5 18  Alkaloids  and  Alkaloidal  Drugs.     {November  Am^' 
in  composition,  hydrastine  hydriodide  pentaiodide,  as  determined 
by  a  preparation  and  analysis  as  described  in  previous  papers.1 
Calculated  for  Found. 
C21H21N06HI.I6.           I.  II. 
Additive  iodine  55-43  55-30  55-34 
Total  iodine  66*52  66  86  66 '06 
The  lower  periodide  of  hydrastine,  formed  when  the  iodine  solu- 
tion is  added  to  the  alkaloidal  salt  solution,  is  from  light  brown  to 
dark  broWn  in  color.  It  is  not  constant  in  composition,  and  was 
only  obtained  as  an  approach  to  a  triiodide.  Prepared  and  analyzed, 
it  gave  figures  as  follows : 
Calculated  for  Found. 
C2iH2iN06HI.l2.  I.  II.                III.  •  IV. 
Additive  iodine  .  .33*22  3576  36-07         36*33  36*02 
Total  iodine    .  .  .  49*83  50*01  4974           —  — 
IODOMETRIC  ESTIMATION  OF  HYDRASTINE.2 
The  exclusive  formation  of  the  hexiodide  is  insured  by  slowly 
adding  a  weak  alkaloidal  solution  to  a  large  excess  of  the  iodine 
solution,  and  proceeding  as  directed  for  other  iodometric  estima- 
tions.3 The  iodine  factor  for  hydrastine  is  0  60403  (382-14  :  5  x 
126*53  :  :  0*60403  :  1).  This  factor  was  verified  in  the  estimation 
of  solutions  of  0*3  per  cent,  and  of  015  per  cent,  of  hydrastine. 
ASSAY  OF  HYDRASTIS. 
Ten  grammes  of  the  finely  powdered  hydrastis  are  rubbed  up  to 
a  paste  with  a  few  cubic  centimetres  of  a  mixture  of  alcohol  and 
stronger  ammonia,  each,  5  ex.,  and  ether,  30  c.c,  in  an  8-ounce 
screw-top  ointment  jar,  and  a  few  cubic  centimetres  more  of  the 
same  mixture  are  then  added,  so  as  to  have  the  powder  well  cov- 
ered with  liquid.  The  small  pestle  is  then  left  inside,  and  the  jar, 
well  covered,  is  set  aside  over  night.  The  jar  is  then  opened,  put 
into  a  good  current  of  air  till  the  odor  of  ammonia  has  disappeared, 
and  then  in  a  vacuum  over  sulphuric  acid  for  about  five  or  six 
1  "  Proc  Amer.  Pharm.  Assoc.,"  1898,  pp.  358,  364. 
2  We  are  indebted  to  Prof.  John  U.  Iyloyd  for  a  specially  prepared  sample 
of  hydrastine.  We  had  also  a  sample  in  a  lot  of  pure  alkaloids  furnished  by 
Merck  &  Co.,  and  the  latter  agreed  very  well  with  the  former  in  the  quantita- 
tive results. 
3  See  an  accompanying  paper,  "Directions  for  Alkaloidal  Assays,"  AMER. 
Jour.  Pharm.,  1899,  p.  462. 
