﻿Mixter 
  — 
  Products 
  of 
  the 
  Explosion 
  of 
  Acetylene. 
  7 
  

  

  for 
  perhaps 
  three 
  to 
  five 
  seconds 
  and 
  burned 
  with 
  a 
  luminous 
  

   but 
  smokeless 
  flame. 
  Two 
  estimations 
  of 
  acetylene 
  in 
  the 
  

   residual 
  gas 
  gave 
  respectively 
  5-2 
  and 
  5*4 
  per 
  cent. 
  

  

  Experiments 
  32 
  and 
  33. 
  — 
  These 
  were 
  made 
  as 
  nearly 
  as 
  

   possible 
  under 
  the 
  same 
  conditions 
  as 
  31. 
  The 
  residual 
  gas 
  in 
  

   82 
  yielded 
  6'6 
  and 
  7 
  per 
  cent 
  of 
  acetylene, 
  and 
  that 
  in 
  33 
  4 
  

   per 
  cent 
  of 
  acetylene. 
  

  

  Experiment 
  3J/,. 
  — 
  Gas, 
  98 
  per 
  cent 
  of 
  acetylene 
  ; 
  pressure 
  

   3 
  atmospheres 
  ; 
  hole 
  2*l 
  mm 
  in 
  diameter. 
  The 
  residual 
  gas 
  

   yielded 
  5*7 
  and 
  5 
  - 
  5 
  per 
  cent 
  of 
  acetylene. 
  

  

  Experiment 
  35. 
  — 
  Pressure 
  3 
  atmospheres 
  ; 
  hole 
  4 
  mm 
  in 
  diam- 
  

   eter. 
  Each 
  of 
  two 
  estimations 
  of 
  acetylene 
  in 
  residual 
  gas 
  

   gave 
  4*2 
  per 
  cent. 
  

  

  Berthellot 
  and 
  Yieille* 
  found 
  in 
  their 
  experiments 
  that 
  the 
  

   pressure 
  in 
  an 
  explosion 
  is 
  about 
  eleven 
  times 
  the 
  initial 
  pres- 
  

   sure, 
  corresponding 
  fairly 
  with 
  the 
  pressure 
  of 
  the 
  gas 
  at 
  the 
  

   calculated 
  temperature 
  of 
  2790° 
  C. 
  In 
  the 
  explosion 
  in 
  the 
  

   bomb 
  above 
  described, 
  the 
  temperature 
  was 
  very 
  high, 
  as 
  

   platinum 
  wire 
  was 
  repeatedly 
  melted 
  and 
  made 
  brittle. 
  But 
  

   a 
  wire 
  in 
  contact 
  with 
  the 
  pipe-stem 
  insulator 
  was 
  not 
  melted. 
  

   The 
  shattering 
  of 
  the 
  glass 
  insulators 
  was 
  undoubtedly 
  due 
  to 
  

   the 
  intense 
  heat, 
  for 
  in 
  no 
  instance 
  was 
  a 
  glass 
  eudiometer 
  

   cracked, 
  the 
  quantity 
  of 
  heat 
  not 
  being 
  sufficient 
  to 
  affect 
  the 
  

   glass. 
  Berthellot 
  and 
  Chatalierf 
  found 
  the 
  velocity 
  of 
  explo- 
  

   sion 
  in 
  narrow 
  tubes 
  at 
  pressures 
  from 
  5 
  to 
  30 
  atmospheres 
  to 
  

   be 
  1000 
  to 
  1600 
  meters 
  per 
  second. 
  In 
  my 
  experiments 
  at 
  3 
  

   atmospheres 
  in 
  glass 
  tubes 
  the 
  velocity 
  was 
  low 
  in 
  some 
  cases. 
  

  

  The 
  experiments 
  1 
  to 
  15 
  were 
  made 
  with 
  an 
  equal 
  number 
  of 
  

   molecules 
  in 
  a 
  unit 
  of 
  space. 
  At 
  325° 
  the 
  decomposition 
  did 
  

   not 
  extend 
  throughout 
  the 
  gas, 
  although 
  here 
  the 
  energy 
  of 
  

   the 
  system 
  was 
  greater 
  than 
  that 
  containing 
  twice 
  as 
  many 
  

   molecules 
  at 
  0° 
  in 
  the 
  same 
  space 
  — 
  a 
  condition 
  in 
  which 
  decom- 
  

   position 
  will 
  propagate 
  itself. 
  In 
  the 
  cool 
  and 
  denser 
  gas 
  the 
  

   molecular 
  impacts 
  are 
  more 
  frequent 
  than 
  in 
  the 
  hot 
  gas. 
  At 
  

   temperatures 
  above 
  325° 
  the 
  decomposition 
  was 
  self 
  propagat- 
  

   ing. 
  Here 
  we 
  have 
  impacts 
  of 
  sufficient 
  frequency 
  to 
  cause 
  

   explosion. 
  It 
  is 
  highly 
  probable 
  that 
  acetylene 
  at 
  400° 
  and 
  

   atmospheric 
  pressure 
  •will 
  not 
  explode. 
  The 
  results 
  at 
  high 
  

   temperatures 
  present 
  the 
  striking 
  fact 
  that 
  the 
  amount 
  of 
  

   acetylene 
  decomposed, 
  or 
  rather 
  the 
  hydrogen 
  remaining, 
  is 
  

   fairly 
  constant 
  in 
  a 
  range 
  of 
  100°, 
  that 
  is, 
  from 
  350° 
  to 
  450°. 
  

   The 
  products 
  at 
  high 
  temperatures 
  and 
  in 
  the 
  U-tube 
  tests 
  were 
  

   essentially 
  alike, 
  consisting 
  of 
  carbon 
  and 
  hydrogen, 
  condensation 
  

   products 
  and 
  acetylene. 
  The 
  wave-like 
  character 
  observed 
  in 
  

   27 
  and 
  28, 
  suggests 
  that 
  the 
  marked 
  variation 
  in 
  the 
  results 
  ob- 
  

  

  * 
  Loc. 
  cit. 
  f 
  Loc. 
  cit. 
  

  

  