392 
REMARKS  ON  TJNGUENTUM  MEZEREI. 
liquescent,  and,  which  is  a  test  of  its  purity,  totally  volatilized 
with  decomposition  by  heat,  with  evolution  of  iodine  vapors. 
The  yield  of  several  trials  from  the  above  quantities  was  545 
grains  ;  theoretically  there  should  have  been  576  grains.  Pos- 
sibly the  iodide  of  potassium  employed  was  not  entirely  pure. 
The  collected  and  pure  cream  of  tartar  was  about  700  grains. 
REMARKS  ON  UNGUENTUM  MEZEREI. 
By  Richard  B.  Sheriden. 
(Extracted  from  an  Inaugural  Essay.) 
My  attention  has  been  directed  principally  to  this  preparation, 
on  account  of  the  difficulty  which  every  pharmaceutist  experi- 
ences, in  endeavoring  to  prepare  it  as  directed  by  the  Pharma- 
copoeia. The  objections  to  the  mode  of  preparation  therein  di- 
rected, are  briefly  as  follows  : — 
1.  The  time  required  in  its  preparation,  as,  owing  to  the 
affinity  of  fatty  bodies  for  oxygen,  it  is  impossible  to  keep  lard 
in  a  melted  condition  for  such  a  length  of  time  without  materi- 
ally affecting  the  product. 
2.  The  difficulty  of  bringing  the  bark  to  a  proper  condition  to 
yield  its  virtues  to  the  lard  and  wax  used. 
3.  The  unsatisfactory  appearance  of  the  ointment, 
4.  The  variation  in  strength,  and  consequent  uncertainty  of 
its  operation. 
In  view  of  these  objections,  I  made  experiments  in  order  to 
present  a  more  eligible  formula,  for  the  preparation  of  the  above 
mentioned  ointment. 
Experiment  1.  Four  ounees  of  the  chipped  bark  was  moistened 
with  strong  alcohol,  and  after  standing  48  hours,  was  trans- 
ferred to  a  percolator,  and  alcohol  added  until  the  bark  was  ex- 
hausted. This  tincture  was  evaporated  to  the  consistence  of  an 
extract,  which  weighed  half  an  ounce.  This  was  of  a  brownish 
green  color,  and  possessed  of  the  characteristic  odor  of  the  bark. 
Experiment  2.  An  extract  was  prepared  by  treating  4  ozs.  of 
the  bark  with  ether,  in  the  same  manner  as  in  the  foregoing  ex- 
periment. This  extract  was  of  a  pale  green  color,  and  possessed 
the  same  odor  as  the  alcoholic  extract.    It  weighed  3  drachms. 
