﻿OF 
  THE 
  LAKE- 
  BASINS 
  OF 
  CUMBERLAND. 
  101 
  

  

  another 
  ice 
  -stream 
  flowing 
  northwards 
  down 
  Mosedale 
  from 
  Gale 
  Fell 
  

   (see 
  Map, 
  PI. 
  IX.). 
  Any 
  part 
  of 
  the 
  ice-mass 
  thus 
  got 
  rid 
  of 
  from 
  

   the 
  main 
  valley 
  at 
  this 
  point, 
  however, 
  was 
  probably 
  more 
  than 
  

   made 
  up 
  for 
  by 
  the 
  ice 
  poured 
  down 
  from 
  the 
  flanks 
  of 
  the 
  Grasmoor 
  

   and 
  Whiteless 
  Pike 
  range. 
  Between 
  the 
  northern 
  end 
  of 
  Mellbreak 
  

   and 
  Grasmoor, 
  the 
  valley 
  is 
  again 
  considerably 
  reduced 
  in 
  width 
  ; 
  and 
  

   along 
  this 
  lower 
  half 
  of 
  the 
  lake 
  its 
  depth 
  is 
  greatest. 
  Escaped 
  from 
  

   this 
  narrow 
  part, 
  the 
  main 
  mass 
  of 
  the 
  glacier 
  continued 
  down 
  the 
  

   vale 
  of 
  Lorton, 
  reinforced 
  by 
  ice 
  shed 
  off 
  from 
  the 
  west 
  sides 
  of 
  the 
  

   lofty 
  Grasmoor 
  and 
  Whiteside 
  range 
  ; 
  and 
  it 
  is 
  certain 
  that 
  at 
  one 
  

   time, 
  at 
  any 
  rate, 
  the 
  left 
  limb 
  of 
  the 
  glacier 
  passed 
  over 
  the 
  present 
  

   site 
  of 
  Loweswater, 
  and 
  partly 
  enveloped 
  Low 
  Fell. 
  This 
  must 
  

   have 
  been 
  at 
  a 
  time 
  when 
  the 
  outward 
  thrust 
  of 
  the 
  ice 
  was 
  suffi- 
  

   ciently 
  powerful 
  to 
  push 
  a 
  portion 
  of 
  the 
  glacier 
  westward 
  up 
  an 
  

   incline 
  of 
  75 
  feet 
  in 
  a 
  distance 
  of 
  a 
  mile 
  and 
  a 
  half, 
  from 
  Crum- 
  

   mock 
  to 
  Loweswater 
  (fig. 
  2). 
  At 
  the 
  east 
  end 
  of 
  Loweswater 
  other 
  

   ice-streams 
  from 
  the 
  south 
  met 
  this 
  branch 
  of 
  the 
  main 
  glacier 
  ; 
  and 
  

   the 
  whole 
  mass 
  was 
  squeezed 
  through 
  the 
  narrow 
  valley 
  between 
  

   Carling 
  Knott 
  and 
  Low 
  Fell 
  (fig. 
  10), 
  in 
  which 
  Loweswater 
  now 
  

   lies, 
  its 
  deepest 
  part 
  (60 
  feet) 
  being 
  midway 
  between 
  these 
  highest 
  

   points 
  (fig. 
  21). 
  A 
  mile 
  and 
  a 
  quarter 
  beyond 
  the 
  upper 
  end 
  of 
  

   Loweswater 
  the 
  ice 
  would 
  pass 
  over 
  the 
  low 
  watershed 
  at 
  Sosgill 
  

   (fig. 
  2) 
  into 
  the 
  flat 
  country 
  beyond. 
  

  

  I 
  think 
  that 
  when 
  the 
  following 
  points 
  are 
  carefully 
  considered 
  

   — 
  the 
  fact 
  of 
  the 
  lakes 
  under 
  examination 
  being 
  but 
  long 
  shallow 
  

   troughs, 
  the 
  thickness 
  of 
  the 
  glaciers 
  which 
  moved 
  along 
  the 
  valleys 
  

   in 
  which 
  the 
  lakes 
  now 
  lie, 
  the 
  agreement 
  of 
  the 
  deepest 
  parts 
  of 
  

   the 
  lakes 
  with 
  the 
  points 
  at 
  which, 
  from 
  the 
  confluence 
  of 
  several 
  

   ice-streams 
  and 
  the 
  narrowing 
  of 
  the 
  valley, 
  the 
  onward 
  pressure 
  of 
  

   the 
  ice 
  must 
  have 
  been 
  greatest 
  — 
  one 
  can 
  hardly 
  resist 
  the 
  conclu- 
  

   sion 
  that 
  the 
  immediate 
  cause 
  of 
  these 
  lake-basins 
  was 
  the 
  onward 
  

   movement 
  of 
  the 
  old 
  glaciers, 
  ploughing 
  up 
  their 
  beds 
  to 
  this 
  slight 
  

   depth, 
  in 
  the 
  way 
  Professor 
  Ramsay's 
  theory 
  suggests. 
  At 
  the 
  

   same 
  time 
  it 
  should 
  be 
  noticed 
  that 
  in 
  the 
  case 
  of 
  Buttermere 
  and 
  

   Crummock 
  — 
  lying 
  in 
  a 
  valley 
  with 
  rounded 
  bottom, 
  as 
  seen 
  in 
  cross 
  

   sections 
  — 
  the 
  action 
  is 
  merely 
  a 
  slight 
  deepening 
  of 
  the 
  basin, 
  or 
  the 
  

   formation 
  of 
  a 
  smaller 
  basin 
  of 
  similar 
  general 
  form 
  at 
  the 
  bottom 
  

   of 
  the 
  larger 
  ; 
  whereas 
  in 
  the 
  case 
  of 
  Derwentwater 
  and 
  Bassen- 
  

   thwaite 
  the 
  action 
  has 
  been 
  to 
  produce 
  a 
  long 
  shallow 
  groove, 
  of 
  

   varying 
  width, 
  upon 
  the 
  flat 
  bottom 
  of 
  the 
  wide 
  pan-like 
  valley 
  — 
  

   this 
  groove 
  in 
  the 
  case 
  of 
  Bassenthwaite 
  being 
  situated 
  (for 
  pro- 
  

   bable 
  reasons 
  before 
  noticed) 
  markedly 
  at 
  one 
  side 
  of 
  the 
  pan, 
  close 
  

   under 
  the 
  rising 
  sides. 
  

  

  It 
  may 
  be 
  urged 
  by 
  some 
  that 
  the 
  fact 
  of 
  the 
  deeper 
  lakes 
  being 
  

   situated 
  in 
  the 
  valley 
  bearing 
  the 
  glacier 
  of 
  least 
  thickness 
  is 
  against 
  

   the 
  idea 
  of 
  the 
  lake-basins 
  being 
  formed 
  by 
  the 
  ice 
  ; 
  but 
  I 
  think, 
  in 
  

   this 
  case, 
  the 
  fact 
  is 
  rather 
  due 
  to 
  the 
  original 
  forms 
  of 
  the 
  respec- 
  

   tive 
  valleys, 
  the 
  same 
  or 
  a 
  less 
  amount 
  of 
  rock-scooping 
  giving 
  rise 
  

   to 
  a 
  deeper 
  lake 
  in 
  an 
  originally 
  round-bottomed 
  valley 
  than 
  in 
  a 
  

   fiat-bottomed 
  one. 
  

  

  