﻿Radium- 
  Content 
  of 
  Sea 
  Water. 
  401 
  

  

  the 
  same 
  crucible 
  revealed 
  only 
  the 
  usual 
  trace 
  of 
  radium 
  in 
  

   the 
  carbonates 
  : 
  in 
  this 
  case 
  negligible. 
  

  

  This 
  treatment 
  was 
  then 
  applied 
  to 
  many 
  of 
  the 
  sea 
  waters 
  

   \vhere 
  any 
  haziness 
  appeared 
  to 
  have 
  developed. 
  It 
  wdll 
  be 
  

   noticed 
  that 
  an 
  increase 
  in 
  the 
  evolution 
  o£ 
  emanation 
  has 
  

   not 
  always 
  occurred. 
  But 
  in 
  one 
  other 
  case, 
  in 
  which 
  the 
  

   haziness 
  was 
  considerable, 
  there 
  was 
  a 
  very 
  marked 
  increase 
  

   observed 
  (17). 
  The 
  suspension 
  from 
  the 
  Atlantic 
  water 
  (11) 
  

   was 
  tested 
  separately 
  for 
  radium, 
  and 
  the 
  filtered 
  water 
  also 
  

   independently 
  dealt 
  with. 
  The 
  quantity 
  in 
  column 
  III. 
  is 
  from 
  

   the 
  added 
  results 
  of 
  these 
  tests. 
  About 
  one-third 
  of 
  the 
  

   quantity 
  of 
  radium 
  contributing 
  to 
  the 
  final 
  result 
  was 
  found 
  

   in 
  the 
  suspension. 
  More 
  particularly 
  : 
  the 
  water 
  in 
  its 
  final 
  

   reading 
  showed 
  18'9 
  x 
  10"^^ 
  gram 
  radium 
  and 
  the 
  whole 
  of 
  

   the 
  separated 
  suspension 
  ]0-7 
  x 
  10~^^. 
  

  

  If 
  my 
  interpretation 
  of 
  these 
  experiments 
  is 
  correct 
  it 
  

   would 
  appear 
  that 
  in 
  some 
  cases, 
  where 
  much 
  organic 
  matter 
  

   is 
  present,, 
  the 
  emanation 
  may 
  be 
  retained 
  to 
  a 
  considerable 
  

   extent 
  even 
  after 
  prolonged 
  boihng. 
  I 
  can 
  off'er 
  no 
  opinion 
  

   as 
  to 
  the 
  ultimate 
  origin 
  of 
  the 
  effect 
  observed 
  : 
  whether 
  it 
  

   arises 
  owing 
  to 
  conditions 
  of 
  decay 
  of 
  organic 
  substances 
  

   progressing 
  in 
  the 
  flask 
  or 
  whether 
  it 
  originates 
  in 
  the 
  living 
  

   protoplasm. 
  I 
  would 
  point 
  out, 
  however, 
  that 
  if 
  it 
  was 
  found 
  

   that 
  the 
  minute 
  organisms 
  of 
  the 
  plankton 
  entangled 
  or 
  

   abstracted 
  radioactive 
  substances 
  from 
  the 
  water, 
  and 
  in 
  this 
  

   way 
  held 
  them 
  in 
  suspension, 
  then 
  a 
  satisfactory 
  explanation 
  

   of 
  the 
  remarkable 
  A^ariations 
  in 
  the 
  radioactivity 
  of 
  different 
  

   parts 
  of 
  the 
  ocean 
  is 
  forthcoming. 
  Whereas 
  chemical 
  con- 
  

   ditions 
  in 
  general 
  are 
  fairly 
  constant 
  over 
  the 
  extent 
  of 
  the 
  

   ocean 
  it 
  is 
  quite 
  otherwise 
  with 
  organic 
  life. 
  It 
  is 
  well- 
  

   known 
  that 
  in 
  bacterial 
  distribution, 
  for 
  instance, 
  the 
  numbers 
  

   are 
  very 
  much 
  greater 
  near 
  shore 
  and 
  are 
  extremely 
  variable 
  

   over 
  the 
  surface 
  of 
  the 
  sea. 
  But, 
  of 
  course, 
  the 
  present 
  

   experiments 
  are 
  too 
  few 
  in 
  number 
  to 
  justify 
  any 
  discussion 
  

   of 
  the 
  question 
  ; 
  further 
  experiments 
  may 
  throw 
  light 
  on 
  the 
  

   matter. 
  I 
  hope 
  shortly 
  to 
  have 
  surface 
  and 
  sub-surface 
  

   waters 
  at 
  my 
  disposal 
  : 
  a 
  comparison 
  of 
  these 
  will 
  be 
  of 
  

   interest. 
  In 
  connexion 
  with 
  this 
  subject 
  I 
  think 
  it 
  is 
  instruc- 
  

   tive 
  to 
  recall 
  an 
  interesting 
  experiment 
  of 
  Eve 
  and 
  Mcintosh 
  * 
  

   (and 
  one 
  which 
  I 
  have 
  contirmed 
  in 
  different 
  forms 
  and 
  

   degrees), 
  as 
  to 
  the 
  concealment 
  of 
  the 
  emanation 
  in 
  solutions 
  

   wherein 
  any 
  trace 
  of 
  precipitate 
  may 
  have 
  developed. 
  

   Eve 
  and 
  Mcintosh 
  found 
  that 
  a 
  little 
  sulphuric 
  acid 
  

   added 
  to 
  a 
  rock 
  solution 
  reduced 
  the 
  evolution 
  of 
  the 
  

   emanation 
  to 
  one-fifth 
  of 
  what 
  it 
  had 
  previously 
  been. 
  The 
  

   * 
  Phil. 
  Mag. 
  Aug. 
  1907. 
  

  

  