242  Valuation  of  Liquor  Iodi  Compositus.  {Am'££i8OTarm' 
nates  it  as  "  a  clear,  colorless  liquid,  odorless,  having  a  very  acrid 
and  caustic  taste,  and  a  strongly  alkaline  reaction."  "  To  neutral- 
ize 20  grammes  of  solution  of  soda  should  require  about  25  c.c.  of 
normal  sulphuric  acid  (each  c.c.  of  the  volumetric  solution  indicating 
0-2  per  cent,  of  absolute  sodium  hydrate),  phenolphthalein  being 
used  as  indicator." 
The  Pharmacopoeia  recommends  the  solution  to  be  dispensed  in 
the  manner  ordered  for  liquor  potassae.  In  order  to  determine  the 
exact  quality  of  the  article  as  sold  by  manufacturing  pharmacists, 
six  samples  were  purchased  and  examined.  Four  of  these  were  ob- 
tained at  retail  stores  and  two  at  wholesale  houses.  When  the 
samples  were  subjected  to  the  flame  test  for  sodium,  samples  I, 
3  and  6  gave  evidence  of  potassium.  These  behaviors  were  after- 
wards confirmed  by  means  of  the  sodium  cobaltic  nitrite  test. 
Sample  3  was  translucent,  the  other  samples  were  clear.  Samples 
1,3  and  4  had  straw  or  yellow  colors;  the  others  were  colorless. 
Sample  3  was  the  only  one  containing  insoluble  foreign  matter. 
All  were  odorless  and  strongly  alkaline  to  litmus  paper.  No.  3 
contained  calcium.  Carbonate  was  present  in  samples  1,  2,  3  and 
5.  Three  pharmacists  dispensed  the  samples  in  colored  vials.  Two 
of  these  vials  bore  poison  labels. 
Upon  titrating  the  samples  with  decinormal  sulphuric  acid  volu 
metric  solution,  they  were  found  to  range  from  one-half  to  twice  the 
official  strength,  as  follows : 
10-00,4-47,  2-31,  5-25,  4-21  and  4-93  percent. 
VALUATION  OF  LIQUOR  IODI  COMPOSITUS. 
By  Richard  Had  Compton,  Ph.G. 
Contribution  from  the  Chemical  Laboratory  of  the  Philadelphia  College  of 
Pharmacy.    No.  165. 
Lugol's  solution  is  required  by  the  United  States  Pharmacopoeia 
to  be  a  5  per  cent,  solution  of  iodine,  dissolved  in  water  by  the 
addition  of  10  per  cent,  of  potassium  iodide.  The  same  authority 
directs  that  if  "  12  66  grammes  of  the  solution  be  mixed  with  a  few 
drops  of  starch  test  solution,  it  should  require  for  complete  decol- 
oration from  49-3  c.c.  to  50  c.c.  of  sodium  hyposulphite  decinormal 
volumetric  solution  (each  cubic  centimeter  of  the  volumetric  solu- 
tion corresponding  to  o-i  per  cent,  of  iodine)." 
