DETECTING  THE  ORGANIC  ALKALOIDS  IN  CASES  OF  POISONING.  53 
exists  in  the  suspected  matter  under  analysis.  To  extract  the 
alkaloid  from  the  solution  of  the  acid  sulphate,  we  add  to  the  latter 
an  aqueous  and  concentrated  solution  of  potash  or  caustic  soda,  we 
agitate  and  exhaust  the  mixture  with  pure  ether;  the  ether  dissolves 
ammonia,  and  the  alkaloid  is  now  free.  We  expose  the  ethereal 
solution  at  the  lowest  possible  temperature  to  spontaneous  evapora- 
tion; almost  all  the  ammonia  volatilizes  with  the  ether,  whilst  the 
alkaloid  remains  as  residue.  To  eliminate  the  last  traces  of  am- 
monia, we  place  for  a  few  minutes  the  vessel  containing  the  alkaloid 
in  a  vacuum  over  sulphuric  acid,  and  obtain  the  organic  alkaloid 
with  the  chemical  and  physical  characters  which  belong  to  it,  and 
which  it  is  now  the  Chemist's  duty  to  determine  positively. 
I  applied,  on  the  3d  of  March,  1851,  the  process  which  I  have 
described,  to  the  detection  of  nicotine  in  the  blood  from  the  heart 
of  a  dog  poisoned  by  two  cubic  centimetres  [0.78  C.I.]  of  nicotine 
introduced  into  the  oesophagus,  and  I  was  able  in  a  most  positive 
manner  to  determine  the  presence  of  nicotine  in  the  blood.  I  was 
able  to  determine  its  physical  characters  ;  its  odor,  taste,  and 
alkalinity.  I  succeeded  in  obtaining  the  chloro-platinate  of  the 
base  perfectly  crystallized  in  quadrilateral  rhomboidal  prisms  of  a 
rather  dark  yellow  color,  and  to  ascertain  their  insolubility  in 
alcohol  and  ether. 
I  have  applied  the  same  process  for  the  detection  of  conia  in  a 
very  old  tincture  of  hemlock,  which  my  friend  and  colleagueM.de 
Hemptinne  was  so  kind  as  to  put  at  my  disposal  ;  and  I  was  equally 
successful  in  extracting  from  the  liquid  colorless  conia,  presenting 
all  the  physical  and  chemical  properties  of  this  alkali.  I  was  also 
able  to  prove  that  the  ether  which  holds  conia  in  solution,  carries 
off  a  notable  portion  of  this  alkaloid  when  the  solvent  is  exposed 
to  spontaneous  evaporation. 
Examination  for  a  Solid  and  Fixed  Alkaloid. 
Let  us  now  suppose  that  the  alkali  is  solid  and  fixed  ;  in  that 
case,  according  to  the  nature  of  the  alkali,  it  may  happen  that  the 
evaporation  of  the  ether  resulting  from  the  treatment  of  Ihe  acid 
matter,  to  which  we  have  added  bicarbonate  of  soda,  may  leave  or 
not  a  residue,  containing  an  alkaloid.  If  it  does,  we  add  a  solution 
of  caustic  potash  or  soda  to  the  liquid,  and  agitate  it  briskly  with 
ether.    This  dissolves  the  vegetable  alkaloid,  now  free  and  re- 
5* 
