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  Spencer 
  — 
  Origin 
  and 
  Age 
  of 
  the 
  Ontario 
  Shore-Line. 
  

  

  Island, 
  the 
  outer 
  margin 
  of 
  which 
  is 
  10,800 
  feet 
  from 
  the 
  

   shore 
  (section 
  A, 
  tig. 
  2). 
  At 
  the 
  shore, 
  only 
  a 
  few 
  feet 
  of 
  

   sand 
  cover 
  the 
  basement 
  shales, 
  but 
  at 
  the 
  outer 
  edge 
  of 
  the 
  

   island 
  variable 
  beds 
  of 
  sand 
  with 
  clay 
  (180 
  feet) 
  rest 
  on 
  transi- 
  

   tion 
  and 
  clay 
  beds 
  to 
  a 
  depth 
  of 
  230 
  feet, 
  overlying 
  the 
  base- 
  

   ment 
  shales. 
  Their 
  origin 
  is 
  complex. 
  Only 
  the 
  upper 
  30 
  

   feet 
  are 
  composed 
  of 
  coarse 
  sands 
  and 
  gravels, 
  washed 
  as 
  are 
  

   beach 
  materials. 
  These 
  alone 
  can 
  be 
  regarded 
  as 
  belonging 
  to 
  

   the 
  Ontario 
  beach, 
  and 
  their 
  thickness 
  corresponds 
  to 
  the 
  

   maximum 
  depth 
  of 
  the 
  bay 
  behind 
  the 
  island. 
  JBelow 
  are 
  10 
  

   feet 
  of 
  transition 
  beds 
  with 
  some 
  clay, 
  which 
  limit 
  the 
  water- 
  

   bearing 
  strata. 
  Beneath, 
  are 
  100 
  feet 
  of 
  variable 
  beds 
  of 
  very 
  

   tine 
  sand 
  and 
  clayey 
  sands, 
  not 
  well-washed. 
  These 
  rest 
  upon 
  

   very 
  fine, 
  closely 
  packed 
  sand 
  without 
  clay 
  (40 
  feet), 
  beneath 
  

   which 
  is 
  a 
  transition 
  bed 
  of 
  clay 
  nodules 
  in 
  sand 
  (10 
  feet) 
  over- 
  

   lying 
  40 
  feet 
  of 
  blue 
  clay 
  beds 
  covering 
  the 
  basement 
  shales,* 
  

   The 
  tine 
  clayey 
  sands 
  below 
  the 
  coarse 
  beach 
  sands 
  are 
  the 
  

   covered 
  post-Iroquois 
  delta 
  deposits 
  of 
  the 
  Don 
  River. 
  

  

  The 
  Toronto 
  beach, 
  in 
  front 
  of 
  Ashbridge 
  Bay 
  and 
  Toronto 
  

   Harbour, 
  is 
  a 
  barrier 
  nearly 
  6 
  miles 
  long, 
  leaving 
  the 
  main 
  

   lake 
  shore 
  near 
  the 
  Woodbine 
  (see 
  map, 
  tig. 
  1). 
  By 
  comparing 
  

   the 
  various 
  maps 
  of 
  it, 
  made 
  since 
  1788, 
  the 
  beach 
  is 
  seen 
  to 
  

   have 
  had 
  a 
  rapid 
  westward 
  growth 
  — 
  the 
  waves 
  building 
  up 
  a 
  

   succession 
  of 
  spurs 
  and 
  hooks, 
  with 
  intervening 
  ponds 
  and 
  

   marshes, 
  until 
  they 
  coalesced 
  (see 
  tig. 
  3). 
  Early 
  in 
  the 
  Nine- 
  

   teenth 
  Century 
  the 
  western 
  end 
  of 
  the 
  Harbour 
  was 
  open. 
  

   Here 
  a 
  spur, 
  4,000 
  feet 
  long, 
  was 
  developed 
  between 
  1841 
  and 
  

  

  1882 
  (forming 
  Hanlan's 
  bay 
  ; 
  see 
  B, 
  tig. 
  3). 
  In 
  1854, 
  the 
  west- 
  

   ern 
  end 
  of 
  the 
  Harbour 
  was 
  being 
  further 
  silted 
  up 
  so 
  as 
  to 
  

   occasion 
  concern. 
  In 
  1891, 
  and 
  again 
  in 
  1912, 
  piers 
  were 
  con- 
  

   structed 
  for 
  keeping 
  open 
  the 
  deepened 
  western 
  channel, 
  now 
  

   otherwise 
  closed. 
  The 
  materials 
  for 
  the 
  westward 
  growth 
  of 
  

   the 
  barrier 
  have 
  been 
  mostly 
  obtained 
  by 
  robbing 
  the 
  southern 
  

   shore 
  of 
  the 
  beach. 
  

  

  About 
  1850, 
  the 
  waves 
  forced 
  a 
  passage 
  between 
  the 
  lake 
  

   and 
  the 
  bay 
  (B, 
  fig. 
  3). 
  This 
  was 
  further 
  opened 
  in 
  1852, 
  

   '3 
  and 
  '5, 
  when 
  a 
  steamer 
  passed 
  through. 
  The 
  gap 
  was 
  closed 
  

   in 
  1856 
  owing 
  to 
  low 
  water, 
  but 
  it 
  became 
  permanent 
  in 
  1857. 
  

   By 
  1882 
  the 
  beach 
  had 
  been 
  washed 
  away 
  for 
  a 
  length 
  of 
  

   1,800 
  feet 
  and 
  a 
  depth 
  of 
  5 
  feet, 
  leaving 
  the 
  site 
  of 
  the 
  tavern 
  

   of 
  1841 
  some 
  hundreds 
  of 
  feet 
  outward 
  in 
  the 
  lake, 
  as 
  also 
  the 
  

   triangulation 
  station 
  of 
  1818. 
  Thus, 
  Toronto 
  Island 
  became 
  

   separated 
  from 
  the 
  peninsula 
  at 
  dates 
  mentioned. 
  No 
  con- 
  

   siderable 
  amount 
  of 
  drift 
  from 
  the 
  east 
  re-entered 
  the 
  gap. 
  In 
  

  

  1883 
  the 
  channel 
  through 
  it 
  was 
  deepened 
  by 
  a 
  canal 
  and 
  the 
  

  

  *This 
  geological 
  section 
  was 
  obtained 
  from 
  borings 
  at 
  the 
  Filter 
  basin, 
  

   near 
  the 
  southwestern 
  point 
  of 
  the 
  barrier 
  beach. 
  

  

  