﻿452 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  [June 
  22, 
  

  

  6. 
  On 
  the 
  Former 
  Existence 
  of 
  Glaciers 
  in 
  the 
  High 
  Grounds 
  of 
  

   the 
  South 
  of 
  Scotland. 
  By 
  John 
  Young, 
  M.D., 
  F.R.S.E., 
  of 
  the 
  

   Geological 
  Survey 
  of 
  Great 
  Britain. 
  

  

  [Communicated 
  by 
  Archibald 
  Geikie, 
  Esq., 
  F.G.S.] 
  

  

  The 
  heights 
  bordering 
  the 
  counties 
  of 
  Peebles 
  and 
  Dumfries 
  con- 
  

   tain 
  the 
  well-preserved 
  remains 
  of 
  a 
  group 
  of 
  Glaciers, 
  to 
  one 
  of 
  

   which 
  Mr. 
  Chambers 
  published, 
  in 
  1855, 
  a 
  brief 
  allusion*. 
  In 
  the 
  

   autumn 
  of 
  1862 
  Mr. 
  Geikie 
  and 
  myself 
  found 
  moraines 
  in 
  several 
  of 
  

   the 
  valleys 
  of 
  this 
  district, 
  and 
  the 
  description 
  of 
  them 
  given 
  by 
  my 
  

   colleague 
  in 
  his 
  paper 
  on 
  " 
  The 
  Phenomena 
  of 
  the 
  Glacial 
  Drift 
  in 
  

   Scotland 
  " 
  is 
  the 
  first 
  published 
  account 
  of 
  Glaciers 
  occurring 
  south 
  

   of 
  the 
  Clyde 
  f. 
  Last 
  summer 
  the 
  investigation 
  of 
  this 
  district 
  by 
  

   the 
  Geological 
  Survey 
  began 
  : 
  I 
  had 
  the 
  advantage 
  for 
  a 
  short 
  time 
  

   of 
  Mr. 
  Geikie's 
  advice 
  and 
  assistance, 
  and 
  am 
  further 
  indebted 
  to 
  

   him 
  for 
  the 
  Sketch 
  in 
  Talla 
  Yalley 
  (fig. 
  3), 
  as 
  well 
  as 
  for 
  much 
  of 
  the 
  

   details 
  regarding 
  Loch 
  Skene 
  and 
  Mid 
  Law 
  Den, 
  of 
  which 
  he 
  pre- 
  

   pared, 
  in 
  1862, 
  the 
  Map 
  accompanying 
  this 
  paper 
  (fig. 
  2). 
  

  

  The 
  Tweed 
  and 
  Yarrow 
  flowing 
  northwards, 
  and 
  the 
  Annan 
  and 
  

   Moffat 
  waters 
  flowing 
  south, 
  rise 
  on 
  opposite 
  sides 
  of 
  a 
  watershed, 
  

   of 
  which 
  Hartfell 
  and 
  Whitecoomb 
  are 
  the 
  highest 
  points. 
  The 
  two 
  

   former 
  rivers 
  meet 
  near 
  Selkirk, 
  the 
  two 
  latter 
  converge 
  below 
  the 
  

   town 
  of 
  Moffat, 
  8 
  and 
  12 
  miles 
  respectively 
  from 
  their 
  sources. 
  The 
  

   country 
  included 
  between 
  these 
  river- 
  valleys 
  forms 
  the 
  highest 
  range 
  

   in 
  the 
  Silurian 
  tract 
  of 
  the 
  South 
  of 
  Scotland. 
  The 
  Broad 
  Law, 
  

   2754 
  ft., 
  is 
  the 
  centre 
  of 
  a 
  ridge, 
  of 
  which 
  Dollar 
  Law, 
  2680, 
  

   Cramalt 
  Craig, 
  2723, 
  Dun 
  Law, 
  2584, 
  are 
  the 
  chief 
  minor 
  summits. 
  

   A 
  valley 
  curves 
  across 
  the 
  chain 
  from 
  Tweed 
  to 
  Yarrow, 
  its 
  highest 
  

   point 
  at 
  the 
  watershed 
  between 
  Talla 
  and 
  Megget 
  being 
  about 
  

   1440 
  ft. 
  : 
  the 
  Broad 
  Law 
  is 
  thus 
  separated 
  from 
  another 
  mass 
  of 
  

   hills 
  whose 
  heights 
  are, 
  Whitecoomb 
  2695, 
  Loch 
  Craig 
  2625, 
  

   Frithy 
  Brig 
  Head 
  2616, 
  Moll's 
  Cleuch 
  Dod 
  2571, 
  and 
  Great 
  Hill 
  

   2540. 
  A 
  second 
  depression 
  between 
  the 
  tributaries 
  of 
  Tweed 
  and 
  

   Moffat 
  water 
  separates 
  this 
  group 
  from 
  a 
  mass 
  culminating 
  in 
  

   Hartfell, 
  2650 
  ft. 
  The 
  extent 
  of 
  country, 
  over 
  2500 
  ft. 
  above 
  the 
  sea, 
  

   represented 
  by 
  these 
  heights 
  is 
  very 
  considerable, 
  for 
  the 
  hills 
  are 
  

   mostly 
  broad 
  low-backed 
  ridges 
  with 
  long 
  gentle 
  slopes 
  : 
  none 
  are 
  

   peaked. 
  Hence, 
  as 
  seen 
  from 
  the 
  top 
  of 
  the 
  Broad 
  Law, 
  they 
  appear 
  

   to 
  form 
  an 
  elevated 
  table-land 
  from 
  which 
  the 
  bosses 
  just 
  named 
  

   project 
  like 
  roches 
  moutonnees. 
  Armstrong 
  justly 
  remarks 
  that 
  a 
  

   race-course 
  of 
  more 
  than 
  two 
  miles 
  could 
  be 
  easily 
  made 
  on 
  the 
  

   summit 
  of 
  the 
  Broad 
  Law. 
  

  

  This 
  wide 
  plateau 
  and 
  these 
  long 
  slopes 
  would 
  under 
  other 
  

   climatal 
  conditions 
  form 
  an 
  extensive 
  snow-field 
  whence 
  glaciers 
  

   might 
  descend 
  into 
  the 
  valleys 
  beneath. 
  The 
  presence 
  of 
  moraines 
  

   in 
  twelve 
  valleys 
  demonstrates 
  the 
  former 
  existence 
  of 
  these 
  con- 
  

   ditions 
  ; 
  while 
  the 
  occurrence 
  of 
  boulder-clay 
  in 
  every 
  respect 
  com- 
  

   parable 
  with 
  that 
  of 
  the 
  low 
  country, 
  either 
  filling 
  up 
  valleys 
  

  

  * 
  Edin. 
  New 
  Phil. 
  Journal, 
  New 
  Series, 
  vol. 
  ii. 
  p. 
  184. 
  

  

  t 
  Transactions 
  of 
  Geological 
  Society 
  of 
  Glasgow, 
  toI. 
  i. 
  part 
  2. 
  Glasgow, 
  186^3. 
  

  

  