794 
Determination  of  Morphine.       f  Am  jour,  ph  arm. 
'  r  1       Nov.,  1918. 
Titration  results: 
Total  acid  used  =  25.00  Cc. 
Acid  equivalent  to  the  alkali  =  15.90  Cc. 
Acid  equivalent  to  the  morphine  =  9.10  Cc. 
Weight  of  morphine  found  by  titration  =  0.2730  Grh. 
Equivalent  to  0.6006  Gm.  in  the  original  solution.  [Amount 
actually  present  0.6000  Gm.] 
The  Action  of  Barium  Hydroxide  on  Constituents  of  Pills  not 
Present  in  Previous  Deter  imitations.  Experiment  28.  Gum  Tra- 
gacanth. — A  strong  solution  of  gum  tragacanth  was  prepared  which 
was,  alone,  quite  unfilterable.  To  it  was  added  its  own  volume  of 
a  cold  saturated  solution  of  barium  hydroxide.  The  gum  was  pre- 
cipitated and  the  liquid  filtered  readily. 
Experiment  29. — Gum  Acacia. — An  aqueous  solution  (10  per 
cent.)  of  this  gum  was  prepared.  Two  portions  of  50  Cc.  each 
were  taken. 
Portion  A  was  diluted  to  100  Cc.  with  water. 
Portion  B  was  diluted  to  100  Cc.  with  a  cold  saturated  solution 
of  barium  hydroxide.  No  precipitate  formed.  The  two  solutions 
were  filtered  side  by  side  under  as  nearly  as  possible  the  same  con- 
ditions. It  was  at  once  evident  that  B  filtered  more  rapidly  than  A. 
When  46  Cc.  of  filtrate  had  been  collected  from  B,  only  26  Cc.  had 
been  collected  from  A. 
A  further  test  was  made  by  dissolving  6  Gm.  of  gum  acacia  in 
water  and  treating  it  entirely  as  though  a  morphine  determination 
were  being  made.  It  was  submitted  to  all  the  treatment  detailed 
under  Experiment  23.  There  was  no  tendency  to  form  an  emulsion 
with  the  chloroform-alcohol  mixture. 
Experiment  30.  Soap. — The  presence  of  soap,  or  some  such 
constituent  of  a  pill  as  would  react  chemically  with  barium  hydroxide, 
calls  for  slightly  modified  treatment.  The  nature  of  the  modifica- 
tions will  generally  be  obvious,  but  the  following  is  a  fair  example : 
About  6  Gm.  of  laundry  soap  was  dissolved  in  25  Cc.  of  water. 
To  this  was  added  25  Cc.  of  cold  saturated  barium  hydroxide  solu- 
tion, followed  by  5  Gm.  of  barium  hydroxide  dissolved  in.  10  Cc. 
of  hot  water.  The  resulting  mixture  was  cooled,  then  diluted  to 
100  Cc.  with  more  cold  saturated  barium  hydroxide  solution.  After 
thorough  mixing  it  was  filtered.  Examination  of  the  filtrate  showed 
that  barium  hydroxide  was  present  in  such  excess  as  to  insure  that 
any  morphine  originally  mixed  with  the  soap  would  be  held  in  solu- 
