ON  COLCHICTA. 
207 
the  corms  depends  in  part  at  least  on  the  presence  of  the  alkaloid 
colchicia. 
In  the  same  Journal,  Vol.  27,  page  539,  is  a  translation  of  a 
very  interesting  account  of  a  case  of  poisoning  by  tinct.  sem. 
colchici,  together  with  some  tests  for  colchicia  reported  by  Dr. 
Casper. 
So  far  as  I  am  informed,  all  those  who  have  published  investi- 
gations on  the  subject  of  colchicum  since  the  time  of  Pelletier 
and  Caventou,  have  selected  the  seeds  to  experiment  on,  and 
have  bestowed  but  little  attention  on  the  corms.  Prof.  K. 
Schroff,  makes  use  of  the  following  language  as  lately  as  the 
middle  of  the  year  1856.  "The  symptoms  of  poisoning  by  the 
fresh  and  dried  bulbs  being  alike  with  those  produced  by  colchi- 
cine, this  principle  is  to  be  regarded  as  the  really  active  principle, 
though  up  to  the  present  time  it  has  not  been  prepared  yet  from 
the  bulb."  (American  Journal  of  Pharmacy,  Vol.  29,  page  324.) 
A  large  number  of  experiments  were  performed  to  discover, 
if  possible,  the  best  method  of  isolating  colchicia.  The  follow- 
ing process  was  found  easy  of  application  and  afforded  a  tolerably 
satisfactory  result.  A  portion  of  dried  English  corms  was  re- 
duced to  coarse  powder,  packed  in  a  displacement  apparatus, 
and  slowly  percolated  with  alcohol  s.  g.  .835  until  nearly  ex- 
hausted. The  resulting  tincture  was  evaporated  by  means  of  a 
water  bath  until  it  assumed  the  consistence  of  a  syrup ;  it  was 
then  poured  into  about  ten  times  its  bulk  of  cold  water  acidulated 
with  acetic  acid  and  strongly  shaken  ;  an  abundant  precipitation 
of  soft  resin  took  place,  which  was  removed  from  the  liquor  by 
straining  through  calico.  The  liquid  was  evaporated  to  about 
one  half  the  bulk  of  the  root  operated  on ;  and,  when  cold,  solu- 
tion of  ammonia  was  added  as  long  as  a  precipitate  was  formed. 
This  precipitate  was  collected  on  a  filter,  strongly  pressed  be- 
tween folds  of  bibulous  paper  to  remove  as  much  as  possible  of 
the  adhering  dark  liquid,  and  then  dissolved  in  absolute  alcohol, 
boiled  with  a  very  little  animal  charcoal,  filtered,  and  evaporated 
at  a  gentle  heat.  The  product  answered  to  the  tests  given  for 
colchicia,  but  it  was  contaminated  with  a  brown  coloring  matter 
difficult  to  remove,  and  contained  a  small  portion  of  a  substance 
which  slightly  modified  its  reaction  with  some  tests. 
