﻿58 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Though 
  of 
  a 
  temporary 
  nature, 
  these 
  bodies 
  of 
  water 
  endured 
  suffi- 
  

   ciently 
  long 
  to 
  permit 
  the 
  formation 
  of 
  well 
  marked 
  beaches 
  with 
  

   their 
  accompaniment 
  of 
  bars, 
  sand-spits 
  and 
  other 
  wave-formed 
  

   features. 
  These 
  have 
  been 
  carefully 
  studied 
  and 
  mapped 
  by 
  a 
  num- 
  

   ber 
  of 
  observers, 
  and 
  the 
  general 
  extent 
  and 
  outline 
  of 
  these 
  lakes 
  

   is 
  today 
  pretty 
  accurately 
  determined. 
  

  

  The 
  largest 
  of 
  these 
  glacial 
  lakes, 
  though 
  not 
  the 
  first 
  to 
  come 
  

   into 
  existence, 
  was 
  glacial 
  Lake 
  Warren. 
  *'At 
  its 
  maximum 
  extent 
  

   Lake 
  Warren 
  covered 
  the 
  south 
  half 
  of 
  Lake 
  Huron, 
  including 
  

   Saginaw 
  bay, 
  the 
  whole 
  of 
  Lake 
  Erie 
  and 
  the 
  low 
  ground 
  between 
  

   it 
  and 
  Lake 
  Huron; 
  extended 
  eastward 
  to 
  within 
  twenty 
  or 
  thirty 
  

   miles 
  of 
  Syracuse, 
  N. 
  Y. 
  and 
  probably 
  covered 
  some 
  of 
  the 
  western 
  

   end 
  of 
  Lake 
  Ontario." 
  ^ 
  The 
  retaining 
  ice 
  wall 
  on 
  the 
  east 
  ex- 
  

   tended 
  in 
  a 
  northwesterly 
  direction, 
  across 
  western 
  New 
  York,. 
  

   Lake 
  Ontario- 
  and 
  the 
  northeastern 
  end 
  of 
  Lake 
  Huron. 
  This 
  

   position 
  of 
  the 
  ice 
  front 
  is 
  in 
  part 
  inferred 
  from 
  the 
  existence 
  of 
  

   moraines 
  of 
  sand 
  and 
  gravel 
  along 
  a 
  portion 
  of 
  that 
  line. 
  The 
  

   total' 
  area 
  of 
  this 
  ancient 
  lake 
  has 
  been 
  variously 
  estimated 
  as 
  in- 
  

   cluding 
  from 
  one 
  hundred 
  thousand 
  to 
  two 
  hundred 
  thousand 
  

   square 
  miles 
  of 
  surface 
  but 
  this 
  estimate 
  is 
  based 
  on 
  the 
  assump- 
  

   tion 
  that 
  the 
  lake 
  occupied 
  the 
  greater 
  part 
  of 
  the 
  area 
  of 
  the 
  

   present 
  upper 
  Great 
  lakes, 
  with 
  the 
  intervening 
  land, 
  a 
  supposition 
  

   which 
  Taylor 
  holds 
  to 
  be 
  incorrect. 
  The 
  area 
  of 
  Lake 
  Warren 
  

   was 
  probably 
  less 
  than 
  50,000 
  square 
  miles, 
  or 
  approximately 
  half 
  

   that 
  of 
  the 
  state 
  of 
  Kansas. 
  The 
  extent 
  and 
  level 
  of 
  this 
  lake 
  was 
  

   not 
  constant, 
  there 
  being 
  many 
  oscillations, 
  due 
  chiefly 
  to 
  warpings 
  

   of 
  the 
  land 
  surface. 
  These 
  oscillations 
  are 
  recorded 
  in 
  the 
  various, 
  

   beaches 
  which 
  have 
  remained 
  to 
  the 
  present 
  time. 
  The 
  chief 
  outlet 
  

   of 
  Lake 
  Warren 
  was 
  by 
  way 
  of 
  the 
  Grand 
  river 
  valley 
  into 
  the 
  

   valley 
  of 
  Lake 
  Michigan, 
  the 
  southern 
  end 
  of 
  which 
  was 
  then 
  much 
  

   expanded 
  and 
  occupied 
  by 
  the 
  waters 
  of 
  " 
  Lake 
  Chicago." 
  The 
  

   outflow 
  of 
  this 
  lake 
  was 
  to 
  the 
  Mississippi 
  by 
  way 
  of 
  the 
  Illinois, 
  

   river, 
  across 
  the 
  divide 
  near 
  where 
  Chicago 
  now 
  stands, 
  thus 
  tem- 
  

   porarily 
  reestablishing 
  the 
  southward 
  drainage 
  of 
  this 
  region. 
  

  

  'Taylor. 
  A 
  short 
  history 
  of 
  the 
  Great 
  lakes, 
  p. 
  loi. 
  

  

  