﻿BNDLicH.] 
  APPENDIX 
  ANCIENT 
  GLACIERS. 
  225 
  

  

  perature. 
  In 
  order 
  to 
  obtain 
  the 
  requisite 
  amount 
  of 
  moisture 
  for 
  

   the 
  regions 
  where 
  we 
  observe 
  evidence 
  of 
  ancient 
  glaciers, 
  we 
  must 
  

   necessarily 
  either 
  assume 
  that 
  at 
  the 
  time 
  of 
  their 
  existence 
  the 
  

   quantity 
  of 
  precipitated 
  moisture 
  was 
  greater, 
  or 
  that 
  the 
  mean 
  annual 
  

   temperature 
  was 
  lower, 
  than 
  it 
  is 
  at 
  present. 
  If 
  we 
  study 
  the 
  country 
  ad- 
  

   jacent 
  to 
  that 
  where 
  we 
  find 
  glacial 
  evidence, 
  we 
  will 
  observe 
  that 
  a 
  

   by 
  far 
  larger 
  area 
  was 
  at 
  one 
  time 
  covered 
  by 
  water 
  than 
  to-day. 
  The 
  

   Great 
  Salt 
  Lake 
  extended 
  beyond 
  the 
  boundaries 
  that 
  now 
  confine 
  it, 
  

   spreading 
  over 
  a 
  wide 
  expanse 
  of 
  country.* 
  Many 
  of 
  the 
  valleys 
  in 
  

   Arizona, 
  Nevada, 
  and 
  Southern 
  California, 
  that 
  now 
  present 
  nothing 
  but 
  

   the 
  sterile 
  sand 
  and 
  gravel 
  that 
  rapidly 
  destroy 
  the 
  few 
  streams 
  of 
  

   these 
  regions, 
  were 
  at 
  that 
  time 
  filled 
  with 
  lakes. 
  Here, 
  then, 
  we 
  have 
  

   a 
  source 
  of 
  moisture 
  far 
  exceeding, 
  in 
  quantity, 
  that 
  carried 
  eastward 
  

   at 
  present 
  by 
  the 
  prevailing 
  westerly 
  winds. 
  Near 
  the 
  western 
  coast, 
  

   where 
  precipitation 
  of 
  water 
  is 
  more 
  abundant 
  than 
  farther 
  inland, 
  we 
  

   find 
  glaciers 
  still 
  existing 
  in 
  some 
  of 
  the 
  ranges. 
  I 
  conclude, 
  there- 
  

   fore, 
  that 
  the 
  ancient 
  glaciers 
  of 
  Colorado 
  and 
  regions 
  similar 
  to 
  it, 
  both 
  

   as 
  regards 
  geographical 
  location 
  and 
  orographic 
  construction, 
  owe 
  

   their 
  former 
  existence 
  mainly 
  to 
  the 
  presence 
  of 
  those 
  numerous 
  sheets 
  

   of 
  water 
  farther 
  west. 
  These 
  now 
  have 
  disappeared, 
  and 
  incident 
  upon 
  

   their 
  removal, 
  whatever 
  may 
  have 
  produced 
  that, 
  was 
  the 
  recession 
  and 
  

   final 
  extinction 
  of 
  the 
  ancient 
  glaciers. 
  Holding 
  this 
  view, 
  I 
  maintain 
  that 
  

   the 
  lakes 
  formerly 
  filling 
  so 
  many 
  valleys 
  were 
  in 
  existence 
  before 
  any 
  gla- 
  

   ciers 
  occurred 
  in 
  the 
  Rocky 
  Mountains 
  proper. 
  Whether 
  these 
  lakes 
  were 
  

   prior, 
  synchronous, 
  or 
  subsequent 
  to 
  the 
  accepted 
  glacial 
  epoch 
  of 
  the 
  

