﻿120 
  

  

  C. 
  CALLAWAY 
  ON 
  THE 
  PRECAMBEIAE 
  (aEOH^EAN) 
  

  

  trending 
  to 
  the 
  south-south-west, 
  which 
  are 
  generally 
  inconspicuous 
  

   owing 
  to 
  the 
  greater 
  height 
  of 
  the 
  parallel 
  ranges 
  of 
  the 
  Longmynd 
  

   and 
  the 
  Stiper 
  Stones 
  on 
  either 
  side 
  ; 
  but 
  Pontesford 
  Hill, 
  which 
  is 
  

   partly 
  Archaean, 
  projects 
  into 
  the 
  plain 
  surrounding 
  Shrewsbury 
  as 
  

   a 
  prominent 
  outlier 
  from 
  the 
  mountain 
  district 
  of 
  western 
  Shrop- 
  

   shire, 
  corresponding 
  geographically, 
  as 
  it 
  does 
  geologically, 
  to 
  the 
  

   Wrekin 
  in 
  the 
  eastern 
  chain. 
  The 
  position 
  and 
  relations 
  of 
  the 
  

   masses 
  of 
  Archaean 
  rock 
  exposed 
  along 
  the 
  axis 
  are 
  shown 
  in 
  the 
  

   accompanying 
  map. 
  Some 
  of 
  the 
  boundaries 
  are 
  necessarily 
  approxi- 
  

   mations. 
  

  

  Sketch 
  Map 
  of 
  the 
  Western 
  Archaean 
  axis 
  of 
  Shropshire. 
  

   (Scale, 
  ± 
  inch 
  to 
  a 
  mile.) 
  

  

  ft 
  

  

  

  Microscopic 
  notes 
  on 
  some 
  of 
  the 
  principal 
  rock 
  types 
  are 
  kindly 
  

   furnished 
  by 
  Prof. 
  Bonney, 
  F.R.S. 
  It 
  is 
  very 
  satisfactory 
  to 
  be 
  able 
  

   to 
  state 
  that 
  his 
  conclusions, 
  formed 
  upon 
  slides 
  alone, 
  agree 
  precisely 
  

   with 
  my 
  field-determinations. 
  

  

  b. 
  Detailed 
  Geology 
  of 
  the 
  Axis. 
  

   1*. 
  Pontesford 
  Hill. 
  — 
  This 
  elevation 
  is 
  about 
  one 
  mile 
  in 
  length 
  

   * 
  This 
  and 
  the 
  following 
  numbers 
  (1-7) 
  correspond 
  to 
  the 
  numbers 
  in 
  the 
  map. 
  

  

  