﻿302 
  Mr. 
  McClung 
  on 
  the 
  Rate 
  of 
  Recombination 
  of 
  

  

  was 
  removed 
  and 
  the 
  air 
  condenser, 
  to 
  be 
  determined, 
  in- 
  

   troduced, 
  and 
  the 
  rate 
  of 
  leak 
  taken 
  again. 
  A 
  third 
  obser- 
  

   vation 
  was 
  then 
  taken 
  without 
  any 
  condenser 
  in 
  the 
  circuit 
  

   at 
  all. 
  

  

  Now 
  by 
  comparing 
  the 
  last 
  observation 
  with 
  that 
  obtained 
  

   when 
  the 
  condenser 
  of 
  known 
  capacity 
  was 
  in 
  circuit, 
  the 
  

   capacity 
  o£ 
  the 
  electrometer, 
  connexions, 
  and 
  plate-electrodes 
  

   was 
  determined. 
  Then, 
  having 
  obtained 
  this 
  capacity, 
  

   that 
  of 
  the 
  air 
  condenser 
  was 
  determined 
  by 
  a 
  compa- 
  

   rison 
  of 
  the 
  deflexions 
  obtained 
  in 
  the 
  second 
  and 
  third 
  

   observations. 
  

  

  This 
  method 
  of 
  determining 
  capacities 
  was 
  found 
  to 
  be 
  

   much 
  more 
  satisfactory 
  than 
  the 
  method 
  of 
  mixtures. 
  The 
  

   capacity 
  of 
  the 
  electrometer, 
  connexions, 
  &c, 
  was 
  found 
  to 
  be 
  

   •00016 
  of 
  a 
  microfarad, 
  while 
  that 
  of 
  the 
  air 
  condenser 
  was 
  

   *00364 
  of 
  a 
  microfarad. 
  

  

  Consideration 
  of 
  other 
  Gases. 
  

  

  This 
  question 
  of 
  recombination 
  of 
  ions 
  was 
  investigated 
  

   also 
  in 
  the 
  case 
  of 
  carbonic 
  acid 
  gas 
  and 
  hydrogen 
  gas. 
  The 
  

   same 
  method 
  was 
  employed 
  as 
  for 
  air. 
  The 
  recombination 
  

   of 
  the 
  ions 
  in 
  these 
  gases 
  under 
  different 
  pressures 
  could 
  not, 
  

   however, 
  be 
  satisfactorily 
  investigated, 
  as 
  the 
  supply 
  of 
  gas 
  

   was 
  limited 
  in 
  each 
  case 
  and 
  no 
  means 
  of 
  filling 
  the 
  cylinder 
  

   with 
  these 
  gases, 
  under 
  increased 
  pressure, 
  was 
  at 
  our 
  disposal. 
  

   The 
  results 
  given 
  here, 
  therefore, 
  for 
  carbon 
  dioxide 
  and 
  

   hydrogen 
  are 
  for 
  these 
  gases 
  under 
  a 
  pressure 
  just 
  slightly 
  

   above 
  atmospheric 
  pressure. 
  The 
  pressure 
  was 
  a 
  few 
  millimetres 
  

   above 
  that 
  of 
  the 
  atmosphere, 
  in 
  consequence 
  of 
  the 
  pressure 
  

   of 
  a 
  short 
  column 
  of 
  the 
  acid, 
  from 
  which 
  the 
  gas 
  was 
  gene- 
  

   rated 
  in 
  each 
  case, 
  in 
  the 
  generating 
  apparatus. 
  In 
  the 
  case 
  

   of 
  both 
  hydrogen 
  and 
  carbon 
  dioxide, 
  it 
  was 
  tested 
  whether 
  

   the 
  ions 
  in 
  these 
  gases 
  followed 
  the 
  same 
  law 
  of 
  recombination 
  

   as 
  was 
  found 
  to 
  hold 
  in 
  the 
  case 
  of 
  air. 
  The 
  law 
  was 
  found 
  

   to 
  be 
  the 
  same 
  in 
  these 
  gases 
  as 
  in 
  air. 
  A 
  comparison 
  of 
  the 
  

   experimental 
  and 
  theoretical 
  curves 
  is 
  shown 
  for 
  carbon 
  

   dioxide 
  and 
  hydrogen 
  in 
  fig. 
  8. 
  

  

  The 
  agreement 
  between 
  theory 
  and 
  experiment 
  in 
  these 
  

   two 
  gases 
  is 
  therefore 
  seen 
  to 
  be 
  as 
  close 
  as 
  is 
  the 
  case 
  w 
  r 
  ith 
  

   xiir. 
  The 
  indications 
  are 
  then 
  that 
  this 
  law 
  of 
  recombination 
  

   of 
  the 
  ions 
  is 
  an 
  invariable 
  one. 
  It 
  has 
  been 
  shown 
  con- 
  

   clusively 
  by 
  this 
  research, 
  that 
  the 
  rate 
  at 
  which 
  ions 
  

   recombine 
  is 
  governed 
  by 
  this 
  law 
  in 
  the 
  cases 
  of 
  air, 
  carbon 
  

   dioxide, 
  and 
  hydrogen. 
  

  

  