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  Brigham 
  — 
  Drift 
  Bowlders 
  in 
  Central 
  New 
  York. 
  

  

  id 
  embers 
  weather 
  to 
  monotonous 
  browns 
  and 
  grays 
  and 
  would 
  

   need 
  careful 
  attention 
  to 
  their 
  fossil 
  contents 
  for 
  trustworthy 
  

   identification. 
  

  

  The 
  dip 
  of 
  these 
  beds, 
  in 
  connection 
  with 
  the 
  dissection 
  of 
  

   the 
  region 
  into 
  north 
  and 
  south 
  trenches 
  and 
  ridges, 
  is 
  an 
  

   essential 
  fact 
  in 
  the 
  study 
  of 
  vertical 
  distribution, 
  or 
  of 
  the 
  

   plucking 
  action 
  of 
  the 
  ice. 
  The 
  several 
  terranes 
  first 
  appear, 
  

   as 
  one 
  goes 
  southward, 
  in 
  northward 
  loops 
  on 
  the 
  hills, 
  and 
  

   disappear 
  as 
  southward 
  loops 
  in 
  the 
  valleys. 
  Yanuxem 
  cites 
  a 
  

   measurement 
  for 
  the 
  Corniferous 
  near 
  Waterville, 
  as 
  27 
  feet 
  

   per 
  mile 
  S. 
  W. 
  The 
  Oriskany 
  sandstone 
  at 
  Oriskany 
  Falls 
  

   dips 
  47 
  feet 
  per 
  mile. 
  40 
  to 
  50 
  feet 
  per 
  mile, 
  S. 
  S. 
  W. 
  is 
  prob- 
  

   ably 
  a 
  safe 
  general 
  statement 
  for 
  the 
  region. 
  

  

  General 
  Movement 
  of 
  the 
  Ice. 
  — 
  Striae 
  observed 
  at 
  several 
  

   localities 
  indicate 
  that 
  the 
  main 
  movement 
  of 
  the 
  glacial 
  current 
  

   was 
  about 
  S. 
  20° 
  W. 
  This 
  conclusion 
  is 
  based 
  upon 
  comparison 
  

   and 
  averaging 
  of 
  movements 
  at 
  the 
  higher 
  altitudes, 
  and 
  where 
  

   local 
  topography 
  would 
  not 
  be 
  likely 
  to 
  modify 
  direction. 
  

   The 
  trend 
  may 
  have 
  been 
  largely 
  influenced 
  by 
  the 
  Adiron- 
  

   dacks 
  as 
  a 
  local 
  center 
  of 
  glaciation. 
  If 
  this 
  be 
  true, 
  a 
  S. 
  S. 
  W. 
  

   flow 
  along 
  the 
  Oriskany-Chenango 
  axis 
  is 
  radial 
  and 
  would 
  be 
  

   expected. 
  The 
  Hudson 
  .River 
  and 
  Oneida 
  bowlders 
  of 
  our 
  

   field 
  may 
  thus 
  have 
  been 
  plucked 
  from 
  the 
  vicinity 
  of 
  Utica 
  

   and 
  Rome, 
  although 
  some 
  were 
  doubtless 
  brought 
  in 
  by 
  cross 
  

   currents 
  from 
  more 
  easterly 
  and 
  westerly 
  points. 
  

  

  Archcean 
  Bowlders. 
  — 
  These 
  fragments 
  of 
  the 
  drift 
  are 
  in 
  

   the 
  usual 
  lithological 
  variety. 
  No 
  consideration 
  of 
  them 
  rela- 
  

   tive 
  to 
  their 
  sources, 
  can 
  be 
  had, 
  until 
  their 
  Adirondack 
  and 
  

   more 
  northerly 
  localities 
  shall 
  have 
  been 
  studied 
  in 
  detail.* 
  A 
  

   profusion 
  of 
  large 
  Archaean 
  masses 
  is 
  found 
  in 
  northern 
  Oneida 
  

   County, 
  over 
  the 
  Paleozoic 
  terranes 
  which 
  lie 
  within 
  a 
  few 
  

   miles 
  of 
  the 
  crystalline 
  areas. 
  For 
  some 
  miles 
  south 
  of 
  the 
  

   Mohawk, 
  pieces 
  having 
  diameters 
  of 
  four 
  feet 
  are 
  tolerably 
  

   frequent. 
  South 
  of 
  the 
  divide 
  such 
  fragments 
  are 
  rare. 
  A 
  

   few 
  comparisons 
  from 
  counts 
  and 
  estimates 
  made 
  in 
  the 
  field, 
  

   will 
  give 
  the 
  best 
  notion 
  of 
  the 
  facts. 
  Approaching 
  Oriskany 
  

   Falls 
  from 
  Clinton, 
  on 
  the 
  summit 
  of 
  the 
  range 
  to 
  the 
  west- 
  

   ward, 
  six 
  Archaean 
  pieces 
  were 
  observed 
  having 
  axes 
  of 
  four 
  

   to 
  six 
  feet. 
  These 
  and 
  many 
  smaller 
  ones 
  were 
  seen 
  in 
  increas- 
  

   ing 
  numbers 
  on 
  n 
  earing 
  the 
  line 
  of 
  the 
  moraine, 
  which 
  appears 
  

   in 
  its 
  full 
  strength 
  in 
  the 
  valley 
  at 
  the 
  above 
  village. 
  The 
  

   valley 
  moraine 
  itself 
  however, 
  consists 
  of 
  kames, 
  which 
  are 
  

   nearly 
  free 
  from 
  large 
  bowlders. 
  Thirty 
  feet 
  of 
  stone 
  wall 
  in 
  

   the 
  town 
  of 
  Madison, 
  showing 
  average 
  complexion 
  of 
  bowlders 
  

   of 
  the 
  adjacent 
  field, 
  give 
  the 
  following 
  result. 
  

  

  *For 
  notes 
  on 
  such 
  comparative 
  study, 
  see 
  G. 
  P. 
  Wright 
  on 
  the 
  Glacial 
  Boundary, 
  

   Bull. 
  58, 
  U. 
  S. 
  G. 
  S., 
  pp. 
  50-52. 
  

  

  