THE  AMERICAN 
JOURNAL  OF  PHARMACY. 
MARCH,  1889., 
ON  THE  SOLUBILITY  OF  SULPHATE  OF  MORPHINE. 
By  Prof.  Frederick  B.  Power,  Ph.D. 
Read  at  the  Pharmaceutical  Meeting,  February  21,  1882. 
My  attention  was  recently  directed,  through  the  reports  of  the 
Committee  on  Descriptive  Chemistry  of  the  Pharmacopoeia^  to  the 
subject  of  the  solubility  of  sulphate  of  morphine  in  water.  As  all 
the  chemical  text-books,  and  other  works  which  I  was  able  to  con- 
sult, state  that  sulphate  of  morphine  is  soluble  in  2  parts  of  cold  water 
(Choulant,  in  Gmelin's  Handbook  of  Chemistry/^  vol.  xvi,  p.  430, 
Husemann's  " Pflanzenstoffe,''  p.  121,  Storer's  ^'Dictionary  of  Chem- 
ical Solubilities,^^  p.  616,^  etc.),  I  was  surprised  to  find  it  stated  in  the 
above-mentioned  report  that  the  salt  requires  15  parts  of  water  at 
15 °C.  (59° F.)  for  solution.  Upon  inquiry  of  my  friend,  Dr.  Charles 
Rice,  I  was  kindly  informed  that  the  commonly  accepted  factor  of 
solubility  is  incorrect,  and  that  from  recent  experiments  15  parts  of 
water  are  indeed  required.  That  the  true  degree  of  solubility  of  a 
salt  so  important,  and  so  frequently  employed,  should  be  correctly 
established  would  seem  very  desirable,  particularly  in  view  of  so  con- 
siderable a  discrepancy. 
In  Storer's  Dictionary,  loc.  cit.,  it  is  stated  on  the  authority  of 
Mohr,  Redwood  and  Procter,  in  connection  with  the  solubility  of  the 
salt,  that  the  cold  solution  contains  33'33  per  cent,  of  it,  which  would 
thus  further  indicate  that  in  dissolving  one  part  of  the  salt  in  2  parts 
of  water,  3  parts  of  solution  are  obtained,  or  an  increase  of  50  per 
cent.,  presumably  by  volume. 
I  have  made  a  few  experiments  on  the  subject,  which  may  be  of 
sufficient  interest  to  receive  a  brief  notice. 
The  sulphate  of  morphine  employed  for  the  determinations  was  that 
^  Al^)stracted  from  Mohr,  Eedwood  and  Procter's  Practical  Pharmacy," 
and  "Ocst.  Zeitschrift  fiir  Pharm.,"  8,  p.  201,  also,  "Canstatt's  Jahresbe- 
richt  fiir  1854,"  p.  76. 
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