434  Relative  Value  of  Colchicum  Root.     { AmseJpT'x87h7arm 
The  tinctures  obtained  were  separately  evaporated  by  means  of  a 
water  bath,  the  residue  was  treated  with  distilled  water,  and  poured 
upon  a  filter,  in  order  to  separate  resinous  matter  ;  the  filtrate  was 
washed  with  slightly  acidulated  water  until  each  filtrate  measured  100  cc. 
Dilute  sulphuric  acid  was  used  for  acidulating  the  solutions,  which  were 
volumetrically  tested  with  Mayer's  solution,  in  quantities  varying  from 
5  to  15  cc.  In  the  preliminary  experiments  the  solutions  were  variously 
diluted,  and  it  was  observed  that  the  results  were  very  considerably 
influenced  thereby,  an  observation  previously  made  by  DragendorfF. 
To  serve  as  a  basis  for  comparison,  the  experiments  were  afterwards 
made  with  solutions  of  uniform  strength,  as  stated  above,  partly  without 
any  other  addition,  and  partly  as  recommended  by  DragendorfF,  after 
the  addition  of  a  concentrated  solution  of  chloride  of  sodium,  to  increase 
the  distinctness  of  the  reaction.  The  three  grades  of  the  root  required 
for  1  cc.  respectively  '0403,  '0414  and  '0462  of  Mayer's  solution. 
Five  troyounces  of  each  of  the  roots  were  next  exhausted  by  alcohol, 
percolation  in  each  case  being  carried  on  until  the  liquid  passed  tasteless. 
The  alcohol  was  evaporated,  and  the  residues  were  treated  with  water, 
filtered  and  precipitated  by  a  solution  of  tannin.  These  tannates  of 
the  white,  gray  and  black  roots,  which,  after  having  been  dried^  weighed 
respectively  '32,  '265  and  '2J  gram,  were  decomposed  by  oxide  of  lead, 
and  then  treated  with  alcohol,  in  order  to  separate  colchicia.  The 
three  alcoholic  solutions  were  carefully  evaporated  to  dryness,  then 
placed  over  sulphuric  acid  for  several  days,  and  then  their  weight  taken  ; 
the  product  from  the  gray  root  weighing  '115  gram,  the  black  yielding 
•104  gram,  while  the  product  from  the  white  root  was  unfortunately 
lost. 
I  next  obtained  same  colchicum  root  from  Professor  Maisch,  which 
was  not  less  than  ten  years  old,  it  having  been  in  his  possession  at  least 
nine  years.  It  had  quite  a  handsome  appearance,  very  little  dark  root 
being  present,  and  in  all  respects  was  a  much  better  looking  article  than 
that  previously  employed.  Two  troyounces  of  this  root  were  treated 
as  stated  above,  and  an  acid  solution  obtained,  measuring  100  cc,  and 
which,  when  treated  with  Mayer's  test,  in  a  similar  manner  as  before, 
required  '0300  for  the  precipitation  of  1  cc. 
The  various  results  thus  obtained  are  more  concisely  presented  in 
the  following  table  : 
