﻿ITS 
  PRODUCTS 
  OF 
  DECOMPOSITION. 
  59 
  

  

  Regnault's 
  own 
  results 
  ; 
  the 
  highest 
  amount 
  obtained 
  for 
  the 
  carbon 
  being 
  0-63 
  

   per 
  cent, 
  below 
  the 
  calculation, 
  while 
  the 
  lowest 
  differs 
  by 
  more 
  than 
  one 
  per 
  cent., 
  

   and 
  the 
  mean 
  of 
  the 
  whole 
  four 
  gives 
  0*77 
  too 
  little 
  carbon, 
  involving 
  a 
  loss 
  which 
  

   could 
  not 
  possibly 
  have 
  occurred 
  in 
  carefully 
  made 
  analyses. 
  

  

  Partly 
  on 
  account 
  of 
  this 
  difference, 
  and 
  partly 
  guided 
  by 
  his 
  views 
  regard- 
  

   ing 
  the 
  divisibility 
  of 
  formulae, 
  Gerhardt 
  was 
  induced 
  to 
  doubt 
  the 
  exactitude 
  of 
  

   Regnault's 
  formula, 
  which 
  presents 
  three 
  different 
  deviations 
  from 
  his 
  law 
  ; 
  the 
  

   number 
  of 
  equivalents 
  of 
  carbon 
  and 
  of 
  oxygen 
  being 
  uneven, 
  and 
  the 
  sum 
  of 
  the 
  

   equivalents 
  of 
  hydrogen 
  and 
  nitrogen 
  also 
  indivisible 
  by 
  two. 
  He 
  therefore 
  

   repeated 
  its 
  analysis, 
  using 
  the 
  crystallised 
  codeine, 
  and 
  obtained 
  the 
  results 
  

   contained 
  in 
  the 
  table, 
  and 
  deduced 
  from 
  them 
  the 
  formula 
  C 
  36 
  H 
  21 
  NO 
  G 
  for 
  the 
  

   anhydrous 
  base, 
  which 
  gives 
  the 
  calculated 
  results 
  : 
  

  

  

  Anhydrous. 
  

  

  Crystallised, 
  

  

  Carbon, 
  

  

  72-24 
  

  

  68-13 
  

  

  Hydrogen, 
  

  

  7-02 
  

  

  7-25 
  

  

  Nitrogen, 
  . 
  

  

  4-68 
  

  

  4-41 
  

  

  Oxygen, 
  . 
  

  

  16-06 
  

  

  20-11 
  

  

  100-00 
  100-00 
  

  

  and 
  tallies 
  extremely 
  well 
  with 
  his 
  analysis. 
  This 
  formula 
  has, 
  however, 
  been 
  

   again 
  called 
  in 
  question 
  by 
  Dollfus,* 
  who 
  has 
  endeavoured 
  to 
  determine 
  the 
  

   constitution 
  and 
  atomic 
  weight 
  of 
  the 
  alkaloids 
  by 
  the 
  analysis 
  of 
  their 
  hydro- 
  

   sulphocyanates, 
  and 
  obtained 
  from 
  the 
  codeine 
  salt 
  of 
  that 
  acid 
  ; 
  results 
  agree- 
  

   ing 
  with 
  the 
  formula 
  C 
  34 
  H 
  19 
  N0 
  5 
  . 
  Considering 
  the 
  known 
  accuracy 
  of 
  Regnault, 
  

   and 
  of 
  the 
  chemists 
  by 
  whom 
  his 
  formula 
  has 
  been 
  confirmed, 
  I 
  considered 
  it 
  an 
  

   essential 
  preliminary 
  to 
  my 
  investigation 
  to 
  repeat 
  its 
  analysis 
  with 
  all 
  possible 
  

   care, 
  so 
  as 
  to 
  determine 
  which 
  of 
  the 
  two 
  represents 
  its 
  true 
  constitution. 
  

  

  I. 
  Preparation 
  and 
  Analysis 
  of 
  Codeine. 
  

  

  I 
  have 
  little 
  to 
  add 
  to 
  the 
  information 
  we 
  already 
  possess 
  regarding 
  the 
  pre- 
  

   paration 
  of 
  codeine. 
  I 
  have 
  obtained 
  it, 
  as 
  usual, 
  from 
  the 
  mother 
  liquor 
  from 
  

   which 
  morphia 
  has 
  been 
  precipitated 
  by 
  ammonia. 
  As 
  the 
  codeine 
  forms 
  only 
  

   from 
  a 
  sixteenth 
  to 
  a 
  thirtieth 
  of 
  the 
  morphia, 
  it 
  is, 
  of 
  course, 
  mixed 
  in 
  this 
  fluid 
  

   with 
  a 
  corresponding 
  quantity 
  of 
  muriate 
  of 
  ammonia, 
  which 
  must 
  be 
  decomposed 
  

   by 
  potash, 
  in 
  order 
  to 
  obtain 
  it. 
  Much 
  advantage 
  is 
  gained, 
  however, 
  by 
  first, 
  

   evaporating 
  the 
  fluid 
  to 
  crystallisation, 
  and 
  expressing 
  the 
  crystals 
  deposited, 
  as 
  in 
  

   this 
  way 
  the 
  greater 
  part 
  of 
  the 
  muriate 
  of 
  ammonia, 
  which 
  is 
  the 
  more 
  soluble 
  

   salt 
  of 
  the 
  two, 
  is 
  left 
  in 
  solution 
  ; 
  and 
  by 
  repeating 
  the 
  crystallisation 
  many 
  

  

  * 
  Annalen 
  der 
  Chimie 
  und 
  Pharmacie, 
  vol. 
  lxv., 
  p. 
  218. 
  

  

  