Am.  Jour.  Pharm. 
July,  1892. 
Assay  of  Nux  Vomica. 
351 
In  a  former  paper1  the  author  suggested  that  fluid  extract  of 
nux  vomica  might  be  standardized  at  1-50  per  cent,  of  natural 
alkaloids,  and  it  will  be  observed  that  the  average  of  this  series  of 
determinations  makes  it  1-59.  Nine  of  the  samples  exceeded 
that  valuation  (1-50),  thus  establishing  the  fact  that  should  the 
pharmacopceia/equire,  a  higher  standard  could  be  accepted  or  at 
least  attained  by  manufacturers. 
Of  the  thirteen  specimens  examined,  one  only  contained  a  state- 
ment on  the  label  concerning  its  alkaloidal  extractive  value.  A,  of 
the  list,  stated  that  the  alkaloidal  percentage  was  2-36  per  cent.,  and 
the  extractive  13-8  per  cent.  For  this  reason,  this  specimen  was 
selected  for  further  consideration. 
(9)  Total  Extractive  (Variation)  of  Specimen  A. — The  maker  of 
this  specimen  established  on  the  label  the  extractive  valuation  of 
13-8  per  cent.  Careful  investigations  demonstrated  that  in  our 
hands,  as  conditions  varied,  the  extractive  might  range  from  11-95 
*°  1 5*35  Per  cent. 
By  measure,  2-5  cc.  evaporated  in  the  drying  room  at  1400  F. 
and  then  exposed  for  four  hours,  left  0-322  gm.  of  residue  which  in 
twelve  hours  was  reduced  to  0-309  gm. 
One  gm.  evaporated  in  a  large  flat  bottomed  dish  on  a  steam  bath 
left  15-35  Per  cent.,  and  then  exposed  in  a  dry-room  for  one  hour 
left  15-1  per  cent.,  and  after  six  hours'  exposure  with  occasional  stir- 
ring, 1 1  95  per  cent,  remained.  This  residue  submitted  to  open 
laboratory  air  for  ten  minutes  increased  to  12  95  per  cent.,  and  still 
continued  to  increase.  An  average  of  the  results  is  13  84  per  cent, 
which  is  remarkably  near  the  valuation  (13  8  per  cent.)  of  the  manu- 
facturer. However,  it  will  be  observed  that  under  conditions  that 
might  be  considered  unimportant,  the  same  residue  altered  materially 
in  weight,  enough  to  cause  considerable  discrepancies  in  different 
assaying  reports,  were  different  operators  not  working  under  exactly 
similar  conditions.  In  my  opinion  allowances  for  sucl  disturbances 
must  be  made  in  these  lines  of  observation,  and  exact  comparisons 
cannot  be  consistently  drawn  unless  details  often  unmentioned  by 
operators  are  recorded.  That  extremely  close  work  is  unnecessary, 
however,  at  this  date,  will  probably  be  accepted,  if  any  galenicals 
are  standardized,  for  even  approximate  alkaloidal  requirements  (see 
Proceedings  Am.  Pharm.  Assoc.,  1891,  p.  129. 
