■^'"DecTi882''™'}        Examination  of  Balsam  of  Peru.  609 
One  part  of  In  two  parts  of  Carbon  Bisulphide. 
Peru  balsam,  .    At  most  16  per  cent,  of  resinous  residue. 
The  genuine  samples  varied  from  11  to  16  per  cent. 
Purified  storax,  .    Dissolved  completely  ;  clear  solution. 
Colophony  solution,      Entirely  soluble  ;  perfectly  clear. 
Copaiba  balsam,  .  Dissolved  completely;  quite  clear. 
Castor  oil,            .         Dissolved  completely;  quite  clear. 
Benzoin  solution,  .    60  per  cent,  of  resinous  residue. 
Consequently  if  a  sample  of  Peru  balsam,  when  shaken  with  double 
its  weight  of  carbon  bisulphide,  yields  more  tlian  16  per  cent,  of 
undissolved  resinons  residue,  an  admixture  of  solution  of  benzoin  is 
probable. 
(3j.  Petroleum  spirit  takes  up  from  Peru  balsam  a  light  yellowish 
balsam,  probably  consisting  principally  of  cinnamein  (benzyl  cinna- 
mate).  Upon  saponifying  tbis  with  alcoholic  solution  of  caustic  soda, 
besides  sodium  cinnamate,  benzyl  alcohol  is  obtained,  easily  recognized 
by  its  intense  hyacinth  odor.  By  repeatedly  shaking  Peru  balsam 
with  three  or  four  times  its  quantity  of  petroleum  spirit  half  of  it  is 
dissolved  and  half  remains  undissolved.  The  following  shows  the 
relative  behavior  of  the  other  subtances : 
Shaken  with  Petroleum  Spirit. 
Peru  balsam,     .  .    Half  dissolved. 
Purified  storax,        .         About  one-third  dissolved. 
Benzoin  solution,  .    Only  12  per  cent,  dissolved. 
Colophony  solution,  .  More  than  half  dissolved  (40  joer  cent  of  resin). 
Copaiba  balsam,  .    All  dissolved. 
Castor  oil,    .  .         All  dissolved. 
Consequently  if  a  sample  of  balsam  gives  up  more  than  50  per  cent, 
to  petroleum  spirit  an  admixture  of  copaiba  balsam  or  castor  oil  is 
indicated. 
B.  Behavior  of  Peru  Balsam  toioards  Caustic  Lime. — When  Peru 
balsam  is  mixed  with  dried  calcic  hydrate  no  saponification  or  decom- 
position of  the  cinnamein  contained  in  it  results ;  neither  does  it  take 
place  if  water  or  alcohol  be  added.  The  cinnamein  can  be  extracted 
from  the  mixture  by  means  of  petroleum  spirit,  and  in  a  large  number 
of  experiments  with  Peru  balsam  the  proportion  was  found  to  remain 
constant  at  41  per  cent,  of  the  balsam  used.  From  the  residue  undis- 
solved by  petroleum  spirit  ether  dissolves  out  about  14  per  cent,  of 
styracin,  which  differs  fi'om  cinnamein  in  being  difficultly  soluble  in 
cold  alcohol,  and  in  yielding  ui)on  saponification  with  alcoholic  soda 
solution  not  benzyl  alcohol,  but  cinnamyl  alcohol,  together  Avitli  sodium 
cinnamate. 
39 
