﻿$6 
  PROCEEDINGS 
  OF 
  THE 
  GEOLOGICAL 
  SOCIETY. 
  

  

  the 
  case, 
  by 
  no 
  means 
  rigorously 
  denned, 
  as 
  it 
  was 
  impossible 
  to 
  

   say 
  what 
  was 
  the 
  relation 
  in 
  magnitude 
  between, 
  for 
  instance, 
  

   an 
  epoch 
  and 
  a 
  period; 
  and 
  although 
  no 
  difficulty 
  was 
  found 
  in 
  

   the 
  division 
  of 
  all 
  sedimentary 
  rocks 
  into 
  great 
  groups, 
  and 
  of 
  

   geological 
  time 
  into 
  great 
  eras, 
  the 
  case 
  was 
  different 
  when 
  an 
  

   attempt 
  was 
  made 
  to 
  divide 
  the 
  Palaeozoic, 
  Mesozoic, 
  and 
  Caenozoic 
  

   groups 
  or 
  eras 
  into 
  systems 
  or 
  periods 
  and 
  series. 
  This 
  took 
  place 
  

   at 
  a 
  subsequent 
  stage. 
  

  

  As 
  in 
  Paris, 
  so 
  in 
  Bologna, 
  the 
  consideration 
  of 
  the 
  further 
  steps 
  

   to 
  be 
  taken 
  towards 
  the 
  establishment 
  of 
  uniformity 
  in 
  geological 
  

   nomenclature 
  was 
  entrusted 
  to 
  a 
  Committee 
  composed, 
  on 
  this 
  

   occasion, 
  of 
  17 
  members, 
  each 
  representing 
  a 
  separate 
  country. 
  

   Meetings 
  of 
  this 
  Committee, 
  and 
  of 
  that 
  for 
  the 
  geological 
  map 
  

   of 
  Europe, 
  were 
  held 
  together 
  in 
  September 
  1882 
  at 
  Poix 
  in 
  

   the 
  Pyrenees, 
  and 
  in 
  August 
  1883 
  at 
  Zurich 
  in 
  Switzerland. 
  Both 
  

   meetings, 
  considering 
  that 
  the 
  members 
  of 
  the 
  Committees 
  came 
  for 
  

   the 
  most 
  part 
  from 
  distant 
  parts 
  of 
  Europe, 
  were 
  well 
  attended. 
  

   Of 
  the 
  17 
  members 
  of 
  the 
  Nomenclature 
  Committee, 
  8 
  attended 
  at 
  

   Poix 
  and 
  9 
  at 
  Zurich 
  ; 
  whilst 
  of 
  8 
  members 
  of 
  the 
  Committee 
  for 
  

   the 
  preparation 
  of 
  a 
  geological 
  map 
  of 
  Europe, 
  5 
  were 
  present 
  on 
  

   each 
  occasion 
  and 
  took 
  part 
  in 
  the 
  discussions 
  on 
  nomenclature. 
  

   These 
  were 
  mainly 
  devoted 
  to 
  a 
  classification 
  of 
  sedimentary 
  and 
  

   igneous 
  rocks 
  to 
  be 
  recommended 
  to 
  the 
  Geological 
  Congress 
  of 
  

   Berlin 
  for 
  adoption 
  in 
  the 
  geological 
  map 
  of 
  Europe. 
  Questions 
  

   relating 
  to 
  the 
  coloration 
  of 
  the 
  map 
  were 
  discussed 
  by 
  the 
  Map 
  

   Committee 
  sitting 
  by 
  itself. 
  Thus 
  the 
  whole 
  question 
  of 
  unification, 
  

   both 
  of 
  maps 
  and 
  of 
  nomenclature 
  proper, 
  between 
  the 
  Bologna 
  

   Congress 
  of 
  1881 
  and 
  the 
  Berlin 
  Congress 
  of 
  1885 
  (and 
  I 
  think 
  

   more 
  real 
  progress 
  was 
  made 
  during 
  this 
  period 
  than 
  either 
  before 
  

   or 
  after) 
  was 
  mainly 
  limited 
  to 
  a 
  thoroughly 
  practical 
  undertaking 
  

   — 
  the 
  general 
  classification 
  of 
  rocks, 
  and 
  the 
  general 
  system 
  of 
  

   coloration 
  for 
  adoption 
  in 
  the 
  geological 
  map 
  of 
  Europe. 
  But 
  

   although 
  there 
  were 
  many 
  advantages 
  attending 
  the 
  practical 
  form 
  

   that 
  the 
  question 
  of 
  unification 
  had 
  taken, 
  there 
  was 
  a 
  serious 
  

   disadvantage 
  in 
  the 
  limitation 
  of 
  the 
  discussion 
  to 
  Europe 
  ; 
  and, 
  in 
  

   fact, 
  this 
  change 
  involved 
  a 
  complete 
  departure, 
  unless 
  I 
  am 
  much 
  

   mistaken, 
  from 
  the 
  intentions 
  of 
  the 
  geologists 
  by 
  whom 
  the 
  

   original 
  scheme 
  of 
  a 
  congress 
  was 
  proposed. 
  

  

  A 
  scheme 
  of 
  classification 
  in 
  groups, 
  systems, 
  and 
  series 
  was 
  

   drawn 
  up 
  by 
  a 
  Committee 
  of 
  German 
  geologists 
  and 
  submitted 
  

   to 
  the 
  International 
  Committee 
  for 
  approval. 
  It 
  may 
  be 
  useful 
  to 
  

  

  