   North 
  American 
  continent 
  is 
  of 
  no 
  importance 
  in 
  this 
  instance, 
  inasmuch 
  

   as 
  their 
  presence 
  at 
  any 
  given 
  time 
  would 
  have 
  produced 
  the 
  local 
  effects 
  

   of 
  glaciation 
  in 
  the 
  regions 
  under 
  discussion. 
  It 
  is 
  highly 
  probable, 
  

   however, 
  that 
  the 
  period 
  of 
  their 
  greatest 
  magnitude 
  fell 
  into 
  the 
  time 
  

   of 
  the 
  general 
  glacial 
  epoch, 
  and 
  thus^ 
  indirectly, 
  do 
  the 
  local 
  glaciers 
  

   observed 
  become 
  connected 
  therewith. 
  So 
  far 
  as 
  they 
  are 
  concerned 
  

   directly, 
  however, 
  I 
  claim 
  for 
  their 
  origin 
  immediate 
  telluric 
  causes 
  

   causes 
  that 
  were 
  originally 
  the 
  result, 
  perhaps, 
  of 
  cosmic 
  conditions 
  of 
  

   that 
  character 
  upon 
  which 
  CroU 
  bases 
  his 
  ingenious 
  and 
  acceptable 
  

   hypothesis. 
  An 
  analogous 
  case 
  to 
  the 
  one 
  under 
  consideration 
  is 
  that 
  

   regarding 
  the 
  former 
  and 
  present 
  glaciers 
  of 
  Switzerland. 
  Escher 
  von 
  

   der 
  Linth, 
  the 
  Swiss 
  geologist,! 
  supported 
  by 
  Desor, 
  has 
  explained 
  the 
  

   gradual 
  diminution 
  of 
  Swiss 
  glaciers 
  in 
  a 
  manner 
  that 
  would 
  fully 
  

   account 
  for 
  the 
  formation 
  as 
  well 
  as 
  for 
  the 
  disappearance 
  of 
  those 
  for- 
  

   merly 
  existing 
  in 
  the 
  Eocky 
  Mountains 
  and 
  the 
  Sierra 
  Nevada. 
  It 
  is 
  a 
  

   well-established 
  fact 
  that, 
  in 
  comparatively 
  recent 
  geological 
  ages, 
  the 
  

   desert 
  of 
  Sahara 
  was 
  in 
  connection 
  both 
  with 
  the 
  Mediterranean 
  Sea 
  

   and 
  the 
  Atlantic 
  Ocean. 
  It 
  was 
  then 
  essentially 
  an 
  inland 
  sea 
  of 
  enor- 
  

   mous 
  dimensions. 
  The 
  time 
  of 
  its 
  greatest 
  extent 
  may 
  be 
  assumed 
  to 
  

   have 
  been 
  synchronous 
  with 
  that 
  of 
  the 
  greatest 
  development 
  of 
  South 
  

   European 
  glaciers. 
  One 
  instance 
  may 
  suffice. 
  Proof 
  has 
  been 
  furnished 
  

   by 
  Captain 
  Bach| 
  that 
  at 
  one 
  time 
  the 
  glacier 
  of 
  the 
  Ehine 
  extended 
  

   northward 
  across 
  Lake 
  Constance, 
  far 
  into 
  the 
  present 
  kingdom 
  of 
  Wiir- 
  

   temberg. 
  This 
  was 
  by 
  no 
  means 
  the 
  case 
  at 
  so 
  very 
  remote 
  a 
  period, 
  as 
  

   the 
  archaeological 
  remains 
  found 
  at 
  Schusseuried 
  by 
  Professor 
  Fraas§ 
  

   tend 
  to 
  show. 
  The 
  glacier 
  of 
  the 
  Rhone 
  at 
  that 
  time 
  extended 
  southward 
  

  

  * 
  Report 
  Explorations 
  and 
  Surveys 
  West 
  of 
  the 
  One 
  Hundredth 
  Meridian, 
  1875, 
  p. 
  88. 
  

   tAllsemeine 
  Zeitung, 
  Bell., 
  No. 
  9 
  and 
  10, 
  1865. 
  

   \ 
  VVuertt. 
  Jahreshefte, 
  1869, 
  ii, 
  p. 
  113. 
  

   § 
  Arch, 
  flir 
  Anthrop., 
  torn, 
  ii, 
  1867. 
  

  

  15 
  G 
  S 
  

  

  