﻿10 
  W. 
  UpKam 
  — 
  Chamjplain 
  Subsidence 
  and 
  

  

  about 
  135 
  miles 
  north 
  to 
  Lake 
  Nipissing 
  it 
  descends 
  at 
  an 
  

   average 
  rate 
  of 
  about 
  eight 
  inches 
  per 
  mile. 
  

  

  While 
  the 
  eastern 
  part 
  of 
  the 
  Lake 
  Algonquin 
  area 
  was 
  

   being 
  much 
  uplifted, 
  with 
  the 
  formation 
  of 
  other 
  beaches 
  be- 
  

   low 
  the 
  first, 
  probably 
  the 
  southern 
  part 
  of 
  the 
  Lake 
  Michigan 
  

   basin 
  remained 
  with 
  a 
  very 
  slight 
  change 
  of 
  attitude 
  or 
  none, 
  

   having 
  previously 
  risen 
  to 
  approximately 
  its 
  present 
  height, 
  

   which 
  it 
  has 
  since 
  held 
  with 
  little 
  or 
  no 
  change. 
  But 
  the 
  

   northeastward 
  elevation 
  raising 
  the 
  country 
  where 
  Lake 
  Al- 
  

   gonquin 
  and 
  now 
  Lake 
  Huron 
  have 
  outflowed, 
  gradually 
  

   caused 
  the 
  water 
  level 
  at 
  Chicago 
  to 
  rise 
  some 
  40 
  feet 
  above 
  

   its 
  old 
  Algonquin 
  level, 
  which 
  is 
  shown 
  by 
  a 
  sublacustrine 
  

   terrace 
  formed 
  by 
  the 
  Algonquin 
  wave 
  erosion 
  and 
  beach 
  

   accumulation. 
  

  

  On 
  the 
  Saugeen 
  river, 
  Ontario, 
  and 
  near 
  the 
  south 
  end 
  of 
  

   Georgian 
  bay, 
  fresh-water 
  shells 
  are 
  found 
  in 
  beds 
  belonging 
  

   to 
  stages 
  of 
  Lake 
  Algonquin 
  respectively 
  about 
  40 
  and 
  100 
  

   feet 
  below 
  the 
  main 
  and 
  earliest 
  Algonquin 
  beach, 
  or 
  90 
  and 
  

   78 
  feet 
  above 
  the 
  present 
  lake 
  and 
  bay. 
  

  

  Lake 
  Lundy* 
  — 
  From 
  the 
  Forest 
  beach 
  at 
  Crittenden, 
  Erie 
  

   county, 
  N. 
  Y., 
  marking 
  the 
  latest 
  level 
  of 
  Lake 
  Warren, 
  there 
  

   is 
  a 
  descent 
  of 
  125 
  feet 
  between 
  860 
  and 
  735 
  feet 
  above 
  the 
  

   sea 
  to 
  the 
  earliest 
  strand 
  of 
  the 
  glacial 
  Lake 
  Lundy, 
  which 
  for 
  

   a 
  time 
  occupied 
  the 
  northeastern 
  three-fourths 
  of 
  the 
  Lake 
  

   Erie 
  basin. 
  A 
  more 
  conspicuous 
  principal 
  Lundy 
  beach, 
  30 
  

   feet 
  lower, 
  on 
  which 
  is 
  the 
  "ridge 
  road" 
  named 
  Lundy 
  lane, 
  

   near 
  Niagara 
  Falls, 
  has 
  an 
  eastward 
  ascent 
  of 
  30 
  feet 
  in 
  about 
  

   40 
  miles 
  from 
  Font-hill, 
  Ont., 
  to 
  Akron, 
  N. 
  Y., 
  live 
  miles 
  

   north 
  of 
  Crittenden. 
  Lake 
  Lundy 
  opened 
  through 
  a 
  strait 
  

   about 
  30 
  miles 
  wide 
  into 
  the 
  Lake 
  Ontario 
  basin. 
  Its 
  outflow 
  

   passed 
  eastward, 
  across 
  the 
  country 
  close 
  north 
  of 
  the 
  Finger 
  

   lakes, 
  to 
  the 
  Mohawk 
  and 
  Hudson 
  valleys, 
  still 
  partly 
  tilled 
  

   by 
  the 
  receding 
  ice-sheet 
  and 
  permitting 
  a 
  series 
  of 
  mouths 
  of 
  

   Lake 
  Lundy 
  to 
  be 
  found 
  at 
  successively 
  lower 
  levels, 
  until 
  as 
  

   the 
  ice-border 
  withdrew 
  the 
  water 
  soon 
  sank 
  to 
  the 
  lowest 
  

   point 
  of 
  the 
  Ontario-Mohawk 
  watershed 
  at 
  Rome, 
  ~N. 
  Y., 
  

   where 
  its 
  level 
  long 
  remained, 
  forming 
  the 
  Iroquois 
  beach. 
  One 
  

   of 
  the 
  stages 
  of 
  the 
  sinking 
  Lake 
  Lundy 
  or 
  incipient 
  Lake 
  Iro- 
  

   quois, 
  probably 
  nearly 
  midway 
  in 
  altitude 
  between 
  the 
  Lundy 
  

   and 
  Iroquois 
  beaches, 
  I 
  find 
  to 
  be 
  indicated 
  by 
  my 
  studies 
  of 
  

   eskers 
  in 
  Rochester 
  and 
  Pittsford, 
  N. 
  Y.f 
  

  

  * 
  J. 
  W. 
  Spencer, 
  " 
  Deformation 
  of 
  the 
  Lundy 
  Beach 
  and 
  Birth 
  of 
  Lake 
  Erie," 
  

   this 
  Journal, 
  III, 
  vol. 
  xlvii, 
  pp. 
  207-211, 
  with 
  map, 
  March, 
  1894. 
  

  

  f 
  Proceedings 
  of 
  the 
  Rochester 
  Academy 
  of 
  Science, 
  vol. 
  ii, 
  pp. 
  196-198, 
  Jan., 
  

   1893. 
  

  

  

  