﻿Chemistry 
  and 
  Physics. 
  417 
  

  

  the 
  two 
  portions 
  of 
  water, 
  even 
  after 
  fourteen 
  days. 
  If 
  how- 
  

   ever 
  the 
  shade 
  was 
  removed 
  the 
  litmus 
  responded 
  in 
  a 
  day 
  or 
  two. 
  

   Nor 
  did 
  the 
  action 
  of 
  sodium 
  peroxide, 
  either 
  with 
  or 
  without 
  

   acid, 
  effect 
  the 
  oxidation 
  of 
  dissolved 
  nitrogen. 
  His 
  later 
  experi- 
  

   ments 
  were 
  directed 
  to 
  test 
  the 
  effect 
  of 
  pressure 
  in 
  the 
  oxidation 
  

   of 
  nitrogen 
  by 
  oxygen 
  gas 
  under 
  the 
  action 
  of 
  the 
  electric 
  dis- 
  

   charge. 
  A 
  suitable 
  mixture 
  of 
  nitrogen 
  and 
  oxygen, 
  standing 
  in 
  

   an 
  inverted 
  test 
  tube 
  over 
  alkali, 
  was 
  sparked 
  from 
  a 
  Ruhmkorff 
  

   coil 
  driven 
  by 
  five 
  Grove 
  cells 
  ; 
  and 
  it 
  was 
  found 
  that 
  under 
  a 
  

   total 
  pressure 
  of 
  three 
  atmospheres 
  the 
  mass 
  absorbed 
  was 
  about 
  

   three 
  times 
  that 
  absorbed 
  in 
  the 
  same 
  time 
  under 
  the 
  ordinary 
  

   pressure. 
  He 
  therefore 
  proceeded 
  to 
  repeat 
  the 
  operation 
  on 
  a 
  

   larger 
  scale, 
  using 
  a 
  vessel 
  of 
  250 
  cc 
  and 
  the 
  alternate 
  current 
  dis- 
  

   charge. 
  To 
  protect 
  the 
  glass, 
  the 
  top 
  of 
  which 
  came 
  nearly 
  in 
  

   contact 
  with 
  the 
  electric 
  flame, 
  as 
  well 
  as 
  to 
  facilitate 
  the 
  absorp- 
  

   tion, 
  the 
  alkali 
  was 
  thrown 
  on 
  to 
  the 
  glass 
  immediately 
  above 
  the 
  

   flame 
  in 
  the 
  form 
  of 
  a 
  fountain, 
  thus 
  washing 
  the 
  entire 
  internal 
  

   surface. 
  At 
  atmospheric 
  pressure, 
  however, 
  the 
  absorption 
  was 
  

   but 
  1600 
  cc 
  per 
  hour; 
  only 
  one-half 
  the 
  rate 
  already 
  obtained. 
  

   On 
  increasing 
  the 
  capacity 
  of 
  the 
  working 
  vessel, 
  the 
  efficiency 
  

   improved. 
  With 
  a 
  bottle 
  of 
  37() 
  cc 
  capacity, 
  a 
  rate 
  of 
  2000 
  cc 
  pe"r 
  

   hour 
  was 
  attained. 
  With 
  a 
  larger 
  flask, 
  one 
  of 
  3300 
  cc 
  ; 
  while 
  a 
  

   globe 
  of 
  4 
  J 
  liters 
  gave 
  a 
  rate 
  of 
  6800 
  cc 
  per 
  hour. 
  In 
  this 
  latter 
  case, 
  

   ten 
  amperes 
  passed 
  through 
  the 
  primary 
  and 
  there 
  was 
  a 
  poten- 
  

   tial 
  difference 
  of 
  41 
  volts 
  at 
  its 
  terminals. 
  To 
  test 
  the 
  question 
  

   of 
  pressure, 
  a 
  glass 
  globe 
  having 
  a 
  capacity 
  of 
  about 
  7 
  liters 
  was 
  

   used, 
  under 
  a 
  pressure 
  of 
  nearly 
  an 
  additional 
  atmosphere, 
  this 
  

   pressure 
  being 
  obtained 
  by 
  gravity, 
  the 
  feed 
  and 
  return 
  pipes 
  for 
  

   the 
  alkaline 
  fountain 
  as 
  well 
  as 
  the 
  pipe 
  for 
  the 
  supply 
  of 
  water 
  

   to 
  the 
  gas-holder 
  being 
  carried 
  to 
  a 
  higher 
  level 
  than 
  that 
  at 
  

   which 
  the 
  rest 
  of 
  the 
  apparatus 
  stood. 
  The 
  rate 
  of 
  absorption 
  

   (reduced 
  to 
  atmospheric 
  pressure) 
  was 
  6880 
  cc 
  per 
  hour, 
  that 
  con- 
  

   ducted 
  at 
  the 
  ordinary 
  pressure 
  being 
  6600 
  cc 
  . 
  Under 
  half 
  an 
  

   atmosphere 
  the 
  absorption 
  was 
  5600 
  and 
  5700 
  cc 
  per 
  hour. 
  Hence 
  

   it 
  would 
  appear 
  that 
  pressure 
  is 
  of 
  advantage 
  only 
  where 
  the 
  

   space 
  is 
  too 
  confined 
  to 
  admit 
  of 
  the 
  best 
  efficiency 
  at 
  a 
  given 
  

   pressure 
  being 
  reached. 
  The 
  author 
  next 
  sought 
  to 
  obtain 
  a 
  high 
  

   rate 
  of 
  absorption 
  by 
  employing 
  a 
  powerful 
  electric 
  flame 
  con- 
  

   tained 
  in 
  a 
  large 
  vessel 
  whose 
  walls 
  were 
  washed 
  internally 
  by 
  an 
  

   alkaline 
  fountain. 
  The 
  flame 
  was 
  obtained 
  by 
  means 
  of 
  a 
  Swin- 
  

   burne 
  transformer 
  insulated 
  with 
  oil, 
  which 
  gave 
  on 
  open 
  sec- 
  

   ondary 
  nearly 
  8000 
  volts; 
  but 
  which 
  when 
  the 
  discharge 
  was 
  

   passing 
  fell 
  to 
  2000. 
  In 
  its 
  primary 
  circuit 
  a 
  self-induction 
  coil 
  

   was 
  placed 
  provided 
  with 
  an 
  adjustable 
  core 
  of 
  iron 
  wires. 
  When 
  

   in 
  operation 
  the 
  potential 
  difference 
  at 
  the 
  primary 
  terminals 
  was 
  

   only 
  30 
  volts, 
  the 
  current 
  passing 
  being 
  40 
  amperes. 
  But 
  since 
  

   the 
  reduction-factor 
  — 
  the 
  cosine 
  of 
  the 
  angle 
  of 
  lag 
  — 
  is 
  about 
  two- 
  

   thirds, 
  the 
  watts 
  expended 
  are 
  only 
  about 
  800 
  in 
  place 
  of 
  1200, 
  

   the 
  product 
  of 
  30 
  by 
  40; 
  so 
  that 
  the 
  rate 
  of 
  energy 
  consumption 
  

   was 
  a 
  little 
  more 
  than 
  a 
  horse-power. 
  The 
  working 
  vessel 
  was 
  

  

  