﻿752 
  Mr. 
  W. 
  T. 
  Kennedy 
  on 
  the 
  Active 
  Deposit 
  

  

  electrode 
  was 
  about 
  2*3 
  times 
  the 
  maximum 
  active 
  depositor! 
  

   the 
  positive 
  terminal. 
  Repeated 
  measurements 
  have 
  not 
  been 
  

   made 
  to 
  confirm 
  these 
  results, 
  but 
  the 
  same 
  precautions 
  were 
  

   taken 
  with 
  hydrogen 
  as 
  with 
  air 
  and 
  carbon 
  dioxide. 
  It 
  will 
  

   be 
  seen 
  from 
  the 
  values 
  given, 
  that 
  the 
  ratio 
  of 
  the 
  maximum 
  

   activities 
  for 
  the 
  two 
  terminals 
  in 
  the 
  case 
  of 
  hydrogen 
  is 
  

   only 
  slightly 
  less 
  than 
  the 
  corresponding 
  ratios 
  for 
  air 
  and 
  

   carbon 
  dioxide. 
  

  

  IX. 
  Comparison 
  of 
  the 
  Active 
  Deposits 
  in 
  Air^ 
  Carbon 
  

   Dioxide^ 
  and 
  Hydrogen. 
  

  

  For 
  purposes 
  of 
  comparison 
  the 
  active 
  deposits 
  obtained 
  

   under 
  the 
  various 
  circumstances 
  are 
  collected 
  in 
  Table 
  VI. 
  

   From 
  this 
  Table 
  it 
  will 
  be 
  seen 
  that 
  the 
  pressures 
  at 
  which 
  

  

  

  Table 
  VI. 
  

  

  

  Gas. 
  

  

  Aetiye 
  Deposit 
  

   on 
  the 
  Cathode. 
  

  

  Pressure. 
  

  

  Active 
  Deposit 
  

   on 
  the 
  Anode. 
  

  

  Air. 
  

  

  '> 
  

  

  CarboD 
  Dioxide. 
  

   >> 
  

  

  Hydrogen. 
  

  

  20-5 
  

  

  92-0 
  (maximum) 
  

  

  750 
  mm. 
  

   80 
  „ 
  

   17 
  „ 
  

   •5„ 
  

  

  750 
  mm. 
  

  

  60 
  „ 
  

  

  14 
  „ 
  

  

  1 
  „ 
  

  

  760 
  mm. 
  

   250 
  „ 
  

   80 
  „ 
  

   6 
  „ 
  

  

  •45 
  

  

  33'0 
  (maximum) 
  

   11-3 
  

  

  •75 
  

  

  11-7 
  

  

  11-7 
  

  

  82-0 
  (maximum) 
  

  

  31*0 
  (maximum) 
  

   14-7 
  

  

  8-3 
  

  

  15-6 
  

  

  78-3 
  

   108-0 
  (maximum) 
  

  

  46 
  (maximum) 
  

   20 
  

  

  21-0 
  

  

  the 
  maximum 
  cathode 
  deposits 
  were 
  obtained 
  for 
  the 
  difEerent 
  

   gases 
  are 
  — 
  carbon 
  dioxide 
  60 
  mm., 
  air 
  80 
  mm., 
  hydrogen 
  

   250 
  mm. 
  These 
  pressures 
  are 
  approximately 
  in 
  the 
  ratio 
  

   1 
  : 
  1*33 
  : 
  4*2. 
  Now, 
  since 
  the 
  coefficient 
  of 
  diffusion 
  of 
  a 
  gas 
  

   is 
  inversely 
  proportional 
  to 
  the 
  molecular 
  weight 
  of 
  a 
  gas 
  into 
  

   which 
  it 
  is 
  diffused; 
  and 
  since, 
  further, 
  the 
  coefficient 
  of 
  

   diffusion 
  is 
  inversely 
  proportional 
  to 
  the 
  total 
  pressure 
  of 
  the 
  

   two 
  diffusing 
  gases, 
  it 
  follows, 
  since 
  in 
  this 
  case 
  the 
  diffusing 
  

   transmutation 
  product 
  must 
  be 
  exceedingly 
  minute, 
  that 
  the 
  

   coefficient 
  of 
  diffusion 
  for 
  the 
  product 
  will 
  be 
  inversely 
  pro- 
  

   portional 
  to 
  the 
  pressure 
  of 
  the 
  gas 
  into 
  which 
  it 
  is 
  passing. 
  

  

  Further, 
  since 
  the 
  maximum 
  activities 
  on 
  the 
  cathode 
  for 
  

   the 
  different 
  gases 
  are 
  approximately 
  the 
  same, 
  i. 
  e. 
  ^2, 
  93, 
  

   and 
  108, 
  we 
  may 
  look 
  upon 
  the 
  results 
  as 
  due 
  to 
  the 
  diffusion 
  

  

  