﻿Vol. 
  53.] 
  AJTCTIVERSARY 
  ADDRESS 
  OP 
  THE 
  PRESIDENT. 
  lxXXV 
  

  

  Peach 
  & 
  Home, 
  Q. 
  J". 
  G. 
  S. 
  vol. 
  xliv. 
  1888; 
  and 
  the 
  Eeports 
  of 
  

   the 
  Geological 
  Survey. 
  

  

  In 
  the 
  papers 
  by 
  Mr. 
  T. 
  Davies, 
  Prof. 
  Bonney, 
  Dr. 
  Callaway, 
  and 
  

   myself 
  petrological 
  descriptions 
  of 
  the 
  characteristic 
  rocks 
  fonnd 
  in 
  

   the 
  neighbourhoods 
  of 
  Gairloch, 
  Loch 
  Maree, 
  Central 
  and 
  Southern 
  

   Koss-shire, 
  and 
  a 
  portion 
  of 
  the 
  Central 
  Highlands 
  were 
  given. 
  

   Prof. 
  Bonney 
  showed 
  that 
  the 
  so-called 
  'syenite' 
  in 
  Glen 
  Logan 
  

   was 
  not 
  an 
  intrusive 
  mass, 
  but 
  a 
  portion 
  of 
  the 
  old 
  gneiss 
  

   floor 
  which 
  had 
  been 
  brought 
  into 
  that 
  position 
  by 
  faults, 
  and 
  I 
  

   pointed 
  out 
  that 
  the 
  older 
  gneisses 
  cropped 
  up 
  in 
  several 
  areas 
  east 
  

   of 
  Loch 
  Maree, 
  where 
  previously 
  they 
  had 
  been 
  unsuspected, 
  and 
  

   also 
  that 
  the 
  schistose 
  series 
  in 
  the 
  neighbourhood 
  of 
  Gairloch 
  was 
  

   unlike 
  any 
  which 
  had 
  previously 
  been 
  described 
  from 
  the 
  western 
  

   areas. 
  It 
  was 
  further 
  shown 
  that 
  at 
  the 
  base 
  of 
  the 
  Torridon 
  

   sandstone 
  large 
  masses 
  of 
  these 
  schists 
  occurred 
  in 
  association 
  with 
  

   fragments 
  derived 
  from 
  the 
  so-called 
  Lewisian 
  gneiss 
  and 
  numerous 
  

   other 
  fragments 
  which 
  could 
  not 
  then 
  be 
  located 
  in 
  the 
  district. 
  

   Attention 
  was 
  also 
  called 
  to 
  the 
  highly-faulted 
  condition 
  of 
  the 
  

   rocks 
  in 
  the 
  several 
  areas 
  examined, 
  and 
  the 
  newer 
  rocks 
  were 
  

   stated 
  to 
  occur 
  in 
  broken 
  synclinal 
  folds. 
  

  

  In 
  the 
  year 
  1883 
  Prof. 
  Lapworth, 
  when 
  describing 
  the 
  Durness 
  

   and 
  Eriboll 
  areas, 
  pointed 
  to 
  evidences 
  in 
  that 
  area 
  of 
  an 
  old 
  moun- 
  

   tain 
  system 
  accompanied 
  by 
  great 
  dislocations. 
  He 
  'also 
  divided 
  

   the 
  Palseozoic 
  rocks 
  of 
  those 
  areas 
  into 
  numerous 
  fossil 
  zones. 
  

   Moreover, 
  Dr. 
  Callaway, 
  in 
  the 
  same 
  year, 
  showed 
  that 
  there 
  were 
  

   evidences 
  of 
  great 
  dislocations 
  and 
  of 
  foldings 
  of 
  the 
  limestone- 
  and 
  

   quartzite-beds, 
  not 
  only 
  at 
  Durness 
  but 
  also 
  in 
  the 
  neighbourhood 
  

   of 
  Assynt. 
  He 
  had 
  previously, 
  in 
  a 
  paper 
  communicated 
  to 
  the 
  

   Geological 
  Society 
  in 
  1881, 
  stated 
  that 
  he 
  had 
  arrived 
  at 
  the 
  con- 
  

   clusion 
  that 
  the 
  sections 
  in 
  those 
  areas 
  ' 
  were 
  broken, 
  and 
  therefore 
  

   untrustworthy, 
  but 
  that 
  the 
  relations 
  of 
  the 
  several 
  rock-groups 
  

   were 
  inconsistent 
  with 
  the 
  supposition 
  that 
  the 
  limestone 
  passed 
  

   below 
  any 
  part 
  of 
  the 
  newer 
  metamorphic 
  series.' 
  1 
  

  

  In 
  the 
  year 
  1884 
  the 
  Director-General 
  of 
  the 
  Geological 
  Survey 
  

   (Sir 
  A. 
  Geikie) 
  and 
  Messrs. 
  Peach 
  & 
  Home, 
  in 
  a 
  paper 
  in 
  'Nature,' 
  

   November 
  13th 
  (vol. 
  xxxi. 
  p. 
  32), 
  stated 
  that 
  the 
  results 
  recently 
  

   obtained 
  by 
  them 
  when 
  re-surveying 
  the 
  Durness 
  and 
  Eriboll 
  areas 
  

   went 
  to 
  show 
  that 
  ' 
  the 
  Silurian 
  strata 
  in 
  the 
  Durness 
  area 
  are 
  

   arranged 
  in 
  the 
  form 
  of 
  a 
  basin 
  truncated 
  on 
  the 
  east 
  side 
  by 
  a 
  

   fault 
  that 
  brings 
  them 
  against 
  the 
  Archsean 
  gneiss.' 
  They 
  also 
  refer 
  

   to 
  the 
  flexures 
  and 
  great 
  dislocations 
  of 
  the 
  strata 
  in 
  the 
  Eriboll 
  

   area, 
  previously 
  pointed 
  out 
  by 
  Prof. 
  Lapworth, 
  and 
  Sir 
  A. 
  Geikie 
  

   1 
  Quart. 
  Journ. 
  Geol. 
  Soc. 
  vol. 
  xxxvii. 
  p. 
  239. 
  

  

  