﻿484 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  frequent 
  in 
  St 
  Lawrence 
  and 
  Lewis 
  counties 
  conform 
  in 
  every 
  

   way 
  to 
  what 
  would 
  be 
  expected 
  of 
  igneous 
  gneisses. 
  

  

  As 
  in 
  many 
  cases 
  direct 
  evidence 
  will 
  probably 
  never 
  be 
  found 
  

   to 
  prove 
  the 
  origin 
  of 
  these 
  gneisses, 
  it 
  will 
  be 
  necessary 
  to 
  arrive 
  

   at 
  conclusions 
  in 
  regard 
  to 
  the 
  problem 
  by 
  the 
  study 
  of 
  analogous 
  

   rocks, 
  which 
  like 
  the 
  syenite 
  give 
  evidence 
  of 
  their 
  origin. 
  From 
  

   what 
  has 
  thus 
  far 
  been 
  done 
  in 
  the 
  region 
  the 
  writer 
  believes 
  

   that 
  close* 
  study 
  of 
  typical 
  examples 
  of 
  igneous 
  and 
  of 
  sedimen- 
  

   tary 
  gneisses 
  will 
  furnish 
  data 
  on 
  which, 
  in 
  most 
  cases, 
  wholly 
  

   justifiable 
  conclusions 
  as 
  to 
  origin 
  may 
  be 
  based. 
  But 
  there 
  

   will 
  always 
  remain 
  a 
  group 
  of 
  intermediate 
  character 
  whose 
  

   origin 
  will 
  be 
  doubtful.* 
  New 
  and 
  more 
  refined 
  methods 
  of- 
  in- 
  

   vestigation 
  may 
  narrow 
  the 
  limits 
  of 
  this 
  group, 
  but 
  that 
  it 
  will 
  

   ever 
  be 
  obliterated 
  seems 
  at 
  present 
  improbable. 
  

  

  As 
  stated 
  in 
  the 
  beginning 
  of 
  this 
  report, 
  there 
  is 
  a 
  marked 
  

   contrast 
  between 
  the 
  rocks 
  on 
  the 
  northern 
  and 
  southern 
  sides 
  

   of 
  the 
  Diana-Pitcairn 
  limestone 
  belt. 
  The 
  former 
  region 
  shows 
  

   great 
  variety, 
  the 
  latter 
  much 
  sameness. 
  No 
  effort 
  has 
  been 
  

   made 
  to 
  straighten 
  out 
  the 
  tangle 
  of 
  intrusive 
  rocks, 
  igneous 
  

   and 
  sedimentary 
  gneisses 
  and 
  limestones 
  which 
  appear 
  in 
  the 
  

   irregular 
  hills, 
  cliffs 
  and 
  minor 
  valleys 
  north 
  of 
  the 
  limestone 
  

   belt. 
  On 
  the 
  whole 
  the 
  area 
  bordering 
  on 
  the 
  belt 
  and 
  extending 
  

   back 
  three 
  or 
  four 
  miles 
  is 
  the 
  most 
  varied 
  and 
  complex 
  that 
  

   the 
  writer 
  has 
  seen 
  in 
  the 
  Adirondack 
  region. 
  To 
  map 
  it 
  with 
  

   any 
  approach 
  to 
  accuracy 
  will 
  require 
  a 
  large 
  scale 
  base-map 
  and 
  

   much 
  careful 
  work. 
  Only 
  a 
  few 
  facts 
  need 
  be 
  recorded 
  here, 
  

   and, 
  owing 
  to 
  the 
  very 
  brief 
  examination 
  of 
  this 
  portion 
  of 
  the 
  

   region, 
  they 
  are 
  quite 
  disconnected. 
  

  

  About 
  two 
  miles 
  north 
  of 
  Harrisville 
  the 
  Gouverneur 
  road 
  

   crosses 
  Jenny 
  creek. 
  Just 
  beyond 
  the 
  crossing 
  a 
  good 
  granite 
  

   limestone 
  contact 
  is 
  exposed 
  in 
  the 
  road, 
  while 
  to 
  the 
  east 
  a 
  

   high, 
  steep 
  ridge 
  of 
  gray 
  granite 
  rises. 
  While 
  consisting 
  essen- 
  

   tially 
  of 
  granite, 
  the 
  ridge 
  shows 
  numerous 
  outcroppings 
  of 
  lime- 
  

   stone 
  scattered 
  irregularly 
  over 
  it. 
  These 
  patches 
  of 
  limestone 
  

   are 
  clearly 
  inclusions 
  in 
  the 
  granite 
  and 
  are 
  more 
  or 
  less 
  affected 
  

   by 
  metamorphic 
  agents. 
  In 
  general 
  the 
  grain 
  is 
  very 
  coarse 
  

  

  