﻿AGE 
  OF 
  THE 
  EARTH 
  — 
  CHAMBERLIN 
  AND 
  OTHERS. 
  261 
  

  

  3. 
  The 
  science 
  of 
  hydrogeology, 
  of 
  which 
  oceanology 
  is 
  only 
  a 
  

   part, 
  is 
  not 
  yet 
  ready 
  to 
  render 
  a 
  verdict 
  ; 
  it 
  has 
  more 
  need 
  of 
  a 
  court 
  

   of 
  inquiry 
  than 
  a 
  place 
  on 
  the 
  witness 
  stand. 
  

  

  THE 
  AGE 
  OF 
  THE 
  EARTH 
  FROM 
  THE 
  PALEONTOLOGICAL 
  VIEWPOINT. 
  

  

  By 
  John 
  M. 
  Clarke. 
  

  

  It 
  falls 
  to 
  me 
  to 
  consider 
  this 
  knotty 
  problem 
  on 
  the 
  basis 
  of 
  the 
  

   biological 
  evidence 
  alone, 
  in 
  so 
  far 
  as 
  it 
  is 
  possible 
  to 
  disentangle 
  this 
  

   from 
  its 
  almost 
  inevitable 
  complication 
  with 
  geological 
  accompani- 
  

   ments. 
  In 
  saying 
  biological 
  I 
  mean, 
  of 
  course, 
  biology 
  with 
  the 
  time 
  

   element 
  generously 
  admitted 
  ; 
  that 
  is, 
  not 
  the 
  biology 
  of 
  the 
  instant, 
  

   the 
  present, 
  but 
  the 
  long 
  biological 
  panorama 
  leading 
  up 
  to 
  the 
  

   present. 
  Thus 
  I 
  am 
  in 
  a 
  different 
  case 
  to 
  some 
  of 
  my 
  colleagues, 
  for 
  

   I 
  presume 
  it 
  safe 
  to 
  say 
  that 
  life 
  can 
  have 
  come 
  into 
  being 
  only 
  as 
  

   a 
  secondary 
  potency 
  in 
  the 
  evolution 
  of 
  force. 
  Just 
  what 
  I 
  mean 
  is 
  

   that 
  the 
  combination 
  or 
  interaction 
  of 
  physical 
  energies 
  of 
  different 
  

   categories 
  did 
  not 
  produce 
  the 
  form 
  of 
  energy 
  we 
  designate 
  as 
  life 
  

   till 
  after 
  a 
  very 
  long 
  chapter 
  of 
  the 
  earth's 
  planetary 
  history 
  had 
  been 
  

   written. 
  I 
  may 
  as 
  well 
  frankly 
  say 
  at 
  the 
  beginning 
  that 
  there 
  can 
  

   be 
  little 
  hope 
  of 
  arriving 
  either 
  at 
  a 
  reliable 
  or 
  an 
  approximate 
  con- 
  

   clusion 
  as 
  to 
  the 
  age 
  of 
  the 
  earth 
  through 
  this 
  paleontological 
  chan- 
  

   nel, 
  unless 
  the 
  study 
  of 
  the 
  chronological 
  development 
  of 
  life 
  may 
  in 
  

   some 
  way 
  afford 
  a 
  measure 
  of 
  the 
  rate 
  of 
  vital 
  processes 
  and 
  thus 
  the 
  

   measure 
  of 
  some 
  short 
  span 
  or 
  infinitesimal 
  fraction 
  of 
  earth 
  history. 
  

   This 
  is 
  a 
  shadowy 
  road 
  and 
  this 
  presentation 
  must 
  resolve 
  itself 
  into 
  

   consideration 
  of 
  such 
  evidences 
  as 
  there 
  may 
  be 
  for 
  time-requisites 
  

   in 
  the 
  consummation 
  of 
  evolutionary 
  biological 
  procedures, 
  whether 
  

   in 
  gross 
  or 
  in 
  detail. 
  The 
  bare 
  statement 
  of 
  this 
  fact 
  in 
  such 
  vague 
  

   form 
  must 
  carry 
  with 
  it 
  an 
  indication 
  of 
  the 
  grave 
  uncertainty 
  of 
  

   the 
  results 
  except 
  to 
  minds 
  of 
  the 
  fourth 
  dimension. 
  I 
  am 
  not 
  con- 
  

   vinced 
  that 
  it 
  is 
  within 
  the 
  power, 
  now 
  or 
  ever, 
  of 
  even 
  the 
  most 
  

   refined 
  understanding 
  of 
  paleontology, 
  to 
  accomplish 
  this 
  and 
  es- 
  

   tablish 
  such 
  standards 
  of 
  measurements. 
  Nor 
  am 
  I 
  at 
  all 
  confident 
  

   that 
  the 
  attempts 
  which 
  have 
  been 
  made 
  to 
  establish 
  such 
  rates 
  of 
  

   procedure 
  could 
  justify 
  the 
  great 
  labor 
  they 
  have 
  exacted, 
  were 
  it 
  

   not 
  for 
  the 
  important 
  accessory 
  facts 
  they 
  have 
  elicited. 
  

  

  There 
  seems 
  to 
  be 
  no 
  effective 
  reason 
  or 
  very 
  good 
  philosophy 
  in 
  

   declaring, 
  as 
  some 
  of 
  our 
  writers 
  have 
  been 
  wont 
  to 
  do, 
  that 
  all 
  life 
  

   is 
  one 
  life. 
  We 
  seem 
  to 
  have 
  really 
  established 
  the 
  polyphylogeny 
  of 
  

   several 
  races 
  not 
  only 
  in 
  the 
  lower 
  phyla 
  of 
  animals 
  and 
  plants, 
  but 
  

   among 
  the 
  vertebrates, 
  and 
  in 
  the 
  thought 
  of 
  competent 
  authority, 
  

   even 
  to 
  the 
  inclusion 
  of 
  man, 
  and 
  we 
  assign 
  these 
  like 
  products 
  to 
  a 
  

   differently 
  governed 
  and 
  directed 
  inheritance 
  emanating 
  from 
  fixed 
  

  

  55379—24 
  18 
  

  

  