40     REMOVAL  OF  ODOROUS  COMPOUNDS  FROM  ALCOHOL,  ETC. 
cent,  of  alcohol,  was  clear,  colorless,  and  possessed  a  faint  odor 
of  the  sarsaparilla  compound.  It  certainly  was  clean  enough  to 
be  used  in  many  Galenical  preparations.  The  writer  has  often 
seen  poorer  samples  of  alcohol  in  the  market. 
Exp.  3. — Five  pints  of  impure  alcohol  were  obtained,  half  from 
fl.  ext.  senna,  half  from  fl.  ext.  senega.  The  mixture  contained 
85  per  cent.  (Tralles)  of  alcohol ;  had  a  very  decided  odor  of 
senna. 
Exp.  4. — The  above  mixture  was  re-distilled  with  100  grs.  of 
permanganate  of  potassa  previously  dissolved  in  f^i  of  water. 
The  distillation  was  stopped  when  four  and  three-fourths  pints  of 
distillate  were  obtained ;  this  was  clear,  colorless,  contained  84 
per  cent,  of  alcohol,  and  was  to  a  very  great  extent  deprived  of 
the  odor  of  senna ;  more  clean  than  No.  2. 
Exp.  5. — Five  pints  of  unclean  alcohol  of  67  per  cent,  proof, 
from  fl.  ext.  scullcap  ;  odor  strong  of  scullcap. 
Exp.  6. — No.  5,  with  100  grs.  of  permanganate  of  potassa, 
was  re-distilled,  and  distillation  stopped  when  four  pints  of  dis- 
tillate had  been  obtained.  This  was  clear,  bright,  77  per  cent, 
alcohol,  and  much  improved  by  the  treatment  with  permanga- 
nate. 
Exp.  7. — Five  pints  of  alcohol  from  fl.  ext.  wild  cherry,  with 
100  grs.  permanganate  of  potassa.    Product  very  clean. 
Exp.  8. — Four  fluid-ounces  of  tinct.  of  buchu  were  treated 
with  200  grs.  of  permanganate  of  potassa,  dissolved  in  water 
and  filtered.  By  this  treatment  it  was  in  a  great  measure  de- 
prived of  odor  and  also  of  color,  as  may  be  seen  by  comparing 
the  samples  of  the  tincture  before  and  after  the  treatment  with 
permanganate. 
Exp.  9. — Three  pints  of  impure  alcohol  recovered  from  the 
tincture  of  buchu  used  in  No.  8  were  re-distilled  with  500  grs.  of 
manganate  of  potassa  (common  permanganate  of  commerce)  and 
two  and  one-half  pints  of  distillate  obtained.  This  smelled  of 
the  buchu  nearly  as  much  as  the  tincture  that  was  simply  treated 
with  permanganate  without  distillation. 
From  these  experiments  the  writer  concludes  that  the  rectifi- 
cation of  unclean  alcohol  with  small  quantities  of  permanganate 
