STRYCHNINE  IN  BRITISH  BEER,  PALE  ALE,  ETC. 
173 
hop,  but  very  different  in  kind,  and  easily  distinguished  when  the 
two  bitters  are  compared.  The  bitter  of  the  hop  is  immediate  in 
its  action  upon  the  palate,  is  accompanied  by  a  fragrant  aioma, 
and  soon  passes  off;  while  that  of  strychnine  is  not  so  instan- 
taneous ;  but  when  the  impression  is  once  communicated  it  is  more 
lasting,  and  becomes,  from  its  persistence,  like  that  of  a  metallic 
salt.  The  bitter  of  strychnine  is,  indeed,  easily  distinguishable 
from  that  of  the  hop  when  deliberately  tasted." 
"  Still,  it  would  be  highly  desirable  to  be  able  to  identify  strych- 
nine in  beer  by  the  actual  extraction  of  the  substance,  and  the 
application  to  it  of  a  chemical  test  of  absolute  certainty.  Fortu- 
nately, those  poisons  which  have  the  most  violent  action  upon  Ihe 
animal  economy,  possess  often,  also,  the  best  marked  reactions,  or 
their  physiological  and  chemical  properties  are  equally  salient. 
Thus  arsenic  and  hydrocyanic  acid  are  the  most  easily  detected  of 
chemical  substances,  and  strychnine  proves  to  be  not  far  behind 
them  in  this  respect. 
"  A  quantity  of  strychnine,  not  exceeding  one-thousandth  part 
of  a  grain,  is  tested  and  recognized  to  be  strychnine  in  the  follow- 
ing manner  :  The  powder  is  moistened  with  a  single  drop  of  un- 
diluted sulphuric  acid,  and  a  small  fragment  of  chromate  of  potass 
placed  in  the  liquid.  A  beautiful  and  most  intense  violet  tint  im- 
mediately appears  at  the  points  of  contact,  and  is  speedily  diffused 
over  the  whole  liquid.  Although  most  intense,  the  color  disap- 
pears entirely  again  in  a  few  minutes.  The  admixture  of  the 
smallest  quantity  of  organic  matter,  however,  interferes  with  the 
success  of  the  process.  In  order  to  apply  the  test  in  operating 
upon  a  complex  liquor  like  beer,  the  strychnine  must  first  be  ex- 
tracted from  the  liquid,  and  obtained  in  a  pure,  or  nearly  pure, 
state.  This  difficulty,  which  appears  at  first  considerable,  may  be 
readily  surmounted,  and  the  strychnine,  if  it  really  exists  in  beer, 
be  separated,  and  its  nature  established  in  the  most  certain 
manner. 
"  For  this  pupose,  two  ounces  of  ivory  black,  or  animal  char- 
coal, were  shaken  in  half  a  gallon  of  beer,  to  which  half  a  grain 
of  strychnine  had  been  purposely  added.  After  standing  over 
night,  the  liquid  was  found  to  be  nearly  deprived  of  all  bitterness, 
the  [strychnine  being  absorbed  by  the  charcoal.  The  liquid  was 
now  passed  through  a  paper  filter,  upon  which  the  charcoal  con- 
taining the  strychnine  was  collected  and  drained. 
