Am.        Pharm. }        Determination  of  Morphine.  705 
solution,  its  strength  being  determined  by  means  of  iodine  without 
any  previous  evaporation. 
Volume  of  Na2S203  solu- 
tion used  in  titration. 
Blank  experiment    4.50  Cc. 
Determination  A  (after  HQ)    4.45  Cc. 
Determination  B  (after  CH3COOH)    4.15  Cc. 
The  acetic  acid  itself  had  no  influence  on  the  iodine.  When  25  Cc. 
of  the  standard  iodine  solution  was  allowed  to  stand  for  2^  hours 
with  10  Cc.  of  the  same  glacial  acetic  acid  as  that  used  above,  no 
solid  separated.  The  mixture  was  diluted  and  titrated  with  sodium 
thiosulphate. 
Volume  of  Iodine  solution.  Volume  of  Acetic  Acid.      Volume  of  Na2S203  solution  required. 
25.0  Cc.  10.0  Cc.  25.4  Cc. 
25.0  Cc.  0.0  Cc.  25.4  Cc. 
Experiment  20. — This  was  conducted  on  the  same  lines  as  Ex- 
periment 19,  but  sulphuric  acid  (2  Cc.  concentrated  acid  suitably 
diluted)  was  used  instead  of  hydrochloric.  The  stock  solution  of 
morphine  sulphate  not  being  the  same,  a  separate  "  blank  "  was  nec- 
essary for  comparison  of  strength. 
Solution  Evaporated        "  Blank  " 
with  H2S04  Experiment. 
Sodium  thiosulphate  solution  used  in  titration....    7.7  Co.  7.4  Cc. 
Experiment  21. — This  was  conducted  on  the  same  lines  as  the 
foregoing  experiments,  substituting  a  considerable  excess  (about 
0.5  Gm.)  of  salicylic  acid  for  the  acids  previously  used.  The  stock 
solution  of  morphine  was  not  the  same. 
Solution  Evaporated  with     "  Blank" 
Salicylic'Acid.  Experimert. 
Sodium  thiosulphate  solution  used  in  titration..    17.55  Cc.  17-50  Cc. 
The  Reactions  of  Morphine  Tartrate.  Experiment  22. — A  solu- 
tion was  made  containing  0.3  Gm.  of  morphine  tartrate  (B.  P.)  in 
10  Cc.  of  water.  The  following  tests  were  applied  to  different 
portions. 
A.  With  ammonium  hydroxide,  the  white  crystalline  precipitate, 
characteristic  of  morphine,  was  obtained. 
B.  With  iodine  dissolved  in  potassium  iodide  and  water,  acidified 
with  sulphuric  acid,  a  characteristic  precipitate  formed. 
