ON  COLCHICIN. 
105 
istics,  with  an  analysis,  in  which  two  new  alkaloids  are  announced  ; 
and  a  brief  account  of  a  new  kind  of  Rhatany,  (Krameria  cistoi- 
dea,)  from  Chili,  said  to  be  equal  to  the  commercial  article,  by 
Isidro  Salinas. 
ON  COLCHICIN. 
By  MM.  Ludwig  and  Hubler. 
In  the  Journal  de  Pharmacie  for  December,  1865,  is  a  con- 
dense^! paper  embodying  the  chief  points  in  the  essays  of  the 
authors,  which  were  published  in  Arch,  der  Pharm.,  t.  cxi.,  p.  10 
and  194.  Both  chemists  employed  the  seed  of  colchicum.  M. 
Ludwig  confirmed  the  statements  of  Oberlin,  (see  Vol.  xxix., 
p.  235,  of  this  Journal).  M.  Hubler  does  not  appear  to  have 
met  with  the  essay  of  John  E.  Carter,  published  in  Vol.  xxx., 
p.  205,  of  the  American  Journal  of  Pharmacy,  but  adopts 
almost  precisely  the  same  method  as  that  writer ;  who,  however, 
operated  on  the  corms,  and  not  on  the  seeds,  and  obtained  a 
well-marked  amorphous  alkaloid.  M.  Hubler  treated  the  seeds 
(without  bruising,  which  he  thinks  unnecessary,)  with  hot  alcohol 
of  90  per  cent.,  added  to  the  tincture  [probably  after  removing 
the  alcohol]  twenty  times  its  volume  of  water  to  separate  fixed  oil, 
filters  and  precipitates  with  subacetate  of  lead  to  remove  coloring 
matter,  and  by  phosphate  of  soda  to  separate  the  excess  of 
lead,  and  finally  with  tannin  to  precipitate  the  colchicin.  Pure 
tannin  should  be  used,  and  its  addition  should  be  fractioned,  so 
as  to  collect  the  first  and  last  precipitates  separately,  as  less 
pure  than  the  rest.  This  precipitate  consists  of  three  equiva- 
lents of  colchicin  and  two  equivalents  of  tannin,  and  is  very 
soluble  in  alcohol  and  insoluble  water.  It  is  pressed  and  tritu- 
rated with  hydrated  oxide  of  lead,  until  a  little  of  it,  washed 
with  water,  affords  no  coloration  with  sesqui-salts  of  iron.  The 
colchicin  is  separated  by  boiling  alcohol,  and,  after  evaporation, 
finally  dried  over  sulphuric  acid  in  a  vacuum. 
Colchicin  thus  obtained  is  amorphous,  soluble  in  water  and 
alcohol  without  residue,  has  an  odor  like  hay,  more  evident 
when  in  hot  water,  and  is  very  bitter.  It  represents  the  poi- 
sonous principle  of  colchicum.  Without  action  on  test  papers, 
its  solutions  are  precipitated  yellow  by  chloride  of  gold,  and 
white  by  corrosive  sublimate.    The  mineral  acids,  as  well  as  the 
