﻿330 
  

  

  T. 
  F. 
  JAMESON 
  ON 
  THE 
  LAST 
  STAGE 
  OF 
  

  

  Fig. 
  1.— 
  Terminal 
  slope 
  of 
  a 
  glacier, 
  with 
  gravelly 
  debris 
  resting 
  

   against 
  it. 
  

  

  Fig. 
  2. 
  — 
  Retreating 
  glacier, 
  leaving 
  a 
  Kami 
  or 
  Esker. 
  

  

  M. 
  Collomb 
  mentions 
  that 
  the 
  frontal 
  slope 
  of 
  terminal 
  moraines 
  

   is 
  generally 
  steeper 
  than 
  that 
  of 
  the 
  other 
  side. 
  In 
  the 
  old 
  moraines 
  

   of 
  the 
  Yosges 
  this 
  is 
  constantly 
  the 
  case, 
  the 
  frontal 
  slope 
  sometimes 
  

   amounting 
  to 
  an 
  angle 
  of 
  35°. 
  Sir 
  Richard 
  Griffith 
  tells 
  us 
  that 
  in 
  

   the 
  case 
  of 
  the 
  Irish 
  horseshoe 
  Eskers 
  one 
  side 
  generally 
  slopes 
  at 
  

   an 
  angle 
  of 
  30° 
  and 
  the 
  other 
  at 
  10° 
  to 
  15°. 
  

  

  If 
  the 
  Kaims 
  and 
  Eskers 
  were 
  formed 
  beneath 
  the 
  sea 
  by 
  con- 
  

   flicting 
  tides 
  and 
  currents, 
  how 
  comes 
  it 
  they 
  are 
  so 
  destitute 
  of 
  

   marine 
  fossils 
  ? 
  No 
  satisfactory 
  explanation 
  of 
  this 
  has 
  been 
  

   given. 
  As 
  most 
  of 
  the 
  Irish 
  ridges 
  are 
  composed 
  of 
  limestone 
  gravel, 
  

   there 
  would 
  be 
  the 
  less 
  likelihood 
  of 
  the 
  shells 
  being 
  dissolved 
  by 
  the 
  

   percolation 
  of 
  water. 
  The 
  only 
  shells 
  I 
  ever 
  found 
  in 
  a 
  Kaim 
  were 
  

   in 
  the 
  parish 
  of 
  Slains 
  in 
  Aberdeenshire. 
  These 
  were 
  old-Crag 
  shells 
  

   ( 
  Voluta 
  Lamberti 
  and 
  others), 
  showing, 
  as 
  I 
  conceive, 
  that 
  the 
  forma- 
  

   tion 
  of 
  the 
  Kaim 
  was 
  long 
  posterior 
  to 
  the 
  time 
  when 
  the 
  mollusca 
  

   lived 
  which 
  inhabited 
  the 
  shells, 
  and 
  therefore 
  affording 
  no 
  argument 
  

   that 
  the 
  ridge 
  owed 
  its 
  shape 
  to 
  the 
  action 
  of 
  the 
  sea. 
  The 
  occur- 
  

   rence 
  of 
  these 
  old 
  shells, 
  however, 
  was 
  so 
  far 
  interesting 
  as 
  it 
  showed 
  

   that, 
  if 
  the 
  gravel 
  of 
  other 
  Kaims 
  had 
  been 
  originally 
  fossiliferous, 
  

   the 
  shells 
  in 
  them 
  ought 
  not 
  to 
  have 
  all 
  disappeared. 
  The 
  marked 
  

   absence 
  of 
  marine 
  fossils 
  in 
  the 
  Kaims, 
  Eskers, 
  and 
  upper 
  drift 
  or 
  

   upper 
  boulder-clay 
  affords 
  a 
  strong 
  presumption 
  that 
  these 
  deposits 
  

   were 
  not 
  accumulated 
  beneath 
  the 
  sea. 
  

  

  I 
  have 
  also 
  a 
  difficulty 
  in 
  believing 
  that 
  narrow 
  crooked 
  (some- 
  

   times 
  even 
  zigzag) 
  ridges 
  of 
  gravel, 
  with 
  their 
  sides 
  sloping 
  at 
  angles 
  

   of 
  20° 
  to 
  30°, 
  would 
  be 
  formed 
  beneath 
  the 
  sea, 
  or 
  at 
  all 
  events 
  

   could 
  have 
  emerged 
  from 
  it 
  without 
  being 
  thrown 
  down. 
  I 
  should 
  

   think 
  the 
  materials 
  could 
  not 
  lie 
  at 
  such 
  an 
  angle 
  of 
  repose 
  beneath 
  

   agitated 
  water, 
  and 
  would 
  have 
  been 
  levelled 
  to 
  some 
  extent 
  as 
  they 
  

   came 
  under 
  the 
  influence 
  of 
  the 
  waves 
  and 
  breakers. 
  They 
  could 
  

   not 
  have 
  stood 
  the 
  dash 
  of 
  the 
  water 
  in 
  stormy 
  weather, 
  even 
  in 
  

  

  