no  Biological  Standardization  of  Drugs.  {^'^ix^^^l;^\lu"'' 
experience,  however,  and  after  securing  a  large  number  of  readings, 
all  of  which  may  be  made  on  the  same  organ,  a  fairly  definite 
idea  may  be  obtained  of  the  strength  of  the  drugs,  the  standard 
and  the  unknown. 
As  a  result  of  these  studies  we  have  arrived  at  certain  con- 
clusions basing  them  on  the  comparative  values  obtained  from 
assays  of  a  number  of  commercial  preparations  using  the  five 
methods  outlined  above. 
The  three  biological  methods  showed  a  very  fair  agreement 
while  the  results  from  the  uterus  and  cock's  comb  methods  showed 
an  extraordinary  one.  This  was  a  matter  of  considerable  surprise 
to  us  since  we  had  believed  from  a  rather  limited  experience 
that  the  cock's  comb  method  would  not  give  concordant  results. 
In  this  series  there  appeared  to  be  an  almost  exact  parallelism 
between  these  two  methods  throughout  the  series.  The  blood 
pressure  method  was  generally  concordant  but  in  certain  instances 
showed  a  wide  variation  from  the  results  by  the  other  methods. 
The  two  chemical  methods  did  not  show  any  definite  relation 
to  the  biological  methods  although  there  was  some  agreement. 
The  cornutine  of  Keller  more  closely  paralleled  the  biological 
tests  than  did  the  benzole  extractive  of  Wood,  only  three  of  the 
latter  estimations  in  ii  experiments  corresponding  to  the  rise  in 
blood  pressure. 
Just  how  closely  the  therapeutic  value  of  ergot  corresponds  to 
the  activity  as  expressed  by  these  assays  cannot  be  definitely  deter- 
mined because  of  the  complexity  of  the  chemical  substances  found 
in  this  drug  and  also  because  of  the  variability  in  their  actions. 
There  is  sufiicient  evidence  to  show,  even  if  the  relation  is  not 
an  exact  one,  that  there  is  a  fairly  close  correspondence,  however, 
as  is  evidenced  by  the  surprising  agreement  between  the  results 
by  various  biological  methods.  I  am  also  convinced  as  with 
digitalis  that  the  adoption  of  any  one  of  these  methods  will  result 
in  the  production  of  infinitely  more  uniform  preparations  of  ergot 
than  can  now  be  obtained.  The  limits  of  variation  from  a  given 
standard,  as  a  definite  amount  of  ergotoxine,  would  probably  need 
to  be  fairly  wide,  but  even  with  a  standard  allowing  of  consider- 
able variation  a  great  deal  would  be  gained  for  obstetrical  patients 
who,  as  matters  now  stand,  often  gain  nothing  from  the  administra- 
tion of  this  important  drug  because  of  its  inactivity. 
I  stated  in  the  beginning  as  an  ideal  that  we  should  aim  for 
