﻿450 
  J. 
  E. 
  CAMPBELL 
  ON 
  POLAR 
  GLACIATION 
  ETC. 
  

  

  35. 
  About 
  Polar 
  Glactation 
  fyc. 
  By 
  J. 
  F. 
  Campbell, 
  Esq., 
  F.G.S. 
  

   (Bead 
  April 
  15, 
  1874.) 
  

  

  Introduction. 
  

  

  In 
  order 
  to 
  be 
  concise 
  and 
  comprehensible, 
  and 
  to 
  assign 
  a 
  

   reason 
  for 
  venturing 
  to 
  address 
  this 
  Society 
  upon 
  so 
  large 
  a 
  theme, 
  

   I 
  must 
  refer 
  to 
  former 
  work. 
  In 
  1865 
  and 
  1867 
  I 
  published 
  

   and 
  enlarged 
  a 
  book 
  called 
  ' 
  Frost 
  and 
  Fire.' 
  In 
  it 
  I 
  aimed 
  at 
  

   showing, 
  by 
  description 
  and 
  by 
  designs, 
  that 
  certain 
  forms 
  are 
  as 
  

   letters 
  inscribed 
  on 
  the 
  outside 
  of 
  the 
  globe 
  to 
  record 
  part 
  of 
  its 
  

   history. 
  

  

  Example. 
  A 
  volcanic 
  crater 
  and 
  a 
  water-course 
  differ 
  in 
  form, 
  

   as 
  do 
  the 
  letters 
  0, 
  S, 
  A. 
  Both 
  sets 
  of 
  forms 
  convey 
  meaning 
  to 
  

   those 
  who 
  have 
  learned 
  to 
  read. 
  A 
  record 
  of 
  volcanic 
  action 
  is 
  

   written 
  on 
  the 
  moon 
  in 
  black 
  and 
  white, 
  and 
  can 
  be 
  read 
  by 
  any 
  

   one 
  who 
  has 
  seen 
  Naples 
  and 
  its 
  volcanoes, 
  old 
  and 
  new. 
  In 
  

   November 
  1873 
  no 
  record 
  of 
  aqueous 
  or 
  other 
  " 
  denudation 
  " 
  had 
  

   been 
  written 
  upon 
  the 
  upper 
  cone 
  of 
  Vesuvius, 
  whose 
  igneous 
  

   outside 
  form 
  was 
  remade 
  in 
  1872, 
  and 
  grew 
  upon 
  the 
  older 
  

   mountain-top 
  after 
  1842. 
  But 
  a 
  deep 
  inscription 
  is 
  scored 
  in 
  water- 
  

   courses 
  and 
  deltas 
  within 
  and 
  without 
  the 
  cone 
  and 
  crater 
  of 
  Monte 
  

   Nuovo, 
  which 
  grew 
  in 
  1538, 
  during 
  one 
  scattering 
  discharge 
  of 
  a 
  

   fountain 
  of 
  hot 
  vapours, 
  fluids, 
  and 
  solids. 
  That 
  particular 
  gun 
  

   has 
  not 
  fired 
  since. 
  A 
  deeper 
  "water-mark" 
  is 
  on 
  the 
  older 
  

   " 
  Astroni," 
  which 
  was 
  a 
  volcano, 
  and 
  now 
  is 
  a 
  wooded 
  preserve 
  for 
  

   game, 
  and 
  upon 
  " 
  Somnia." 
  If 
  we 
  measure 
  the 
  relative 
  depth 
  of 
  

   these 
  water-marks 
  upon 
  two 
  volcanic 
  surfaces 
  newly 
  made 
  in 
  1872 
  

   and 
  in 
  1538, 
  a 
  scale 
  of 
  depth 
  may 
  be 
  constructed 
  by 
  which 
  to 
  

   estimate 
  the 
  age 
  of 
  Astroni 
  and 
  Somma, 
  by 
  " 
  denudation 
  " 
  of 
  their 
  

   igneous 
  surfaces. 
  No 
  such 
  water-marks 
  are 
  seen 
  upon 
  older 
  and 
  

   bigger 
  cones 
  and 
  craters 
  in 
  the 
  moon, 
  which 
  cannot 
  be 
  reached, 
  

   but 
  which 
  can 
  be 
  seen. 
  

  

  It 
  is 
  recorded 
  on 
  the 
  outside 
  of 
  these 
  two 
  worlds 
  by 
  certain 
  forms, 
  

   that 
  it 
  has 
  rained 
  little 
  since 
  1872 
  at 
  Naples, 
  that 
  it 
  has 
  rained 
  a 
  

   great 
  deal 
  there 
  since 
  1538, 
  that 
  it 
  has 
  rained 
  a 
  great 
  deal 
  more 
  

   there 
  since 
  the 
  unknown 
  date 
  of 
  the 
  last 
  eruption 
  of 
  Astroni 
  and 
  

   Somma. 
  There 
  is 
  no 
  record 
  of 
  glacial 
  denudation 
  at 
  Naples. 
  There 
  

   is 
  no 
  record 
  of 
  any 
  denudation 
  on 
  the 
  mountains 
  in 
  the 
  moon, 
  which 
  

   seems 
  to 
  have 
  no 
  atmosphere 
  and 
  no 
  clouds. 
  I 
  strove 
  to 
  learn 
  this 
  

   natural 
  alphabet 
  of 
  form 
  ; 
  I 
  copied 
  natural 
  forms, 
  and 
  gave 
  illus- 
  

   trations 
  ; 
  and 
  I 
  used 
  printers' 
  signs 
  as 
  symbols 
  to 
  convey 
  my 
  

   meaning 
  shortly. 
  In 
  the 
  book 
  quoted, 
  A 
  is 
  like 
  the 
  shape 
  of 
  

   mountain 
  peaks 
  ; 
  Y 
  or 
  V 
  the 
  section 
  of 
  a 
  water-course; 
  S, 
  windings 
  ; 
  

   A, 
  fan-shaped 
  deposits 
  of 
  drift, 
  washed 
  out 
  of 
  a 
  water-course 
  and 
  

   called 
  a 
  " 
  delta." 
  *-~s 
  expresses 
  the 
  rounded 
  outline 
  of 
  a 
  glaciated 
  

   hill 
  country 
  ; 
  ■^^ 
  hollows 
  made 
  or 
  widened 
  by 
  glacial 
  erosion. 
  

   Water-courses 
  of 
  all 
  sorts 
  and 
  sizes 
  are 
  alike, 
  and 
  record 
  the 
  same 
  

  

  