
  of 
  opalescent 
  

   feldspar, 
  generally 
  labradorite 
  or 
  andesine. 
  The 
  thickness 
  of 
  this 
  

   Labrador 
  series 
  cannot 
  be 
  less 
  than 
  10,000 
  feet, 
  and 
  is 
  perhaps 
  

   much 
  more. 
  The 
  true 
  Laurentian 
  offers 
  nothing 
  similar 
  to 
  these 
  

   anortholites, 
  which 
  seem 
  to 
  be 
  identical, 
  both 
  lithologically 
  and 
  

   geognostically, 
  with 
  the 
  norites 
  of 
  Norway. 
  They 
  are 
  the 
  hyper- 
  

   stheuites 
  of 
  the 
  Hebrides, 
  described 
  by 
  McCulloch, 
  and 
  subse- 
  

   quently 
  recognized 
  by 
  Emmons 
  under 
  the 
  name 
  of 
  hypersthene 
  

   rock 
  in 
  the 
  Adirondacks, 
  of 
  which, 
  according 
  to 
  him, 
  they 
  form 
  

   some 
  of 
  the 
  highest 
  summits. 
  

  

  To 
  these 
  two 
  great 
  series 
  of 
  ancient 
  rocks 
  must 
  be 
  added 
  a 
  

   third 
  — 
  the 
  Huronian, 
  which 
  attains 
  on 
  Lake 
  Huron 
  a 
  thickness 
  of 
  

  

  * 
  See 
  postscript 
  on 
  page 
  98. 
  

  

  