2       CHEMICAL  COMPOSITION  OF  GELSEMIUM  SEMPERVIRENS. 
alkaloidal  principle,  which,  being  the  active  principle  of  the 
drug,  may  be  named  gelsemimne,  gelseminia  or  gelsemia. 
It  has  been  known  for  some  years  that  this  drug  contained 
a  very  active  poisonous  principle,  but,  so  far  as  we  are  aware, 
the  only  published  accounts  relating  to  its  chemical  properties 
are  the  two  heretofore  published  in  this  Journal  :  the  first  by 
H.  Kollock,  May  1855;  p.  197,  and  the  other  by  C.  L.  Eberle, 
January,  1869,  p.  35.  Neither  of  these  experimentalists,  how- 
ever, satisfactorily  succeeded  in  isolating  and  ascertaining  the 
chemical  properties  of  this  principle. 
Before  entering  into  the  details  of  the  above  case  of  poisoning, 
the  methods  by  which  the  new  acid  and  base  may  be  obtained, 
together  with  their  respective  chemical  properties,  will  be 
pointed  out. 
I.  Gelseminic  Acid. 
Preparation. — Gelseminic  acid  may  be  obtained  from  the 
fluid  extract  of  gelsemium  by  the  following  method  :  Concen- 
trate the  fluid  extract  on  a  water-bath  to  about  one-eighth  of  its 
volume,  then  add  to  the  concentrated  extract  several  times  its 
volume  of  pure  water  and  allow  the  mixture  to  stand  several 
hours,  or  at  least  until  the  supernatant  liquid  has  become  very 
nearly  or  altogether  clear.  By  this  treatment  most  of  the 
resinous  matter,  held  in  solution  by  the  alcohol  originally 
present,  will  be  separated.  The  mixture  is  then  transferred  to 
a  filter,  the  solids  well  washed  with  water,  and  the  filtrate  thus 
obtained,  together  with  the  washings,  concentrated  on  a  water- 
bath  to  about  the  same  volume  the  concentrated  extract  had 
prior  to  the  addition  of  the  pure  water.  The  concentrated 
liquid,  after  filtration,  if  necessary,  is  acidulated  with  hydro- 
chloric acid  in  the  proportion  of  one  drop  of  the  pure  acid  for 
each  fluid  ounce  of  the  fluid  extract  operated  upon,  then 
thoroughly  agitated  with  about  twice  its  volume  of  ether  ;  after 
the  liquids  have  completely  separated,  the  ethereal  fluid  is  de- 
canted and  the  aqueous  solution  again  agitated  with  a  similar 
quantity  of  ether,  which  in  its  turn  is  decanted  and  the  aqueous 
liquid  finally  washed  with  about  its  own  volume  of  ether. 
On  allowing  the  united  ethereal  liquids  thus  obtained  to  evapo- 
