﻿Chi 
  Phosphorus 
  Emanation 
  in 
  Spherical 
  Condensers. 
  81 
  

  

  relation 
  of 
  potential 
  and 
  time, 
  at 
  least 
  within 
  the 
  first 
  7 
  

   minutes 
  of 
  discharge. 
  This 
  constant 
  current 
  was 
  not 
  appre- 
  

   ciably 
  modified 
  by 
  stopping 
  the 
  lower 
  tubulure 
  of 
  the 
  reso- 
  

   nator 
  with 
  cotton, 
  nor 
  after 
  vigorously 
  airing 
  it 
  out 
  ; 
  neither 
  

   was 
  there 
  any 
  marked 
  change 
  of 
  current 
  even 
  after 
  30 
  

   minutes. 
  

  

  This 
  interesting 
  result 
  was 
  not, 
  however, 
  borne 
  out 
  by 
  

   longer 
  single 
  periods 
  of 
  observation 
  (20 
  minutes). 
  Marked 
  

   curvature 
  was 
  eventually 
  in 
  evidence, 
  which 
  did 
  not 
  seem* 
  

   referable 
  to 
  leakage 
  errors. 
  Moreover, 
  the 
  conduction 
  de- 
  

   creased 
  in 
  succeeding 
  curves, 
  apparently 
  indicating 
  a 
  dimi- 
  

   nution 
  of 
  the 
  ionization 
  due 
  to 
  the 
  phosphorus. 
  Possibly 
  the 
  

   activity 
  of 
  phosphorus 
  may 
  be 
  quenched 
  by 
  its 
  own 
  emana- 
  

   tion 
  iii 
  the 
  lapse 
  of 
  time, 
  but 
  the 
  discrepancy 
  is 
  liable 
  to 
  be 
  

   hygrometric. 
  

  

  4. 
  A 
  systematic 
  series 
  of 
  experiments 
  was 
  now 
  carried 
  

   through 
  with 
  receivers 
  ranging 
  in 
  diameter 
  from 
  2R=:3 
  to 
  

   2R 
  = 
  23 
  centims. 
  The 
  results 
  were 
  surprisingly 
  irregular 
  

   seeing 
  that 
  some 
  pains 
  was 
  taken 
  with 
  the 
  work, 
  but 
  they 
  

   mapped 
  out 
  a 
  graph 
  of 
  an 
  exponential 
  character 
  to 
  which 
  

   different 
  interpretations 
  may 
  be 
  given. 
  To 
  repeat 
  them 
  here 
  

   would 
  carry 
  me 
  too 
  far. 
  

  

  5. 
  Before 
  continuing 
  the 
  work 
  it 
  seemed 
  advisable 
  to 
  make 
  

   trials 
  to 
  secure 
  more 
  perfect 
  insulation. 
  No 
  means 
  were 
  

   found 
  for 
  removing 
  leakage 
  in 
  the 
  apparatus 
  perfectly 
  

   (paraffin, 
  rubber, 
  &c. 
  were 
  tried 
  in 
  succession 
  with 
  no 
  ad- 
  

   vantage); 
  and 
  a 
  dry 
  clean 
  glass 
  stem, 
  C, 
  fig. 
  1, 
  held 
  in 
  place 
  

   by 
  a 
  wide 
  hard-rubber 
  sheath 
  F, 
  seemed 
  the 
  best 
  remedy. 
  

  

  Experiments 
  were 
  then 
  tried 
  to 
  ascertain 
  the 
  difference 
  

   between 
  a 
  condenser 
  closed 
  as 
  above 
  and 
  one 
  left 
  open 
  for 
  

   the 
  stem 
  to 
  pass 
  through, 
  as 
  shown 
  in 
  fig. 
  2. 
  Here 
  the 
  wire 
  

   and 
  plug 
  attachment 
  puts 
  the 
  outer 
  surface 
  to 
  earth 
  at 
  E. 
  

   The 
  closed 
  condenser 
  always 
  introduced 
  the 
  larger 
  leakage. 
  

   Care 
  must 
  be 
  taken 
  to 
  avoid 
  friction 
  in 
  manipulating 
  the 
  

   stem. 
  

  

  6. 
  Conformably 
  with 
  the 
  experience 
  gained, 
  the 
  condenser 
  

   in 
  the 
  following 
  experiments 
  is 
  left 
  open 
  above, 
  as 
  seen 
  in 
  

   fig. 
  2, 
  and 
  is 
  put 
  to 
  earth 
  at 
  E 
  by 
  a 
  brass 
  plug 
  wedged 
  into 
  

   the 
  neck. 
  The 
  glass 
  tube, 
  C, 
  terminating 
  in 
  the 
  ball 
  of 
  

   phosphorus 
  P, 
  is 
  kept 
  clean 
  and 
  dry, 
  and 
  extends 
  to 
  30 
  centims. 
  

   above 
  the 
  condenser. 
  Unfortunately 
  there 
  is 
  some 
  escape 
  of 
  

   ions 
  around 
  the 
  neck 
  and 
  the 
  access 
  of 
  air 
  here 
  is 
  a 
  menace, 
  

   but 
  there 
  seems 
  to 
  be 
  no 
  way 
  out 
  of 
  the 
  dilemma. 
  

  

  To 
  estimate 
  the 
  loss 
  of 
  ionizing 
  activity 
  of 
  the 
  phosphorus 
  

   pellicle 
  one 
  of 
  the 
  condensers 
  (K. 
  6 
  and 
  K4 
  respectively) 
  was 
  

   treated 
  as 
  a 
  standard, 
  and 
  observations 
  were 
  made 
  upon 
  this 
  

  

  Phil. 
  Mag. 
  S. 
  6\ 
  Vol. 
  3. 
  No. 
  13. 
  Jan. 
  1902. 
  G 
  

  

  