﻿50 
  TWENTY-FIRST 
  REPORT 
  ON 
  THE 
  STATE 
  CABINET. 
  

  

  ley 
  of 
  the 
  Ottawa, 
  left, 
  as 
  we 
  have 
  seen, 
  no 
  doubt 
  of 
  their 
  sedi- 
  

   mentary 
  nature 
  and 
  origin. 
  Similar 
  limestones 
  in 
  the 
  Highlands 
  

   of 
  New 
  York 
  and 
  New 
  Jersey 
  were 
  long 
  since 
  recognized 
  by 
  

   Rogers, 
  by 
  Mather, 
  and 
  by 
  other 
  American 
  geologists, 
  as 
  in 
  like 
  

   manner 
  altered 
  stratified 
  rocks, 
  which 
  were 
  by 
  some 
  regarded 
  as 
  

   of 
  Silurian 
  age, 
  and 
  by 
  others 
  of 
  greater 
  antiquity. 
  The 
  obser- 
  

   vations 
  made 
  by 
  Sir 
  William 
  Logan 
  and 
  Prof. 
  James 
  Hall, 
  in 
  

   1864 
  [Amen 
  Jour. 
  Science 
  [2], 
  xxxix, 
  97), 
  in 
  the 
  Highlands 
  of 
  

   the 
  Hudson, 
  however, 
  leave 
  no 
  doubt 
  that 
  these 
  limestones, 
  and 
  

   their 
  accompanying 
  gneissoid 
  strata, 
  belong 
  to 
  the 
  Laurentian 
  

   system. 
  

  

  The 
  study 
  by 
  the 
  late 
  Dr. 
  Emmons 
  of 
  the 
  similar 
  series 
  of 
  rocks, 
  

   constituting 
  the 
  mountain 
  region 
  of 
  the 
  Adironclacks 
  in 
  northern 
  

   New 
  York, 
  and 
  continuous 
  with 
  the 
  great 
  Laurentian 
  area 
  of 
  

   Canada, 
  led 
  him, 
  however, 
  to 
  regard 
  the 
  limestones 
  of 
  the 
  series 
  

   as 
  of 
  igneous 
  origin, 
  and 
  in 
  fact 
  as 
  intrusive 
  rocks. 
  (See 
  his 
  

   Report 
  on 
  the 
  Geology 
  of 
  the 
  First 
  District 
  of 
  New 
  York, 
  pub- 
  

   lished 
  in 
  1842, 
  pages 
  37-59.) 
  This 
  view, 
  although 
  in 
  contradic- 
  

   tion 
  with 
  the 
  conclusions 
  of 
  other 
  geologists 
  who 
  have 
  examined 
  

   these 
  Laurentian 
  limestones 
  in 
  Canada 
  and 
  the 
  United 
  States, 
  was 
  

   not 
  so 
  singular 
  as 
  might 
  at 
  first 
  sight 
  appear. 
  Mather, 
  in 
  his 
  

   Report 
  on 
  Second 
  District 
  of 
  New 
  York 
  (page 
  485), 
  while 
  main- 
  

   taining 
  the 
  sedimentary 
  and 
  metamorphic 
  nature 
  of 
  the 
  crystalline 
  

   limestones 
  of 
  the 
  Highlands, 
  asserted 
  that 
  there 
  were 
  examples 
  in 
  

   Washington 
  county 
  fully 
  sustaining 
  Emmons' 
  view 
  that 
  such 
  

   limestones 
  sometimes 
  occur 
  as 
  eruptive 
  rocks. 
  

  

  Many 
  of 
  the 
  first 
  geologists 
  of 
  other 
  countries 
  have 
  also 
  main- 
  

   tained 
  the 
  igneous 
  origin 
  of 
  certain 
  crystalline 
  limestones. 
  Thus, 
  

   in 
  1863, 
  we 
  find 
  Von 
  Leon 
  hard 
  asserting 
  that 
  limestones 
  have 
  

   sometimes 
  come 
  from 
  the 
  interior 
  of 
  the 
  earth 
  in 
  a 
  liquid 
  state, 
  like 
  

   other 
  igneous 
  rocks. 
  A 
  similar 
  view 
  was 
  at 
  that 
  time 
  maintained 
  

   by 
  Guidini 
  with 
  regard 
  to 
  the 
  dolomites 
  of 
  Spezzia 
  in 
  northern 
  

   Italy, 
  and 
  by 
  Rozet 
  for 
  similar 
  rocks 
  at 
  Oran 
  in 
  Algeria, 
  and 
  for 
  

   the 
  crystalline 
  limestones 
  of 
  the 
  Vosges, 
  which, 
  like 
  those 
  of 
  the 
  

   Laurentian 
  series, 
  occur 
  in 
  gneiss, 
  and 
  are 
  often 
  mingled 
  with 
  ser- 
  

   pentine. 
  {Bull. 
  Soc. 
  Geol. 
  de 
  France, 
  iii, 
  pages 
  215 
  and 
  235.) 
  

   These 
  observers, 
  like 
  Dr. 
  Emmons, 
  urged 
  in 
  support 
  of 
  their 
  view, 
  

   among 
  other 
  reasons 
  more 
  or 
  less 
  fallacious, 
  the 
  undoubted 
  fact 
  

   that 
  such 
  limestones, 
  in 
  some 
  cases, 
  apparently 
  form 
  dykes 
  or 
  

   veins, 
  which, 
  like 
  those 
  of 
  granite 
  and 
  greenstone, 
  traverse 
  gneissic 
  

   or 
  quartzose 
  strata. 
  

  

  