﻿AGE 
  OF 
  THE 
  EARTH 
  — 
  CHAMBERLIN 
  AND 
  OTHERS. 
  255 
  

  

  of 
  sodium 
  in 
  average 
  igneous 
  rock 
  is 
  about 
  thirty 
  times 
  as 
  great 
  as 
  

   their 
  content 
  of 
  chlorine. 
  This 
  is 
  a 
  large 
  difference, 
  but 
  it 
  does 
  

   not 
  represent 
  the 
  full 
  discrepancy, 
  for 
  the 
  chlorine 
  in 
  the 
  ocean 
  

   exceeds 
  the 
  sodium 
  in 
  about 
  the 
  proportion 
  of 
  1.8 
  to 
  1. 
  Taking 
  this 
  

   into 
  account, 
  the 
  discrepancy 
  rises 
  to 
  somewhat 
  above 
  50 
  to 
  1. 
  This 
  

   is 
  a 
  formidable 
  discrepancy. 
  How 
  is 
  it 
  to 
  be 
  met 
  on 
  the 
  assump- 
  

   tion 
  that 
  the 
  sodium 
  in 
  solution 
  is 
  not 
  reconverted 
  into 
  sodium 
  solids, 
  

   but 
  remains 
  in 
  perpetual 
  solution 
  ? 
  The 
  dilemma 
  is 
  not 
  much 
  relieved 
  

   by 
  reckoning 
  in 
  the 
  sediments 
  and 
  the 
  ocean 
  salts, 
  for 
  Clarke 
  and 
  

   Washington 
  also 
  give 
  18 
  the 
  ratio 
  of 
  sodium 
  to 
  chlorine 
  when 
  the 
  

   atmosphere 
  and 
  hydrosphere 
  are 
  reckoned 
  in 
  with 
  the 
  outer 
  10 
  

   miles 
  of 
  the 
  lithosphere. 
  The 
  discrepancy, 
  corrected 
  for 
  actual 
  

   oceanic 
  proportions, 
  is 
  even 
  then 
  nearly 
  20 
  to 
  1. 
  Quite 
  naturally 
  

   volcanoes 
  have 
  been 
  thought 
  to 
  be 
  a 
  source 
  of 
  excess 
  of 
  chlorine, 
  but 
  

   any 
  contribution 
  from 
  the 
  volcanoes 
  is 
  covered 
  by 
  this 
  inclusion 
  

   of 
  the 
  whole 
  atmosphere 
  and 
  hydrosphere 
  in 
  the 
  average. 
  Besides, 
  

   the 
  later 
  studies 
  of 
  volcanic 
  gases 
  do 
  not 
  sustain 
  the 
  earlier 
  views 
  that 
  

   they 
  contained 
  a 
  specially 
  high 
  content 
  of 
  chlorine. 
  19 
  The 
  observed 
  

   differences 
  between 
  the 
  sodium 
  and 
  the 
  chlorine 
  appear 
  to 
  have 
  

   grown 
  mainly 
  out 
  of 
  the 
  normal 
  processes 
  of 
  cyclic 
  change 
  when 
  

   these 
  are 
  viewed 
  in 
  their 
  largest 
  aspects. 
  If 
  the 
  sodium 
  returns 
  to 
  

   the 
  solid 
  state 
  in 
  due 
  (though 
  lesser) 
  proportion 
  to 
  the 
  potassium, 
  

   magnesium, 
  calcium, 
  and 
  chlorine, 
  as 
  these 
  constituents 
  are 
  found 
  

   mixed 
  in 
  the 
  solutes 
  and 
  the 
  sediments, 
  there 
  is 
  no 
  necessary 
  dis- 
  

   crepancy 
  in 
  these 
  great 
  differences. 
  The 
  discrepancy 
  is 
  constructive 
  

   and 
  is 
  imposed 
  by 
  the 
  assumption 
  that 
  the 
  sodium 
  does 
  not 
  take 
  its 
  

   proportional 
  part 
  in 
  cyclic 
  action. 
  Under 
  the 
  alternative 
  interpreta- 
  

   tion, 
  the 
  amounts 
  of 
  the 
  several 
  elements 
  present 
  in 
  the 
  ocean 
  are 
  

   primarily 
  functions 
  of 
  their 
  own 
  cyclic 
  histories; 
  their 
  proportions 
  

   are 
  not 
  predetermined 
  solely 
  by 
  the 
  composition 
  of 
  the 
  igneous 
  rocks 
  

   now 
  at 
  the 
  surface, 
  but 
  rather 
  by 
  the 
  relations 
  of 
  their 
  own 
  solvent 
  

   to 
  their 
  non-solvent 
  natures 
  under 
  the 
  conditions 
  of 
  their 
  long 
  com- 
  

   plex 
  history. 
  Specifially, 
  in 
  the 
  case 
  of 
  sodium 
  and 
  chlorine, 
  the 
  

   observed 
  ratio 
  merely 
  means 
  that 
  the 
  solution 
  stages 
  of 
  sodium 
  com- 
  

   pared 
  with 
  its 
  solid 
  stages 
  are 
  much 
  inferior 
  to 
  those 
  of 
  chlorine, 
  just 
  

   as 
  those 
  of 
  potassium 
  are 
  much 
  inferior 
  to 
  those 
  of 
  sodium, 
  and 
  so 
  

   on 
  through 
  the 
  list. 
  But, 
  however 
  cogent 
  this 
  may 
  be, 
  definite 
  evi- 
  

   dence 
  that 
  sodium 
  does 
  enter 
  freely 
  into 
  the 
  cyclic 
  processes, 
  in 
  due 
  

   proportion 
  to 
  the 
  action 
  of 
  its 
  associates, 
  however 
  inferior 
  the 
  pro- 
  

   portion 
  may 
  be, 
  will 
  naturally 
  be 
  demanded. 
  Allusion 
  has 
  already 
  

   been 
  made 
  to 
  a 
  neglected 
  factor. 
  Let 
  us 
  turn 
  to 
  that. 
  

  

  18 
  Ibid., 
  p. 
  114. 
  

  

  10 
  E. 
  T. 
  Allen, 
  " 
  Chemical 
  aspects 
  of 
  vulcanism 
  with 
  a 
  collection 
  of 
  the 
  analyses 
  of 
  

   volcanic 
  gases." 
  Papers 
  from 
  the 
  Geophysical 
  Laboratory, 
  Carnegie 
  Institution 
  of 
  Wash- 
  

   ington, 
  No. 
  440 
  (1922), 
  pp. 
  1-80. 
  

  

  