﻿626 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  pebbles, 
  which 
  becomes 
  converted 
  into 
  a 
  hard 
  stone 
  layer, 
  the 
  inside 
  

   remaining 
  usually 
  unconsolidated. 
  When 
  in 
  after 
  time 
  these 
  

   nodules 
  are 
  wrested 
  from 
  the 
  bed 
  in 
  wliich 
  they 
  originate, 
  they 
  are 
  

   broken 
  open, 
  the 
  clayey 
  or 
  sometimes 
  sandy 
  interior 
  waslies 
  out 
  and 
  

   there 
  is 
  left 
  a 
  potlike, 
  hollow 
  pebble 
  of 
  the 
  kind 
  known 
  as 
  aetites 
  or 
  

   eaglestone.^ 
  Hundreds 
  of 
  these 
  nodules 
  were 
  dragged 
  out 
  of 
  their 
  

   bedding 
  places 
  by 
  the 
  advance 
  of 
  the 
  ice 
  over 
  the 
  Columbia 
  at 
  the 
  

   time 
  of 
  making 
  tlie 
  terminal 
  moraine 
  on 
  Marthas 
  Yineyard 
  and 
  in 
  

   portions 
  of 
  Long 
  Island. 
  

  

  Tlie 
  occurrence 
  of 
  these 
  nodules 
  at 
  the 
  locality 
  mentioned 
  affords 
  

   evidence 
  that 
  the 
  underlying 
  white 
  clays 
  and 
  sandy 
  clays 
  were 
  

   eroded 
  at 
  the 
  beginning 
  of 
  Columbia 
  deposition. 
  The 
  uncon- 
  

   formity 
  thus 
  inferred 
  is 
  widespread 
  to 
  the 
  east 
  on 
  Marthas 
  Yine- 
  

   yard 
  and 
  Block 
  island 
  and 
  along 
  the 
  Atlantic 
  coast 
  southward 
  to 
  

   the 
  vicinity 
  of 
  Washington. 
  Of 
  direct 
  local 
  evidence, 
  little 
  can 
  be 
  

   said. 
  On 
  tlie 
  shore 
  north 
  of 
  Coldspring 
  the 
  gravelly 
  beds 
  at 
  the 
  

   base 
  of 
  the 
  tilted 
  Pleistocene 
  series 
  may 
  be 
  seen 
  resting 
  on 
  the 
  

   Cretaceous 
  and 
  older 
  clays, 
  but 
  there 
  is 
  no 
  observed 
  difference 
  of 
  

   dip, 
  though 
  the 
  absence 
  of 
  identifiable 
  Eocene 
  or 
  Neocene 
  beds 
  is 
  

   proof 
  of 
  an 
  unconformity. 
  JSTo 
  clearer 
  fact 
  than 
  this 
  was 
  gathered 
  

   from 
  the 
  similar 
  sections 
  about 
  frlen 
  Cove 
  and 
  Glenwood. 
  

  

  Aside 
  from 
  this 
  unmistakable 
  instance 
  of 
  older 
  gravels 
  lying 
  out- 
  

   side 
  of 
  the 
  moraine, 
  it 
  is 
  uncertain 
  to 
  what 
  extent 
  the 
  older 
  beds 
  make 
  

   up 
  the 
  frontal 
  plain. 
  Yellowish 
  gravels 
  abound 
  in 
  tlie 
  road 
  and 
  

   railroad 
  cuts, 
  but 
  the 
  yellow 
  quartz 
  pebbles 
  have 
  invariably 
  been 
  

   W/ashed 
  and 
  worn 
  since 
  they 
  were 
  stained, 
  and 
  similar 
  pebbles 
  are 
  

   now 
  working 
  tlieir 
  way 
  from 
  the 
  cliffs 
  down 
  the 
  beach 
  slopes 
  into 
  

   the 
  deposits 
  now 
  making 
  along 
  the 
  coast. 
  It 
  is 
  to 
  be 
  inferred, 
  how- 
  

   ever, 
  from 
  the 
  attitude 
  and 
  thickness 
  of 
  the 
  Columbia 
  north 
  of 
  the 
  

   moraine 
  that 
  a 
  large 
  part 
  of 
  the 
  section 
  south- 
  of 
  the 
  moraine 
  is 
  

   composed 
  of 
  these 
  beds. 
  

  

  The 
  structure 
  of 
  these 
  beds 
  is 
  revealed 
  in 
  only 
  a 
  few 
  pits 
  and 
  

   coastal 
  sections. 
  The 
  most 
  extensive 
  exposures 
  in 
  1900 
  were 
  found 
  

   in 
  a 
  number 
  of 
  sand 
  pits 
  on 
  the 
  west 
  shore 
  of 
  Hempstead 
  harbor. 
  

   In 
  these 
  pits 
  the 
  beds 
  are 
  horizontal, 
  and 
  the 
  boulder 
  clay 
  bed 
  is 
  

   clearly 
  traceable. 
  

  

  1 
  Geikie, 
  A. 
  Textbook 
  of 
  geology. 
  3d 
  ed. 
  1893. 
  p. 
  146-47. 
  

  

  