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  Scientific 
  Intelligence. 
  

  

  tively 
  determined 
  from 
  the 
  atomic 
  total 
  absorption 
  coefficients 
  of 
  

   its 
  constituent 
  atoms." 
  The 
  excellent 
  agreement 
  obtained 
  indi- 
  

   cates 
  that 
  this 
  additive 
  property 
  must 
  be 
  quite 
  exact 
  for 
  elements 
  

   from 
  hydrogen 
  to 
  bromine. 
  — 
  Proc. 
  Roy. 
  Soc, 
  94 
  A, 
  510, 
  1918. 
  

  

  h. 
  s. 
  u. 
  

  

  8. 
  The 
  Nature 
  of 
  Sun-Spots. 
  — 
  A 
  recent 
  paper 
  (in 
  abstract 
  

   form) 
  by 
  G. 
  E. 
  Hale 
  contains 
  an 
  interesting 
  summary 
  of 
  the 
  

   most 
  important 
  results 
  obtained 
  from 
  three 
  lines 
  of 
  experimental 
  

   attack 
  which 
  were 
  begun 
  at 
  the 
  Kenwood 
  Observatory 
  in 
  1891 
  

   and 
  which 
  have 
  been 
  continued 
  at 
  the 
  Yerkes 
  and 
  Mount 
  Wilson 
  

   Observatories. 
  

  

  It 
  has 
  been 
  found 
  that 
  the 
  spectral 
  lines 
  in 
  sun-spots 
  are 
  split 
  

   into 
  components 
  and 
  polarized 
  in 
  precisely 
  the 
  same 
  manner 
  as 
  

   in 
  laboratory 
  experiments 
  on 
  the 
  Zeeman 
  effect. 
  Accordingly, 
  

   the 
  evidence 
  that 
  sun-spots 
  are 
  electric 
  vortices 
  is 
  very 
  strong. 
  

   ' 
  ' 
  The 
  magnetic 
  polarities 
  and 
  field-strengths 
  of 
  all 
  sun-spots 
  are 
  

   now 
  recorded 
  daily 
  at 
  Mount 
  Wilson 
  with 
  a 
  150-foot 
  tower 
  tele- 
  

   scope, 
  affording 
  data 
  for 
  the 
  determination 
  of 
  the 
  law 
  of 
  solar 
  

   storms. 
  ' 
  ' 
  A 
  large 
  proportion 
  of 
  all 
  sun-spots 
  are 
  double, 
  the 
  two 
  

   members 
  exhibiting 
  opposite 
  magnetic 
  polarity. 
  The 
  preceding 
  

   members 
  of 
  such 
  pairs 
  in 
  the 
  northern 
  and 
  southern 
  solar 
  hemis- 
  

   pheres 
  are 
  of 
  opposite 
  polarity, 
  indicating 
  opposite 
  directions 
  

   of 
  whirls, 
  as 
  in 
  terrestrial 
  cyclones. 
  A 
  comparison 
  of 
  the 
  polari- 
  

   ties 
  of 
  spots 
  preceding 
  the 
  sun-spot 
  minimum, 
  which 
  occurred 
  

   in 
  1912, 
  with 
  those 
  of 
  spots 
  studied 
  after 
  this 
  mimimum, 
  shows 
  

   that 
  the 
  polarity 
  of 
  homologous 
  spots 
  of 
  groups 
  in 
  the 
  same 
  

   hemisphere 
  has 
  been 
  reversed. 
  "Thus 
  the 
  polarities 
  seem 
  to 
  be 
  

   intimately 
  connected 
  with 
  the 
  cause 
  of 
  the 
  sun-spot 
  cycle." 
  

   Investigations 
  of 
  the 
  Zeeman 
  effect 
  in 
  sun-spots 
  give 
  the 
  direc- 
  

   tion 
  of 
  the 
  lines 
  of 
  force 
  of 
  the 
  magnetic 
  field, 
  and 
  hence 
  also 
  of 
  

   that 
  of 
  the 
  axis 
  of 
  the 
  electric 
  vortex. 
  This 
  axis 
  is 
  found 
  to 
  be 
  

   approximately 
  normal 
  to 
  the 
  sun's 
  surface. 
  A 
  fruitful 
  guide 
  

   in 
  the 
  study 
  of 
  sun-spots 
  has 
  been 
  the 
  working 
  hypothesis 
  that 
  

   the 
  oppositely 
  polarized 
  doublets 
  represent 
  the 
  extremities 
  of 
  

   semi-circular 
  vortex 
  rings, 
  extending 
  beneath 
  the 
  photosphere 
  

   and 
  lying 
  in 
  planes 
  normal 
  to 
  the 
  general 
  solar 
  surface. 
  "A 
  

   search 
  for 
  direct 
  evidence 
  of 
  the 
  existence 
  of 
  electric 
  fields 
  in 
  the 
  

   sun 
  has 
  hitherto 
  yielded 
  negative 
  results." 
  — 
  Proc. 
  Boy. 
  Soc, 
  95 
  

   A, 
  234, 
  1919. 
  h. 
  s. 
  u. 
  

  

  9. 
  Surface 
  Tension 
  and 
  Surface 
  Energy 
  and 
  Their 
  Influence 
  

   on 
  Chemical 
  Phenomena, 
  Second 
  Edition; 
  by 
  R. 
  S. 
  Willows 
  and 
  

   E. 
  Hatschek. 
  Pp. 
  viii, 
  115. 
  Philadelphia, 
  1919 
  (P. 
  Blakis- 
  

   ton's 
  Son 
  & 
  Co.). 
  — 
  "The 
  object 
  of 
  the 
  work 
  is 
  to 
  give 
  the 
  stu- 
  

   dent 
  of 
  chemistry 
  an 
  adequate 
  idea 
  of 
  the 
  fundamental 
  laws 
  of 
  

   surface 
  tension 
  and 
  surface 
  energy 
  . 
  . 
  . 
  and 
  then 
  to 
  deal 
  at 
  

   some 
  length 
  with 
  the 
  relations 
  between 
  surface 
  energy 
  and 
  such 
  

   constants 
  and 
  phenomena 
  as 
  are 
  likely 
  to 
  be 
  of 
  interest 
  to 
  the 
  

   chemist 
  and 
  biologist." 
  The 
  second 
  edition 
  has 
  been 
  very 
  appre- 
  

  

  