'^Ta^aryHs™  }     Emetine  Octoiodide  and  Alkaloids.  21 
Glenard,15  C30  H44  N2  04  =  494-96. 
Kunz,16  C30  H40  N2  05  —  506-92. 
Paul  and  Cownly,17  C15  H22  N  02  =  247-48. 
Our  periodide  corresponds  best  to  the  formula  of  Lefort  and 
Wurz. 
It  seems  to  be  emetine  hydriodide  heptaiodide,  C28H40N2O5 .  HI^. 
For  the  estimation  of  the  additive  iodine  the  periodide  is  dis- 
solved in  chloroform  mixed  with  alcohol  and  titrated  with  standard- 
ized sodium  thiosulphate,  using  starch  as  indicator.  It  is  best  to 
add  first  an  excess  of  the  thiosulphate  solution,  then  add  considera- 
ble water,  when  the  excess  is  titrated  back  with  standardized  iodine. 
For  the  total  iodine  the  periodide  is  dissolved  in  a  little  chloroform 
mixed  with  a  few  drops  of  alcohol ;  powdered  zinc  is  then  added, 
and  the  mixture  kept  on  a  water  bath  till  effervescence  (from  the 
action  of  zinc  on  the  chloroform)  ceases.  To  the  mixture  when 
cold  ammonia  water  is  added  and  the  iodine  in  the  zinc  and  ammo- 
nium iodide  is  estimated  exactly  as  described  in  the  analysis  of 
morphine  tetraiodide.18 
For  additive  iodine  0-1492  gram  of  the  periodide  gave  0-0880045 
iodine,  and  01 22  gave  0-072725  iodine. 
Calculated  for 
C28H40N2O5  .  HIJ,.  Found. 
(I)  •   •   59"24  59'9S 
(2J   59'24  59"61 
For  total  iodine  013  13  of  the  periodide  gave  0-0890502  iodine  ; 
and  0-12095  gave  0-0818797  iodine. 
Calculation  for 
C2SH40N2O5  .'HIJ,.  Found. 
(1)   •     •     ,  ,     .      67-69  67-82 
(2)  ^    67-69  67.69 
Chemical  Laboratory  of  the  University  of  Michigan, 
November  6,  1898. 
15  Ann.  Chim.  Phys.  (5)  8,  233. 
16  Arch.  d.  Pkarm.,  225  (1887)  461-232,  (1894)  466. 
17  Pkarm.  J.  (3)  XXIV.  6  r .  t 
18/.  Am.  Chem.  Soc,  189S,  XX,  717. 
Ammoniacal  Collodium  for  Insect  Stings  is  prepared  {Sudd.-Apoth.-Zeit., 
1898,  614  from  Butt,  gen  de  Therap.)  as  follows  :  Liquor  ammon.  caust.  4ogtt. ; 
collodii,  3  0  gm.;  acidi  salicylici,  0*3  gm.  A  few  drops  of  this  solution  are 
applied  to  the  place  where  the  sting  has  occurred. 
