﻿658 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  sequent 
  closing 
  might 
  under 
  the 
  local 
  circumstances 
  have 
  accom- 
  

   plished, 
  as 
  in 
  existing 
  glaciers, 
  such 
  minor 
  changes 
  of 
  water 
  level.^ 
  

   A 
  glance 
  at 
  the 
  topographic 
  map 
  will 
  show 
  that 
  from 
  Flushing 
  

   bay, 
  the 
  shore 
  line 
  of 
  which 
  at 
  the 
  time 
  the 
  College 
  Point 
  delta 
  

   was 
  deposited 
  must 
  have 
  been 
  about 
  40 
  feet 
  higher 
  than 
  now, 
  there 
  

   is 
  a 
  well 
  defined 
  channel 
  extending 
  westward 
  from 
  Newton 
  through 
  

   Winfield 
  Junction 
  to 
  the 
  head 
  of 
  ]N"ewtown 
  creek. 
  From 
  this 
  point 
  

   escape 
  of 
  the 
  water 
  to 
  or 
  connection 
  with 
  the 
  sea 
  was 
  possible 
  

   either 
  along 
  the 
  northwestward 
  course 
  of 
  J^ewtown 
  creek 
  to 
  the 
  

   East 
  river 
  at 
  Hunters 
  point 
  or, 
  if 
  that 
  way 
  was 
  still 
  blocked 
  by 
  the 
  

   ice 
  sheet, 
  along 
  a 
  more 
  southerly 
  course 
  between 
  Williamsburg 
  and 
  

   Brooklyn 
  into 
  Wallabout 
  bay, 
  the 
  highest 
  land 
  there 
  lying 
  between 
  

   the 
  20 
  foot 
  and 
  40 
  foot 
  contours. 
  From 
  Wallabout 
  bay 
  a 
  somewhat 
  

   winding 
  passage 
  below 
  the 
  40 
  foot 
  level 
  was 
  open, 
  permitting 
  dis- 
  

   charge 
  into 
  or 
  connection 
  with 
  Gowanus 
  bay 
  just 
  north 
  of 
  the 
  

  

  moraine 
  at 
  the 
  J^arrows. 
  

  

  As 
  for 
  the 
  possibility 
  

  

  of 
  the 
  40 
  foot 
  delta 
  at 
  

   College 
  Point 
  having 
  

   been 
  deposited 
  at 
  sea- 
  

   level, 
  it 
  should 
  be 
  

  

  Fig. 
  9 
  Cross-section 
  of 
  the 
  structures 
  observed 
  in 
  the 
  Col- 
  Stated 
  that 
  similar 
  f 
  Or- 
  

   lege 
  Point 
  delta, 
  a, 
  fore-set 
  beds; 
  6, 
  top 
  set 
  beds; 
  c, 
  , 
  • 
  j.i 
  i? 
  j.i 
  

  

  morainal 
  ridge 
  or 
  bar 
  matlOnS 
  north 
  of 
  the 
  

  

  moraine 
  indicate 
  wide- 
  

   spread 
  waters 
  at 
  about 
  this 
  level. 
  When 
  these 
  have 
  been 
  fully 
  

   investigated 
  it 
  may 
  be 
  necessary 
  to 
  admit 
  a 
  submergence 
  to 
  this 
  

   extent. 
  What 
  is 
  stated 
  here 
  must 
  be 
  taken 
  with 
  this 
  reservation 
  

   in 
  mind. 
  

  

  ^ 
  See, 
  on 
  the 
  formation 
  of 
  temporary 
  lakes 
  at 
  the 
  present 
  time, 
  Edouard 
  Suess, 
  

   La 
  face 
  de 
  la 
  terre. 
  Paris, 
  1900. 
  2 
  : 
  590-97, 
  and 
  the 
  authors 
  there 
  cited; 
  also 
  De 
  

   Lapparent, 
  Traite 
  de 
  geologic. 
  4me 
  ed. 
  Paris, 
  1900. 
  p. 
  303-3, 
  on 
  the 
  sudden 
  

   drainage 
  of 
  glacial 
  lakes. 
  For 
  American 
  glacial 
  lakes 
  of 
  the 
  class 
  here 
  described,. 
  

   see 
  H. 
  B. 
  Ktimmell, 
  Lake 
  Passaic, 
  an 
  extinct 
  glacial 
  lake, 
  in 
  IST. 
  J. 
  geol. 
  sur. 
  

   an. 
  rep't 
  for 
  1893. 
  Trenton 
  1894. 
  p. 
  225-328; 
  separately 
  printed 
  1895. 
  p. 
  1-89; 
  

   Crosby 
  and 
  Grabau, 
  Glacial 
  lake 
  deposits 
  near 
  Boston, 
  Science. 
  1896. 
  3 
  : 
  212- 
  

   13; 
  also 
  Grabau 
  in 
  Crosby's 
  Geology 
  of 
  the 
  Boston 
  basin. 
  1900. 
  v. 
  1, 
  pt 
  3, 
  

   p. 
  564-600, 
  pi. 
  25; 
  and 
  "Warren 
  Upham, 
  The 
  glacial 
  lake 
  Agassiz, 
  U. 
  S. 
  geol. 
  

   sur. 
  Monograph 
  25. 
  1895. 
  658 
  p. 
  

  

  