﻿46 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Upham,^ 
  at 
  a 
  depth 
  of 
  more 
  than 
  400 
  feet 
  below 
  Lake 
  Erie. 
  Whether 
  

   this 
  marks 
  the 
  former 
  southward 
  continuation 
  of 
  the 
  preglacial 
  

   Dundas 
  river 
  or 
  whether 
  that 
  river 
  turned 
  more 
  to 
  the 
  west, 
  follow- 
  

   ing 
  in 
  general 
  the 
  course 
  of 
  the 
  present 
  Maumee, 
  must 
  for 
  the 
  pres- 
  

   ent 
  remain 
  unsettled. 
  The 
  Dundas 
  undoubtedly 
  became 
  eventually 
  

   tributary 
  to 
  the 
  Mississippi. 
  

  

  Preglacial 
  Saginaw 
  river. 
  The 
  existence 
  of 
  an 
  ancient 
  river, 
  

   flowing 
  southwestward 
  from 
  the 
  Canadian 
  old-land 
  across 
  the 
  vrJley 
  

   of 
  Lake 
  Huron 
  and 
  the 
  lower 
  peninsula 
  of 
  Michigan, 
  and 
  finally 
  

   becoming 
  tributary 
  to 
  the 
  ancient 
  Mississippi, 
  is 
  indicated 
  by 
  the 
  

   present 
  character 
  of 
  the 
  topography 
  of 
  that 
  region. 
  The 
  Niagara 
  

   cuesta 
  is 
  breached 
  by 
  a 
  deep 
  channel 
  which 
  now 
  connects 
  Georgian 
  

   bay 
  with 
  Lake 
  Huron, 
  and 
  which, 
  north 
  of 
  Cove 
  island, 
  an 
  outlier 
  

   from 
  the 
  Indian 
  peninsula, 
  has 
  been 
  sounded 
  to 
  a 
  depth 
  of 
  over 
  300 
  

   feet. 
  This 
  channel 
  is 
  in 
  direct 
  line 
  with 
  that 
  of 
  Saginaw 
  bay, 
  and, 
  

   though 
  this 
  latter 
  is 
  at 
  present 
  very 
  shallow, 
  borings 
  at 
  Bay 
  City 
  

   show 
  an 
  absence 
  of 
  rock 
  to 
  a 
  depth 
  of 
  at 
  least 
  200 
  feet 
  below 
  the 
  

   surface 
  of 
  the 
  bay. 
  At 
  Alma 
  (Mich.) 
  the 
  rock 
  was 
  shown 
  to 
  be 
  

   absent 
  to 
  a 
  depth 
  of 
  350 
  feet 
  below 
  Lake 
  Huron 
  (Spencer); 
  and, 
  

   as 
  this 
  locality 
  lies 
  to 
  the 
  southwest 
  of 
  Saginaw 
  bay 
  and 
  in 
  line 
  with 
  

   the 
  trend 
  of 
  its 
  axis, 
  we 
  may 
  assume 
  that 
  our 
  preglacial 
  Saginaw 
  

   river 
  was 
  located 
  here. 
  Our 
  limited 
  knowledge 
  of 
  the 
  preglacial 
  

   topography 
  of 
  this 
  region 
  forbids 
  tracing 
  this 
  channel 
  beyond 
  this 
  

   point. 
  Dr 
  Spencer 
  many 
  years 
  ago 
  traced 
  out 
  this 
  line 
  of 
  drainage, 
  

   but 
  he 
  assumed 
  that 
  the 
  river 
  which 
  occupied 
  this 
  channel, 
  and 
  

   which 
  he 
  has 
  named 
  Huronian, 
  flowed 
  northeastward 
  to 
  join 
  that 
  

   part 
  of 
  the 
  ancient 
  St 
  Lawrence, 
  or 
  Laurentian 
  river, 
  which 
  he 
  sup- 
  

   posed 
  to 
  have 
  occupied 
  Georgian 
  bay. 
  

  

  Preglacial 
  consequent 
  Genesee 
  river. 
  An:iong 
  the 
  numerous 
  con- 
  

   sequent 
  streams 
  which 
  flowed 
  from 
  the 
  old-land 
  southward 
  or 
  

   southwestward 
  and 
  which 
  eventually 
  became 
  tributary 
  to 
  the 
  pre- 
  

   glacial 
  Mississippi, 
  probably 
  through 
  the 
  ancient 
  Ohio,^ 
  the 
  pre- 
  

  

  ^Bul. 
  geol. 
  soc. 
  Am. 
  8: 
  7. 
  

  

  ^Westgate, 
  Lewis. 
  Geographical 
  development 
  of 
  the 
  eastern 
  part 
  of 
  the 
  

   Mississippi 
  drainage 
  system. 
  Am. 
  geol. 
  1893. 
  11:245-60. 
  The 
  Ohio, 
  ac- 
  

   cording 
  to 
  Newberry, 
  flows 
  nearly 
  throughout 
  its 
  entire 
  course 
  in 
  a 
  

   channel, 
  the 
  rock 
  bottom 
  of 
  which 
  is 
  nowhere 
  less 
  than 
  150 
  feet 
  below 
  

   the 
  present 
  river. 
  The 
  rocks 
  at 
  the 
  " 
  falls 
  of 
  the 
  Ohio 
  " 
  show 
  that 
  at 
  that 
  

   point 
  the 
  river 
  is 
  not 
  following 
  the 
  ancient 
  course. 
  

  

  