﻿REPORT 
  OF 
  THE 
  DIRECTOR 
  

  

  r81 
  

  

  (b), 
  General 
  marginal 
  lakes 
  formed 
  along 
  the 
  marginal 
  con- 
  

   tact 
  of 
  the 
  stagnant 
  ice 
  lobe 
  and 
  the 
  land, 
  where 
  the 
  

   wastage 
  wonld 
  naturally 
  take 
  place 
  and 
  be 
  further 
  facilitated. 
  

   Two 
  such 
  zones 
  would 
  be 
  established, 
  oue 
  on 
  each 
  side, 
  

   with 
  the 
  ice-mass 
  occupying 
  the 
  middle 
  of 
  the 
  valley, 
  

   separating 
  the 
  two 
  water 
  ways, 
  which 
  have 
  no 
  apparent 
  

   connection 
  with 
  each 
  other, 
  except 
  for 
  a 
  slight 
  areal 
  con- 
  

   tact 
  at 
  the 
  frontal 
  edge, 
  where 
  wastage 
  always 
  takes 
  place. 
  

   If 
  their 
  contact 
  is 
  formed 
  and 
  an 
  outlet 
  is 
  found 
  at 
  the 
  

   divide, 
  it 
  will 
  serve 
  as 
  a 
  common 
  overflow 
  to 
  both 
  water- 
  

   bodies. 
  Otherwise, 
  there 
  must 
  exist 
  two 
  separate 
  and 
  dis- 
  

   tinct 
  overflow 
  channels, 
  if 
  the 
  lakes 
  are 
  drained. 
  

  

  Fig. 
  i6 
  

  

  Diagrammatic 
  cross-section 
  of 
  a 
  valley 
  (a 
  a 
  a), 
  partially 
  filled 
  with 
  a 
  stagnant 
  ice 
  tongue 
  or 
  lobe, 
  

   marked 
  ice. 
  Lateral 
  drainage 
  along 
  ice 
  and 
  land 
  contact, 
  showing 
  deposit 
  at 
  (b 
  b). 
  The 
  deposits, 
  

   may 
  or 
  maj' 
  not 
  have 
  the 
  same 
  correlative 
  heights. 
  

  

  Assuming 
  this 
  to 
  represent 
  the 
  true 
  condition, 
  it 
  is 
  evident 
  that 
  

   the 
  glacial 
  drainage 
  would 
  be 
  confined 
  to 
  channel 
  ways, 
  existing 
  

   between 
  the 
  land 
  and 
  ice, 
  where 
  the 
  in-pouring 
  streams 
  would 
  

   transport 
  their 
  load, 
  and 
  under 
  favorable 
  conditions 
  would 
  neces- 
  

   sarily 
  deposit 
  most, 
  if 
  not 
  all 
  of 
  it, 
  along 
  the 
  drainage 
  ways, 
  which 
  

   at 
  best 
  would 
  be 
  irregular 
  and 
  confined 
  exclusively 
  to 
  the 
  valley 
  

   sides. 
  The 
  thicker 
  the 
  ice 
  mass, 
  the 
  higher 
  up 
  the 
  valley 
  side.', 
  

   would 
  the 
  drdina2:e 
  be 
  established. 
  This 
  condition 
  might 
  endure 
  

   until 
  the 
  ice 
  had 
  completely 
  liquefied. 
  The 
  absence 
  of 
  such 
  

   deposits 
  along 
  the 
  valley 
  sides 
  accumulated 
  by 
  and 
  in 
  water 
  bodies 
  

  

  