^mMlyr/imaTm'}P/^rmacopceml  Assays  of  Drugs  and  Galenicals.  227 
The  uncertainty  would  be  considerably  reduced,  though  not  entirely 
removed,  if  an  absolutely  reliable  assay  of  strychnine  could  be 
made;  and  until  this  is  accomplished,  physicians  will  have  to  con- 
tinue to  prescribe  the  alkaloid  strychnine  or  one  of  its  salts,  if  they 
aim  at  producing  definite  effects,  which  they  believe  not  to  be 
obtainable  from  nux  vomica  or  its  preparations  owing  to  the 
inherent  variation  in  their  composition  whether  the  drug  be 
standardized  for  total  alkaloids  or  not.  There  would  be  no  harm 
done  if  the  Pharmacopoeia  would  require,  say  not  less  than  2-5  per 
cent,  of  total  alkaloids  ;.  but  the  necessity  for  it  is  not  apparent 
since  it  will  be  difficult  to  find  in  commerce  nux  vomica  containing 
a  decidedly  smaller  amount.  It  should  also  be  stated  in  this 
connection  that,  in  the  writer's  experience,  the  amount  of  strychnine 
obtained  in  the  manufacture  on  a  tolerably  large  scale,  is  usually 
considerably  less  than  might  be  expected  from  the  figures  given 
above. 
It  seems  unnecessary  to  enter  in  a  similar  manner  into  details 
with  regard  to  other  drugs  containing  alkaloids.  When  examined 
into  without  bias,  it  will  be  found  that  the  different  alkaloids 
present  in  the  same  drug,  if  qualitatively  of  the  same  action, 
usually  differ  considerably  in  their  quantitative  effects  ;  that  not 
unfrequently  the  qualitative  effects  of  such  alkaloids  (for  instance,  in 
aconite,  veratrum,  etc.,)  differ  from  one  another  very  markedly  ; 
and  that  for  both  these  reasons  a  knowledge  of  the  total  amount  of 
alkaloids  cannot  give  a  correct  idea — on  the  contrary,  must  be  fre- 
quently misleading — as  to  the  value  of  such  an  assayed  product 
compared  with  the  effects  of  its  principal  medicinal  alkaloid  in  an 
isolated  condition. 
A  practical  difficulty  for  such  assays  on  the  scale  required  for  the 
pharmacist  consists  in  the  correct  sampling  of  the  drug.  Different 
specimens  of  aconite  root,  of  nux  vomica,  of  the  narcotic  leaves,  etc., 
taken  from  the  same  parcel,  will  be  found  to  give  results  differing 
more  or  less  ;  and  to  preserve  in  several  samples  taken  from  the 
same  lot,  the  relative  proportions  of  old  and  young  roots,  or  of 
rhizomes  and  rootlets  will  prove  to  be  a  most  arduous  task.  In  one 
essay  giving  an  account  of  their  excellent  researches  on  nux  vomica 
(he.  cit.  1884,  p.  463),  Dunstan  and  Short  state  that  "the  alkaloidal 
content  of  the  seeds  is  directly  as  their  size  ar.d  inversely  as  their 
number  in  the  fruit."    These  are  conditions  which  pharmacopceial 
