Am.  Jour.  Pharm. 
April,  1917. 
Determination  of  Phenacetin. 
155 
is  complete,  transfer  the  filter  paper  and  residue  to  the  beaker,  add 
25  mils  of  hot  distilled  water  to  dissolve  the  milk  sugar;  transfer 
this  solution  to  a  100  mil  volumetric  flask,  wash  the  filter  paper  and 
beaker  with  more  water  until  the  collected  washings  total  100  mils. 
Cool  to  room  temperature  and  add  water  to  the  100  mil  mark. 
Portions  of  this  aqueous  solution  corresponding  in  volume  to  the 
amounts  used  in  the  standard  tubes  are  measured  into  Nessler  tubes 
and  treated  exactly  like  the  standards. 
Standards  are  prepared  as  follows  : 
Dissolve  .500  g.  of  milk  sugar  in  sufficient  water  to  make  100 
mils ;  one  mil  of  this  solution  contains  .005  g.  of  milk  sugar. 
Tube4  A  —  1  mil  of  st.  sol.  =  (.005  g.  milk  sugar)  +4  mils  of  water -j- 10 
mils  of  cone,  ammonium  hydroxide. 
Tube  B-\-2  mils  of  st.  sol.  =  (.010  g.  milk  sugar)  -f- 3  mils  of  water -|- 10 
mils  of  cone,  ammonium  hydroxide. 
Tube  C-f-3  mils  of  st.  sol.  =  (.015  g.  milk  sugar)  -j-  2  mils  of  water  +  10 
mils  of  cone,  ammonium  hydroxide. 
Tube  D-f-4  mils  of  st.  sol.  =  (.020  g.  milk  sugar)  1  mil  of  water  +  10 
mils  of  cone,  ammonium  hydroxide. 
Tube  E 5  mils  of  st.  sol.  =  (.025  g.  milk  sugar)  -[-  10  mils  of  cone,  ammo- 
nium hydroxide. 
These  tubes  as  well  as  those  containing  the  unknown  are  placed 
in  a  water  bath  and  heated  to  about  95 0  C.  for  about  half  hour,  the 
volume  in  each  tube  is  then  made  to  50  mils  and  allowed  to  stand  5 
minutes.  The  depth  of  color  produced  in  the  tubes  containing  the 
sample  is  compared  with  the  standards  until  two  are  found  (one 
standard  and  one  unknown)  that  correspond.  Computations  are  then 
made  from  the  standard  tube. 
Chemical  Laboratory, 
Department  of  Health,  City  of  New  York. 
APPROXIMATE    DETERMINATION    OF  NOVASPIRIN, 
ALONE  OR  WHEN  MIXED  WITH  ASPIRIN. 
By  Reginald  Miller. 
This  method  depends  upon  the  fact  that  sodium  hydrate  produces 
a  yellow  color  with  novaspirin  but  remains  colorless  with  aspirin.1 
4  Nessler  tubes  holding  100  mils  are  used. 
1  The  aspirin  must  not  be  present  in  a  greater  proportion  than  two  parts 
of  aspirin  to  one  part  of  novaspirin,  if  present  in  a  larger  amount,  it  inter- 
feres with  the  production  of  the  yellow  color. 
