Am.  Jour,  riiarm.  1 
June,  1881.  / 
Testing  of  Peru  Balsam. 
301 
is  shaken  with  carbon  bisulphide  the  latter  is  taken  up  by  the  solvent, 
whereby  an  (apparent)  increase  of  the  cinnaraein  will  appear.  If  this 
is  saponified  with  alcoholic  soda^  and  carbonic  acid  gas  then  passed 
through  the  liquid,  in  order  to  remove  the  excess  of  soda  as  carbonate, 
the  filtrate  ^vill  contain,  besides  sodium  cinnamate,  also  the  sodium 
salts  of  the  fatty  acids,  and  these  latter  would  then  be  separated  by 
boiling  water  from  the  acidulated  solution  of  their  salts,  and  from  the 
cinnamic  and  benzoic  acids.  The  adulteration  of  pure  balsam  with 
fatty  oils  may,  therefore,  in  the  further  elucidation  remain  out  of  con- 
sideration. 
For  the  remaining  admixtures  which,  according  to  the  nature  of  the 
case,  may  be  of  service  to  the  adulterator,  the  author  believes  to  have 
found  a  good  means  of  recognition,  which,  with  consideration  of  the 
already  indicated,  somewhat  confined  decomposition  of  the  balsam,  was 
sufficiently  apparent. 
By  boiling  with  milk  of  lime  there  is  extracted  therefrom,  as  the 
above  experiments  show,  for  the  most  part  simply  cinnamic  acid,  and 
upon  the  filter  there  remains  a  soft,  friable  mass.  Slaked  lime  in  a  dry 
condition  exerts  the  same  slight  action.  If  two  parts  of  the  balsam  are 
triturated  with  one  part  of  slaked  lime,  the  properties  of  the  mixture 
are  changed  no  more  than  would  be  expected ;  a  smeary,  or,  at  all 
events,  a  soft,  kneadable  or  somewhat  friable,  readily  divisible  mass  is 
obtained,  which,  even  after  long  exposure  in  the  water -bath,  does  not 
harden.  The  specimens  of  balsam  at  the  author's  disposition  which, 
according  to  their  specific  gravity,  odor  or  behavior  to  Grote's  ammo- 
nia test,  were  recognized  as  adulterated,  furnish,  on  the  contrary,  very 
hard,  no  longer  kneadable  masses,  when  they  are  rubbed  together  with 
half  their  weight  of  slaked  lime.  The  same  behavior  was  shown  by 
specimens  of  balsam  to  which  styrax,  benzoin  (evaporated  alcoholic 
solution),  copaiba  and  colophony  were  added  in  amounts  of  10  per 
cent,  or  more.  In  every  case  the  adulterated  balsam  solidifies  with 
the  lime.  This  lime  test  appears,  therefore,  to  be  of  constant' value, 
and  in  its  simplicity  leaves  nothing  to  be  desired.  If  the  test  is  con- 
firmed, it  may  be  exacted  that  10  di^ops  of  Peru  balsam  shall  fmiiish 
with  'Jf  grams  of  slaked  lime  a  mixture  which  remains  soft;  the  amount 
of  lime  is  here  intentionally  made  somewhat  large,  10  drops  of  balsam 
weighing  scarcely  '6  gram.  Dr.  Grote,  who  has  treated  the  subject  so 
minutely  and  successfully,  writes  that  his  observations  agree  with 
those  of  the  author  in  regard  to  the  action  of  the  slaked  lime.  It 
