460     BEST  PART  OF  CONIUM  MACULATUM  FOR  MEDICINE. 
those  of  most  other  medicinal  substances,  and  that  frequently 
these  preparations  are  totally  destitute  of  activity,  we  may  think 
it  worth  our  while  to  inquire  if  there  is  not  some  means  by  which 
such  a  degree  of  uniformity  and  stability  can  be  given  them  as 
to  render  them  worthy  of  the  confidence  and  reliance  of  the 
medical  profession. 
It  was  with  a  view  of  fixing  upon  some  good  plan  for  securing 
this  result,  and  also  with  the  hope  of  adding,  perhaps,  something 
to  the  general  stock  of  knowledge  with  regard  to  the  therapeutic 
uses  of  the  article,  that  the  subject  of  Con  lain  was  accepted  by 
the  writer  for  examination.  In  the  outset  of  the  investigation, 
the  fact  presented  itself  that  pharmacopoeias  differ  a£  to  the  part 
of  the  plant  recommended  for  medicinal  use,  the  U.  S.  Pharma- 
copoeia directing  the  leaves,  and  the  British  the  fruits  or  seeds. 
From  all  that  could  be  gathered  from  the  ordinary  treatises  on 
materia  medica,  it  would  seem  that  the  seeds  are  the  most  active, 
but  how  much  more  energetic  is  not  specified. 
The  first  thing  in  order,  then,  seemed  to  be  to  settle  by  some 
precise  and  accurate  experiments  the  difference,  if  any,  existing 
in  different  parts  of  the  plant  as  respects  their  activity.  As  the 
medicinal  efficacy  of  Conium  is  believed  to  reside  in  the  alkaloid, 
or  alkaloids  existing  in  it,  the  method  of  ascertaining  the  com- 
parative quantities  of  these  alkaloids  that  are  contained  in  differ- 
ent parts  of  the  plant,  presented  itself  as  an  available  one  for 
the  purpose  in  view. 
The  plan  adopted  has  been  to  make,  as  nearly  as  possible, 
precisely  similar  preparations  from  the  leaves  collected  at  two 
different  stages  of  growth,  and  irom  the  seeds  at  different  de- 
grees of  maturity,  and  then  by  a  delicate  re-agent  to  test  their 
comparative  richness  in  the  alkaloids.  The  re-agent  used  was 
that  recommended  by  F.  F.  Mayer,  in  the  American  Journal  of 
Pharmacy,  vol.  xxxv,  p.  23,  consisting  of  a  dilute  solution  of 
iodide  of  potassium  and  corrosive  sublimate  in  water.  As  com- 
parative results  only  were  aimed  at,  the  following  modification 
of  the  course  of  proceeding  prescribed  by  Mayer  was  adopted  : 
The  various  solutions  to  be  tested  were  each  diluted#with  care- 
fully ascertained  amounts  of  water,  till  but  a  faintly  perceptible 
turbidity  was  produced  on  the  addition  of  the  test  liquid,  and 
