﻿ITS 
  PRODUCTS 
  OF 
  DECOMPOSITION. 
  81 
  

  

  ing 
  the 
  bases 
  in 
  solution, 
  collects 
  in 
  the 
  receiver. 
  The 
  decomposition 
  at 
  250°, 
  

   however, 
  is 
  excessively 
  slow, 
  and 
  even 
  after 
  many 
  days, 
  bases 
  are 
  evolved 
  appa- 
  

   rently 
  in 
  undiminished 
  quantity, 
  but 
  1 
  retained 
  the 
  mixture 
  steadily 
  at 
  this 
  point, 
  

   in 
  hopes 
  of 
  obtaining 
  the 
  product 
  free 
  from 
  ammonia, 
  which 
  my 
  preliminary 
  trials 
  

   had 
  shewn 
  to 
  be 
  produced 
  at 
  higher 
  temperatures 
  ; 
  but 
  I 
  found 
  that 
  even 
  with 
  this 
  

   low 
  heat 
  it 
  was 
  evolved 
  always 
  in 
  appreciable, 
  and, 
  in 
  some 
  experiments, 
  even 
  

   in 
  considerable 
  quantity. 
  I 
  therefore 
  gradually 
  raised 
  the 
  temperature 
  to 
  about 
  

   350°, 
  when 
  a 
  larger 
  quantity 
  of 
  base 
  was 
  obtained 
  ; 
  and 
  after 
  the 
  heat 
  had 
  been 
  

   sustained 
  for 
  some 
  time, 
  small 
  crystals 
  made 
  their 
  appearance, 
  which 
  deposited 
  

   themselves 
  in 
  a 
  line 
  round 
  the 
  retort, 
  just 
  above 
  the 
  level 
  of 
  the 
  oil 
  in 
  the 
  bath, 
  

   but 
  which 
  soon 
  rose 
  into 
  and 
  collected 
  in 
  the 
  neck 
  of 
  the 
  retort. 
  

  

  These 
  crystals 
  resemble 
  benzoic 
  acid 
  in 
  their 
  external 
  appearance, 
  and 
  are 
  at 
  

   first 
  perfectly 
  colourless, 
  but 
  soon 
  acquire 
  a 
  brownish 
  shade 
  by 
  exposure 
  to 
  light 
  

   and 
  air. 
  They 
  are 
  a 
  base, 
  and 
  rapidly 
  restore 
  the 
  colour 
  of 
  reddened 
  litmus. 
  

   They 
  are 
  sparingly 
  soluble 
  in 
  water, 
  but 
  readily 
  in 
  acids, 
  and 
  give 
  a 
  precipitate 
  

   with 
  bichloride 
  of 
  platinum. 
  The 
  quantity 
  of 
  this 
  substance 
  obtained 
  was 
  exces- 
  

   sively 
  minute 
  ; 
  and 
  though 
  considerable 
  quantities 
  of 
  codeine 
  were 
  operated 
  upon, 
  

   all 
  that 
  was 
  obtained 
  served 
  only 
  to 
  make 
  the 
  few 
  qualitative 
  experiments 
  now 
  

   detailed. 
  

  

  The 
  watery 
  fluid 
  which 
  collected 
  in 
  the 
  receiver 
  possessed 
  a 
  pungent 
  and 
  

   peculiar 
  smell 
  ; 
  it 
  restored 
  the 
  colour 
  of 
  reddened 
  litmus 
  with 
  great 
  rapidity, 
  and 
  

   gave 
  abundant 
  fumes 
  with 
  hydrochloric 
  acid. 
  On 
  the 
  addition 
  of 
  solid 
  potash, 
  a 
  

   highly 
  volatile 
  and 
  pungent 
  oily 
  base 
  collected 
  as 
  a 
  layer 
  on 
  the 
  surface 
  of 
  the 
  

   fluid, 
  and 
  at 
  the 
  same 
  time 
  a 
  gaseous 
  base 
  escaped 
  along 
  with 
  ammonia. 
  From 
  

   the 
  small 
  quantity 
  of 
  these 
  substances 
  which 
  I 
  was 
  able 
  to 
  obtain, 
  I 
  could 
  not 
  

   attempt 
  to 
  prepare 
  either 
  of 
  them 
  in 
  a 
  pure 
  state. 
  I 
  was 
  therefore 
  under 
  the 
  

   necessity 
  of 
  determining 
  their 
  constitution 
  by 
  the 
  analysis 
  of 
  their 
  platinum 
  salts, 
  

   which 
  can 
  be 
  separated 
  from 
  one 
  another, 
  though 
  not 
  without 
  difficulty. 
  In 
  

   order 
  to 
  prepare 
  these 
  salts, 
  the 
  basic 
  fluid 
  was 
  saturated 
  with 
  hydrochloric 
  acid, 
  

   and 
  evaporated 
  to 
  dryness 
  in 
  the 
  water-bath, 
  when 
  it 
  left 
  behind 
  a 
  beautifully 
  

   crystalline 
  mass, 
  highly 
  soluble 
  in 
  water, 
  and 
  deliquescent 
  in 
  moist 
  air. 
  This 
  

   was 
  dissolved 
  in 
  absolute 
  alcohol, 
  to 
  separate 
  ammonia, 
  and 
  the 
  filtered 
  solution 
  

   mixed 
  with 
  an 
  alcoholic 
  solution 
  of 
  bichloride 
  of 
  platinum, 
  when 
  the 
  platinum 
  

   salts 
  were 
  immediately 
  thrown 
  down 
  as 
  a 
  pale-yellow 
  powder, 
  very 
  sparingly 
  

   soluble 
  in 
  absolute 
  alcohol, 
  but 
  readily 
  dissolved 
  on 
  the 
  addition 
  of 
  water. 
  The 
  

   separation 
  of 
  the 
  two 
  bases 
  is 
  best 
  effected 
  by 
  heating 
  the 
  washed 
  precipitate 
  with 
  

   boiling 
  absolute 
  alcohol, 
  and 
  adding 
  water 
  in 
  small 
  quantities 
  until 
  the 
  whole 
  is 
  

   dissolved. 
  The 
  crystals 
  which 
  deposit 
  on 
  cooling 
  are 
  one 
  of 
  the 
  salts 
  in 
  a 
  state 
  

   of 
  purity, 
  if 
  the 
  process 
  have 
  been 
  properly 
  managed, 
  or, 
  at 
  all 
  events, 
  only 
  

   require 
  a 
  repetition 
  of 
  the 
  process 
  to 
  make 
  them 
  absolutely 
  pure. 
  The 
  salt 
  

   thus 
  obtained 
  is 
  scarcely 
  soluble 
  in 
  absolute 
  alcohol 
  or 
  ether, 
  but 
  is 
  readily 
  

  

  VOL. 
  XX. 
  PART 
  I. 
  Y 
  

  

  