AmA™£:?£^-} Examination  of  Some  Official  Preparations.  183 
AN  EXAMINATION  OF  SOME  OFFICIAL 
PREPARATIONS. 
By  Henry  Trimble. 
Contribution  from  the  Chemical  Laboratory  of  the  Philadelphia  College  of  Pharmacy, 
No.  107. 
It  has  been  the  custom  of  the  author  for  several  years  past  to 
have  students  in  the  laboratory  examine  some  of  the  Pharmaco- 
poeial  preparations.  Last  year  this  work  was  directed  more 
especially  to  the  inexpensive  galenicals  which  are  usually  prepared 
by  the  pharmacist,  although  in  the  following  list  there  are  a  few 
that  are  exclusively  purchased  from  the  manufacturer. 
Tincture  of  Iodine. — Robert'  T.  Ward  purchased  one-half  ounce 
samples  from  the  retail  stores  of  Philadelphia.  The  Pharmacopoeia 
requires  8  per  cent,  of  iodine.  An  assay  of  the  samples  showed 
them  to  vary  from  3-08  to  16-15  per  cent.  Two  were  above  the 
standard  and  23  below.  Nearly  one-half  contained  about  6  per 
cent.  The  sample  containing  16-15  per  cent,  was  dispensed  in  a 
2  drachm  homoeopathic  vial,  without  a  label,  and  was  wrapped  in 
a  circular.  It  was  prepared  while  the  customer  waited,  by  pouring 
an  unknown  amount  of  iodine  into  the  bottle  and  filling  up  with 
alcohol.    The  price  charged  was  10  cents. 
Diluted  Acetic  Acid. — Frank  Miller  procured  20  samples  from 
retail  stores  in  Philadelphia.  With  two  exceptions  they  responded 
fairly  well  to  the  official  tests  of  purity,  but  in  strength  of  absolute 
acid  they  varied  from  i-8o  to  16  20  per  cent.  It  may  be  recalled 
here  that  the  Pharmacopoeia  requires  6  per  cent.  Exactly  one-half 
were  below  the  standard.    The  average  was  6-24  per  cent. 
Sulphurous  Acid. — Clinton  E.  Main  experienced  much  difficulty 
in  obtaining  samples  of  this  preparation.  He  was  in  most  cases 
asked  if  he  did  not  want  sulphuric  acid.  One  clerk  informed  him 
that  sulphurous  acid  was  dispensed  only  on  prescription.  After 
visiting  many  stores  where  it  was  not  kept,  twenty-seven  samples 
were  finally  obtained. 
An  assay  of  each  showed  them  to  vary  from  o-ooi  to  4  02  per 
cent,  of  sulphurous  acid  gas.  The  official  contains  3-5  per  cent,  of 
the  gas.  Twenty-six  of  these  samples  were  below  the  standard 
and  two-thirds  of  them  contained  less  than  one  per  cent. 
Tincture  of  Chloride  of  Iron. — William  A.  Clingan  assayed  14 
samples  of  this  preparation,  purchased  from  retail  stores.  Eleven 
