﻿GEOLOGICAL 
  CLIMATES 
  — 
  SCOTT 
  273 
  

  

  Blanford 
  reported 
  Permian 
  glaciation 
  from 
  peninsular 
  India 
  — 
  an 
  

   announcement 
  which 
  was 
  received 
  with 
  complete 
  skepticism 
  on 
  the 
  

   part 
  of 
  most 
  European 
  geologists, 
  though 
  followed 
  by 
  similar 
  reports 
  

   from 
  South 
  Africa, 
  Australia, 
  Brazil, 
  and 
  Germany. 
  In 
  1905 
  I 
  

   had 
  the 
  privilege 
  of 
  taking 
  several 
  geological 
  excursions 
  in 
  South 
  

   Africa, 
  which 
  had 
  been 
  arranged 
  for 
  the 
  meeting 
  of 
  the 
  British 
  

   Association 
  for 
  the 
  Advancement 
  of 
  Science, 
  under 
  the 
  direction 
  of 
  

   Mr. 
  A. 
  W. 
  Rogers, 
  chief 
  geologist 
  of 
  Cape 
  Colony, 
  and 
  of 
  Messrs. 
  

   Hall 
  and 
  Kynaston 
  in 
  the 
  Transvaal. 
  

  

  One 
  object 
  which 
  was 
  of 
  especial 
  interest 
  and 
  importance 
  to 
  all 
  

   of 
  the 
  visitors 
  at 
  that 
  time 
  was 
  an 
  examination 
  of 
  the 
  evidence 
  for 
  

   the 
  great 
  Permian 
  ice 
  cap, 
  and 
  the 
  geological 
  party 
  contained 
  such 
  

   eminent 
  students 
  of 
  glaciers 
  as 
  Professors 
  Penck 
  of 
  Berlin, 
  SoUas 
  

   of 
  Oxford, 
  Coleman 
  of 
  Toronto, 
  and 
  Davis 
  of 
  Harvard. 
  The 
  dis- 
  

   tinguished 
  Swedish 
  geologist. 
  Professor 
  Sjogren, 
  who 
  was 
  also 
  of 
  

   the 
  party, 
  told 
  me 
  that 
  few 
  continental 
  geologists 
  were 
  prepared 
  to 
  

   accept 
  the 
  hypothesis 
  of 
  Permian 
  glaciation. 
  Yet 
  the 
  field 
  demon- 
  

   strations 
  given 
  us, 
  especially 
  at 
  Riverton, 
  on 
  the 
  Vaal 
  River 
  below 
  

   Kimberley, 
  were 
  convincing 
  to 
  all 
  of 
  us, 
  without 
  exception. 
  The 
  

   bowlder 
  clays 
  and 
  moraines 
  and 
  the 
  ice 
  pavements, 
  with 
  their 
  

   characteristic 
  polishing 
  and 
  striation, 
  their 
  hummocks 
  aiid 
  roclies 
  

   moutonnees^ 
  were 
  every 
  whit 
  as 
  complete 
  evidence 
  of 
  glaciation 
  as 
  

   were 
  the 
  corresponding 
  Pleistocene 
  phenomena 
  at 
  home, 
  and 
  of 
  

   precisely 
  the 
  same 
  nature. 
  

  

  But 
  even 
  the 
  Permian 
  (or 
  " 
  Permo-Carboniferous," 
  as 
  the 
  English 
  

   geologists 
  prefer 
  to 
  call 
  it) 
  glaciation 
  was 
  not 
  the 
  only 
  ice 
  age 
  of 
  

   long 
  past 
  epochs. 
  There 
  is 
  evidence, 
  as 
  yet 
  incomplete, 
  of 
  glaciation 
  

   in 
  the 
  Carboniferous 
  of 
  North 
  America. 
  The 
  Bokkeveld 
  of 
  South 
  

   Africa, 
  a 
  marine 
  Devonian 
  formation, 
  contains 
  large, 
  faceted, 
  

   polished, 
  and 
  striated 
  pebbles 
  and 
  cobbles 
  of 
  unmistakable 
  glacial 
  

   origin, 
  but 
  ice 
  pavements 
  and 
  bovv'lder 
  clays 
  of 
  this 
  period 
  have 
  not 
  

   yet 
  been 
  found. 
  The 
  Silurian 
  moraines 
  of 
  Norway 
  were 
  probably 
  of 
  

   local 
  origin 
  and 
  do 
  not 
  indicate 
  any 
  widespread 
  climatic 
  changes. 
  

  

  Very 
  extensive 
  bowlder 
  beds, 
  observed 
  in 
  China 
  and 
  Australia 
  and 
  

   originally 
  referred 
  to 
  the 
  Cambrian, 
  are 
  now 
  placed 
  in 
  the 
  later 
  pre- 
  

   Cambrian 
  eras, 
  while 
  the 
  tillites 
  described 
  by 
  Professor 
  Coleman 
  in 
  

   Ontario 
  and 
  those 
  of 
  British 
  Bechuanaland 
  in 
  Africa 
  are 
  of 
  a 
  still 
  

   more 
  ancient 
  date. 
  Thus 
  Ave 
  have 
  the 
  remarkable 
  fact 
  that 
  glacia- 
  

   tion 
  on 
  a 
  continental 
  scale 
  has 
  repeatedly 
  occurred, 
  not 
  less 
  than 
  fivt 
  

   times 
  and 
  perhaps 
  more, 
  in 
  the 
  recorded 
  history 
  of 
  the 
  earth. 
  These 
  

   recurrent 
  climatic 
  phenomena 
  can 
  not 
  be 
  called 
  rhythmical 
  because, 
  

   so 
  far 
  as 
  we 
  can 
  judge, 
  the 
  intervals 
  between 
  them 
  were 
  not 
  of 
  

   similar 
  length, 
  features 
  which 
  render 
  the 
  problem 
  of 
  causation 
  all 
  

   the 
  more 
  complex 
  and 
  difficult. 
  

  

  