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  Brigham 
  — 
  Drift 
  Bowlders 
  in 
  Central 
  New 
  York. 
  

  

  that 
  the 
  variable 
  amount 
  of 
  iron 
  pyrites 
  in 
  the 
  Oneida 
  beds, 
  

   occasioned 
  the 
  breaking 
  up, 
  or 
  discoloration 
  of 
  some 
  pieces, 
  

   while 
  others, 
  shaped 
  and 
  deposited 
  at 
  an 
  earlier 
  date, 
  show 
  no 
  

   signs 
  of 
  change.* 
  

  

  Lower 
  Helderberg. 
  — 
  The 
  limestones 
  are 
  deeply 
  cut 
  by 
  the 
  

   several 
  valleys 
  at 
  about 
  the 
  position 
  of 
  the 
  moraine 
  belt 
  in 
  

   each, 
  though 
  not 
  in 
  all 
  cases 
  does 
  the 
  terrane 
  outcrop 
  above 
  

   the 
  glacial 
  debris, 
  except 
  farther 
  to 
  the 
  north 
  on 
  the 
  hill 
  sides 
  

   and 
  summits. 
  At 
  Oriskany 
  Falls, 
  120 
  feet 
  of 
  these 
  beds 
  are 
  

   exposed 
  on 
  the 
  west 
  side 
  of 
  the 
  valley, 
  in 
  quarries 
  and 
  natural 
  

   ledges. 
  40 
  feet 
  are 
  massive 
  beds, 
  the 
  rest 
  thin, 
  two 
  to 
  six 
  inches 
  

   in 
  thickness. 
  The 
  limestone 
  is 
  found 
  not 
  infrequently 
  in 
  

   slabs 
  and 
  rounded 
  masses 
  up 
  to 
  four 
  feet 
  in 
  breadth 
  or 
  diame- 
  

   ter. 
  This 
  is 
  true 
  for 
  only 
  six 
  to 
  eight 
  miles 
  from 
  the 
  outcrop 
  ; 
  

   and 
  it 
  is 
  only 
  for 
  this 
  distance 
  that 
  the 
  limestone 
  occurs 
  at 
  

   high 
  levels. 
  From 
  Hamilton 
  southward, 
  the 
  fragments 
  are 
  

   small 
  and 
  almost 
  confined 
  to 
  the 
  gravel 
  trains, 
  terraces 
  and 
  

   kames 
  of 
  the 
  valleys, 
  rarely 
  occurring 
  above 
  100 
  feet 
  from 
  the 
  

   valley 
  bottoms. 
  The 
  possible 
  causes 
  of 
  this 
  distribution 
  will 
  

   receive 
  further 
  inquiry 
  after 
  an 
  account 
  of 
  the 
  Oriskany 
  sand- 
  

   stone 
  has 
  been 
  given. 
  

  

  Oriskany 
  Sandstone. 
  — 
  The 
  outcrop, 
  from 
  which 
  the 
  New 
  

   York 
  geologists 
  named 
  this 
  terrane, 
  is 
  found 
  one 
  half 
  mile 
  

   north 
  of 
  Oriskany 
  Falls, 
  near 
  the 
  town 
  line 
  of 
  Augusta 
  and 
  

   Marshall, 
  Oneida 
  County. 
  It 
  appears 
  in 
  a 
  continuous 
  ledge, 
  

   three 
  fourths 
  of 
  a 
  mile 
  long 
  and 
  125 
  feet 
  above 
  the 
  Oriskany 
  

   Creek, 
  the 
  valley 
  wall 
  rising 
  still 
  400 
  feet 
  to 
  the 
  westward. 
  

   Below 
  it 
  lie 
  120 
  feet 
  of 
  Lower 
  Helderberg, 
  and 
  above 
  are 
  50 
  

   feet 
  or 
  more 
  of 
  Corniferous. 
  The 
  hill 
  range 
  is 
  capped 
  with 
  

   Marcellus 
  and 
  Hamilton. 
  The 
  general 
  trend 
  of 
  the 
  ledge 
  is 
  S. 
  

   23° 
  W. 
  The 
  sandstone 
  stands 
  out 
  to 
  its 
  full 
  thickness, 
  12 
  feet 
  

   at 
  the 
  north, 
  thinning 
  to 
  7 
  or 
  8 
  feet 
  at 
  the 
  south, 
  and 
  dipping 
  

   southward 
  about 
  47 
  feet 
  per 
  mile. 
  Below 
  the 
  sandstone 
  on 
  the 
  

   valley 
  side, 
  is 
  a 
  broad 
  shelf 
  of 
  Lower 
  Helderberg. 
  The 
  sand- 
  

   stone 
  forms 
  a 
  shelf 
  about 
  5 
  rods 
  wide, 
  quite 
  bare 
  except 
  where 
  

   disintegration 
  has 
  taken 
  place, 
  making 
  a 
  slight 
  cover 
  of 
  soil 
  

   and 
  vegetation. 
  The 
  rock 
  is 
  a 
  coarse 
  grained, 
  grayish 
  white 
  

   sandstone, 
  weathering 
  to 
  yellowish 
  brown, 
  with 
  certain 
  zones 
  

   full 
  of 
  pockets 
  from 
  which 
  the 
  characteristic 
  fossils 
  have 
  dis- 
  

   appeared 
  by 
  solution. 
  There 
  are 
  two 
  sets 
  of 
  joints, 
  S. 
  38°-48° 
  

   E. 
  and 
  S. 
  33°-38° 
  W. 
  The 
  joint 
  blocks 
  average 
  10 
  to 
  20 
  feet 
  

   in 
  breadth 
  and 
  length, 
  and 
  are 
  often 
  set 
  off, 
  from 
  a 
  few 
  inches 
  

   to 
  several 
  feet. 
  There 
  is 
  no 
  distinct 
  bedding 
  plane 
  except 
  at 
  

   the 
  top 
  and 
  bottom 
  of 
  the 
  mass. 
  The 
  passage 
  from 
  the 
  lime- 
  

   stone 
  below, 
  and 
  to 
  the 
  limestone 
  above, 
  is 
  sharp, 
  and 
  the 
  

  

  * 
  Suggested 
  to 
  the 
  writer 
  by 
  Professor 
  C. 
  H. 
  Smyth, 
  Jr. 
  

  

  