POISONOUS  DYES. 
367 
of  which  had  ulcerated  ;  and  she  suffered  from  giddiness  and 
severe  pains. 
Tardieu,  assisted  by  M.  Roussin,  submitted  the  socks  worn  by 
the  first  patient  seen  by  him  to  a  careful  examination.  They 
were  treated  by  boiling  alcohol,  in  which  the  red  coloring  matter 
quickly  dissolved.  This  alcoholic  solution,  evaporated  to  dry- 
ness, yielded  an  extract  of  which  the  poisonous  properties  were 
proved  by  the  experiments  now  to  be  described. 
The  dry  coloring  matter,  redissolved  in  a  small  quantity  of 
alcohol,  was  injected  under  the  skin  of  the  thigh  of  a  dog,  a 
rabbit,  and  a  frog.  The  three  animals  died ;  the  frog  the  same 
day,  after  .four  hours  ;  the  dog  the  next  day,  after  having  sur- 
vived thirty-six  hours  ;  the  rabbit  not  till  the  day  following. 
The  dog  and  the  rabbit  had  excessive  and  incessant  evacua- 
tions. The  experimenters  then  determined  to  try  the  coralline 
itself.  In  order  to  obtain  it,  they  applied  to  M.  Persoz,  jun., 
who  discovered  it  in  the  year  1860,  and  who  placed  at  their  dis- 
posal three  specimens  :  the  first  a  pure  coralline,  the  second  the 
red  coralline  of  commerce,  the  third  the  yellow  coralline.  The 
coralline,  or  peonine,  is  obtained  from  rosolic  acid,  which  is  itself 
a  derivative  by  oxidation  from  phenic  acid.  It  is  formed  in  a 
close  vessel,  heated  to  150  degrees,  by  the  contact  of  rosolic  acid 
and  ammonia.  The  result  is  a  solid  matter,  in  plates,  of  a 
poppy-red  color,  green,  or  dull  yellow,  by  reflected  light,  nearly 
insoluble  in  water,  soluble  in  alcohol  and  oils,  and  which  has  all 
the  characters  of  an  amidic  acid. 
A  quantity  of  the  alcoholic  solution  containing  2|-  grains  of 
solid  coralline  was  injected  under  the  skin  of  a  dog  of  medium 
size.  The  next  day,  and  the  day  after,  it  was  dispirited  and 
depressed,  suffered  from  well-marked  intestinal  derangements 
and  loss  of  appetite,  and  the  thigh  near  the  seat  of  the  injection 
had  become  painful.  The  animal  showed  signs  of  suffering,  and 
walked  lame.  The  fourth  day  a  quantity  equivalent  to  3  grains 
of  coralline  was  injected.  The  symptoms  reappeared  almost 
immediately,  the  alvine  evacuations  returned,  the  weakness  con- 
tinued to  increase,  the  fever  grew  more  and  more  intense,  and 
the  pain  in  the  thigh  became  more  acute.  The  animal  trembled 
and  could  not  support  itself,  its  eye  grew  dim,  and  it  died  the 
