228        Pharmaceutical  Notes  from  Pu  rdue  University.  { Am£^Sarm ' 
these  methods  the  time  was  too  short  to  procure  and  test  other  com- 
mercial samples. 
III.     ANTIMONII  ET  POTASSII  TARTRAS.  BY  E.  G.  EBERHARDT. 
Five  commercial  samples,  and  one  of  my  own  preparation  (No.  6), 
were  examined  with  the  following  results.  With  the  exception  of 
No.  2,  which  was  dirty,  all  were  soluble  in  the  prescribed  quantity 
of  water,  showing  the  absence  of  cream  of  tartar  or  oxide  of  anti- 
mony. Nitrate  of  silver  gave  no  reaction  for  chlorides,  and  ferro- 
cyanides  of  potassium  showed  the  absence  of  iron,  etc.  Special  care 
was  taken  in  the  application  of  Fleitrnann's  test  for  arsenic: 
BaCl2-  Am2Ox.  Fleitmann's  Test. 
No.  1  Slight  opalescence.  None.  Trace. 
No.  2  None.  Trace. 
No.  3                      "      \  "  " 
No.  4                                 .  " 
No.  5  Slight  turbidity.  "  Considerable. 
No.  6  None.  None.  Slight  trace. 
We  notice  that  all  contain  arsenic,  but  in  my  opinion  only  No.  5 
contained  objectionable  amounts.  For  the  preparation  of  JNo.  6, 
sulphide  of  antimony,  containing  only  traces  of  arsenic,  was  boiled 
with  hydrochloric  acid  as  usual,  filtered,  boiled  to  expel  sulphuretted 
hydrogen,  and  then  poured  into  water  with  constant  stirring.  Only 
a  small  amount  of  the  arsenic  present  in  the  sulphide  is  dissolved 
and  re-precipitated.  The  oxide,  after  washing  with  water,  was  treated 
with  ammonia  (which  would  tend  to  remove  the  arsenic  still  further) 
before  it  was  dissolved  with  bitartrate  of  potassium;  but  the  phar- 
macopceial  test  is  so  delicate  that  0*0001  per  cent,  of  arsenious  sul- 
phide gives  a  distinct  reaction,  while  O'Ol  per  cent,  makes  a  decided 
black  spjt.  So  rigid  a  test  for  tartar  emetic  seems  needless;  for  the 
far  less  delicate  test  (by  precipitation  of  silver  arsenate)  is  prescribed 
in  the  Pharmacopoeia  for  purified  sulphide  of  antimony,  thus  allow- 
ing considerable  traces  of  arsenic  to  escape  detection  and  be  incor- 
porated with  antimony  pills.1  This  subject  is  further  discussed  in 
the  next  article. 
1  Innry  own  testsof  tartar  emetic  (Proceedings  A. P.  A.  for  lS8o,-pA80), the  paper 
moistened  with  solution  of  silver  nitrate  was  exposed  for  a  few  moments  only 
to  the  escaping  gas,  and  arsenic  was  not  observed.  No  doubt  the  test  is  usually 
applied  with  less  care  than  Mr.  Eberhardt  has  taken.  E.  B.  W. 
