564  Some  Pharmacopceial  Problems.  {ADecimbe^hi899?' 
often  overlooked.  It  is  manifestly  insufficient  merely  to  determine 
the  amount  of  alkaloidal  or  other  active  substance  present,  particu- 
larly in  the  case  of  preparations  made  from  expensive  drugs,  unless 
it  is  shown  that  the  separated  principle  is  unaccompanied  by  matters 
foreign  to  the  drug,  such,  for  instance,  as  some  cheap  foreign  alka- 
loid that  might  have  been  added  to  bring  out  a  favorable  "  assay." 
While  this  feature  (the  identification)  is  quite  important  in  actual 
practice,  it  can  be  disregarded  in  the  Pharmacopoeia,  since  the 
latter  generally  directs  to  start  a  preparation  from  the  drug  itself, 
about  the  identity  of  which  there  can  be  no  question. 
(3)  Adjustment  of  Strength. — This  is  the  final  end  and  aim  of 
"  standardization."  It  is,  of  course,  comparatively  easy  to  standard- 
ize the  preparations  of  any  drug,  the  active  principle  (or  princi- 
ples) of  which  can  be  correctly  determined  quantitatively.  It  will 
merely  be  necessary  to  agree  upon  some  definite  strength  or  upon 
an  upper  and  lower  limit  of  the  active  principles.  Of  course, 
standardization  need  be  applied  only  to  drugs  of  importance  and 
potency.  There  is  no  need  of  standardizing  preparations  Of  gen- 
tian, quassia,  sarsaparilla,  squill,  senna,  etc.,  even  if  it  were  possi- 
ble in  each  case  to  do  this. 
But  there  are  some  drugs  which,  with  our  present  knowledge,  it 
is  not  possible  to  standardize  in  the  sense  above  mentioned.  One 
of  these  is  Ergot.  It  is  claimed  by  some  that  its  physiological 
action  is  due  to  Keller's  u  cornutine,"  and  some  manufacturers 
assay  it  and  standardize  it  on  the  basis  of  this  alkaloid.  But  it  is 
not  by  any  means  certain  that  other  principles  in  ergot  do  not  par- 
ticipate in  its  peculiar  action.  Another  case  in  point  is  Digitalis. 
We  know  that  digitoxin  is  the  most  active  of  the  cardiac  principles 
it  contains.  But  there  is  no  certainty  as  yet  that  it  is  the  only  one 
that  should  be  considered.  If  we  knew  for  certain  that  the  propor- 
tion of  digitoxin  to  the  other  principles  present  in  digitalis  were  at 
all  times  the  same,  we  could  accept  it  as  a  measure  to  gauge  the 
activity  of  digitalis  by.  But  even  this  point  is  not  cleared  up. 
And  our  experience  with  other  drugs  makes  it  likely  that  the  pro- 
portion between  the  various  principles  of  digitalis  varies  more  or 
less  at  different  times.  Strophantlms  may  be  mentioned  as  another 
drug  for  which  we  have  no  practical  assay  process.  Realizing  these 
facts,  and  yet  desiring  to  give  to  their  customers  reliable  prepara- 
tions, some  of  the  larger  manufacturing  houses  have  adopted  the 
