﻿46 
  Mr. 
  R. 
  F. 
  D'Arcy 
  on 
  the 
  

  

  The 
  irregularities 
  of 
  August 
  10 
  are 
  to 
  be 
  accounted 
  for 
  by 
  

   the 
  changing 
  weather 
  conditions. 
  The 
  large 
  loss 
  with 
  water 
  

   in 
  exp. 
  vii. 
  was 
  with 
  a 
  wind 
  blowing 
  which 
  did 
  some 
  damage 
  

   in 
  the 
  way 
  of 
  blowing 
  down 
  tents, 
  &c. 
  Observations 
  on 
  days 
  

   such 
  as 
  August 
  13 
  are 
  useful 
  for 
  showing 
  that 
  the 
  effect 
  as 
  

   observed 
  in 
  these 
  experiments 
  is 
  not 
  pronounced 
  except 
  in 
  

   bright 
  sunshine. 
  

  

  The 
  observations 
  of 
  August 
  19 
  have 
  to 
  be 
  considered. 
  

   The 
  day 
  was 
  a 
  very 
  fine 
  one. 
  The 
  dish 
  on 
  this 
  day 
  was 
  very 
  

   completely 
  sheltered 
  from 
  the 
  light 
  north 
  wind 
  by 
  the 
  house. 
  

   The 
  explanation 
  given 
  by 
  the 
  author 
  is 
  that 
  the 
  liquid 
  being 
  

   kept 
  in 
  an 
  unstirred 
  condition, 
  the 
  decomposing 
  molecules 
  of 
  

   H 
  2 
  2 
  were 
  not 
  brought 
  to 
  the 
  surface 
  in 
  anything 
  like 
  as 
  

   large 
  numbers 
  as 
  on 
  other 
  days 
  when 
  the 
  liquid 
  was 
  kept 
  in 
  

   a 
  state 
  of 
  slight 
  agitation 
  by 
  wind. 
  The 
  surface 
  conditions 
  

   may 
  possibly 
  affect 
  the 
  rate 
  of 
  discharge. 
  Moreover, 
  it 
  must 
  

   be 
  borne 
  in 
  mind 
  that 
  the 
  electric 
  field 
  in 
  these 
  experiments 
  

   was 
  very 
  weak. 
  

  

  The 
  effect 
  observed 
  seemed 
  quite 
  independent 
  of 
  the 
  forma- 
  

   tion 
  of 
  bubbles 
  of 
  oxygen. 
  

  

  In 
  some 
  of 
  these 
  experiments, 
  the 
  partial 
  decomposition 
  of 
  

   a 
  dilute 
  solution 
  of 
  hydrogen 
  peroxide 
  in 
  a 
  flask 
  and 
  exposed 
  

   to 
  sunshine 
  for 
  two 
  and 
  a 
  half 
  hours, 
  was 
  used 
  as 
  a 
  con- 
  

   venient 
  " 
  sunshine 
  recorder 
  " 
  during 
  the 
  electrical 
  experi- 
  

   ments. 
  The 
  relative 
  values 
  of 
  the 
  decomposition 
  on 
  August 
  

   11, 
  13, 
  17, 
  and 
  19 
  being 
  90, 
  65, 
  85, 
  65 
  ; 
  numbers 
  which 
  

   indicate 
  that 
  the 
  days 
  on 
  which 
  the 
  radiation 
  is 
  most 
  effective 
  

   in 
  decomposing 
  H 
  2 
  2 
  are 
  also 
  the 
  days 
  on 
  which 
  the 
  dis- 
  

   charging 
  action 
  is 
  most 
  pronounced. 
  

  

  If 
  the 
  origin 
  of 
  the 
  positive 
  and 
  negative 
  ions 
  in 
  the 
  air 
  is 
  

   due 
  to 
  the 
  decomposition 
  of 
  H 
  2 
  2 
  , 
  — 
  this 
  substance 
  being 
  itself 
  

   formed 
  by 
  the 
  interaction 
  of 
  water 
  and 
  free 
  atmospheric 
  

   oxygen, 
  — 
  it 
  would 
  seem 
  that 
  the 
  phenomena 
  of 
  atmospheric 
  

   electricity 
  may 
  be 
  traced 
  to 
  the 
  action 
  of 
  plants, 
  if 
  the 
  view 
  

   is 
  correct 
  that 
  the 
  free 
  oxygen 
  of 
  the 
  atmosphere 
  is 
  to 
  be 
  

   attributed 
  to 
  the 
  action 
  of 
  plants 
  (Stevenson, 
  Phil. 
  Mag. 
  

   September 
  & 
  October 
  1900). 
  

  

  These 
  experiments 
  possibly 
  raise 
  the 
  question 
  whether 
  some 
  

   of 
  the 
  experiments 
  which 
  have 
  been 
  described 
  on 
  the 
  action 
  

   of 
  light, 
  especially 
  ultra-violet 
  light, 
  in 
  discharging 
  negative 
  

   electrification 
  may 
  not 
  be 
  due 
  to 
  a 
  moisture-film 
  containing 
  

   some 
  H 
  2 
  2 
  being 
  constantly 
  formed 
  and 
  decomposed. 
  Would 
  

   all 
  these 
  experiments 
  give 
  the 
  same 
  results 
  if 
  the 
  surrounding- 
  

   dielectric 
  was 
  dry 
  nitrogen 
  instead 
  of 
  atmospheric 
  air 
  ? 
  

  

  Perhaps 
  the 
  results 
  of 
  some 
  observers 
  on 
  the 
  alleged 
  loss 
  

   of 
  electrification 
  in 
  the 
  evaporation 
  of 
  water 
  (in 
  air) 
  might 
  

   possibly 
  be 
  similarly 
  explained. 
  

  

  