﻿10 
  

  

  J. 
  Stan 
  afield 
  — 
  Retarded 
  Diffusion 
  and 
  

  

  relative 
  displacement 
  of 
  the 
  bands, 
  which 
  are 
  doubtless 
  due 
  to 
  

   inequalities 
  of 
  diffusion. 
  Both 
  the 
  inner 
  and 
  outer 
  bands 
  are 
  

   more 
  widely 
  spaced 
  toward 
  the 
  outside. 
  

  

  Numbers 
  12 
  to 
  15 
  show 
  similar 
  bands 
  to 
  those 
  in 
  16 
  to 
  20. 
  

   Numbers 
  1 
  to 
  11 
  show 
  three 
  similar 
  areas, 
  but 
  in 
  1 
  to 
  7 
  there 
  

   appears 
  to 
  be 
  a 
  continuous 
  precipitate 
  round 
  the 
  drop. 
  This 
  

  

  K 
  2 
  Cr0 
  4 
  

  

  

  

  3N 
  

  

  N 
  

  

  N/2 
  

  

  N/10 
  

  

  N/20 
  

  

  AgN0 
  3 
  

  

  N/10 
  

  

  1 
  

  

  2 
  

  

  3 
  

  

  

  

  N/20 
  

  

  4 
  

  

  5 
  

  

  6 
  

  

  7 
  

  

  

  N/40 
  

  

  8 
  

  

  9 
  

  

  10 
  

  

  11 
  

  

  

  N/80 
  

  

  12 
  

  

  13 
  

  

  14 
  

  

  15 
  

  

  

  N/100 
  

  

  16 
  

  

  17 
  

  

  18 
  

  

  19 
  

  

  20 
  

  

  N/200 
  

  

  21 
  

  

  22 
  

  

  23 
  

  

  24 
  

  

  25 
  

  

  N/400 
  

  

  26 
  

  

  27 
  

  

  28 
  

  

  29 
  

  

  30 
  

  

  The 
  strength 
  of 
  the 
  potassium 
  chromate 
  in 
  the 
  drop 
  in 
  an} 
  7 
  experiment 
  is 
  

   given 
  by 
  the 
  heading 
  of 
  the 
  column 
  in 
  which 
  the 
  number 
  falls, 
  the 
  strength 
  

   of 
  the 
  silver 
  nitrate 
  in 
  the 
  gelatine 
  being 
  given 
  at 
  the 
  extreme 
  left, 
  thus 
  in 
  

   the 
  case 
  of 
  number 
  13 
  normal 
  potassium 
  chromate 
  diffused 
  into 
  a 
  gelatine 
  

   containing 
  an 
  eightieth, 
  normal 
  solution 
  of 
  silver 
  nitrate. 
  

  

  is 
  seen 
  to 
  have 
  bands 
  on 
  the 
  surface 
  as 
  with 
  the 
  stronger 
  silver 
  

   solutions 
  cited 
  above. 
  

  

  / 
  1ST 
  \ 
  

  

  The 
  experiments 
  with 
  the 
  weakest 
  silver 
  solutions! 
  ) 
  sh 
  

  

  1 
  \100/ 
  

  

  ow 
  

  

  that 
  bands 
  are 
  not 
  produced 
  unless 
  a 
  certain 
  concentration 
  is 
  

   present. 
  From 
  this 
  it 
  may 
  be 
  argued 
  that 
  the 
  areas 
  between 
  

   the 
  two 
  sets 
  of 
  bands, 
  in 
  numbers 
  1 
  to 
  20, 
  had 
  an 
  insufficient 
  

   concentration 
  of 
  silver 
  ions 
  to 
  allow 
  of 
  the 
  formation 
  of 
  bands, 
  

   as 
  a 
  result 
  of 
  the 
  removal 
  of 
  silver 
  ions 
  by 
  precipitation, 
  the 
  pre- 
  

   cipitation 
  being 
  followed 
  by 
  decrease 
  of 
  concentration 
  outside 
  

   the 
  bands 
  as 
  a 
  result 
  of 
  diffusion 
  of 
  silver 
  ions 
  inward 
  to 
  take 
  the 
  

  

  