USE  OP  YELLOW  WAX  IN  OINTMENTS. 
59 
necessary  ;  evaporate  to  the  consistency  of  a  thick  syrup  ;  paint 
on  glasses  and  scale  as  usual.  The  change  which  takes  place  on 
the  addition  of  the  ammonia  is  different  from  the  appearance 
produced  by  the  addition  of  citrate  of  ammonia  solution. 
In  the  case  of  the  addition  of  aqua  ammonise,  the  magma 
turns,  in  a  few  hours,  of  brick-red  color ;  and  in  the  case  of  the 
addition  of  citrate  of  ammonia  solution,  it  dissolves  to  a  green 
color,  similar  to  the  iodide  of  iron  liquor,  before  adding  the 
syrup. 
If  now  you  add  the  citric  acid  to  the  brick-red  colored  mag- 
ma, it  gradually  dissolves  and  becomes  a  greenish  color  by 
transmitted  light,  and  dark-brown,  almost  black,  when  concen- 
trated, by  reflected  light. 
That  there  is  a  different  apportioning  of  elements  produced 
by  the  modification  no  one  can  deny.  In  the  first  you  have 
pyrophosphate  of  iron  in  solution  by  means  of  citrate  of  am- 
monia, a  mixture  of  neutral  salts.  In  the  second  you  have,  on 
the  addition  of  ammonia,  pyrophosphate  of  ammonia  and  ses- 
quioxide  of  iron,  which  latter  exists  in  a  free  state.  On  the 
addition  of  the  citric  acid  it  unites  with  the  sesquioxide  of  iron, 
forming  the  citrate  of  the  sesquioxide  mixed  with  the  phosphate 
of  ammonia.  I  think  from  this  it  will  be  seen  that  the  com- 
position is  changed,  the  iron  in  the  Pharmacopoeia  formula 
(Squibb's,)  existing  as  a  pyrophosphate ;  the  iron  in  my  modifi- 
cation existing  as  a  citrate  of  the  sesquioxide. 
As  the  Pharmacopoeia  Committee  consider  their  preparation 
an  intimate  admixture  of  ferruginous  and  ammoniacal  salts,  I  do 
not  consider  I  have  violated  the  U.  S.  P. 
Detroit,  Aug.  5,  1868. 
— Proc,  Amer.  Pharm.  Assoc. ^  1868. 
ON  THE  USE  OF  YELLOW  WAX  IN  OINTMENTS. 
By  Ferris  Bringhurst. 
Query  35. — It  has  been  asserted  that  yellow  wax  is  better  than 
bleached  wax  for  the  preparation  of  Ceratum  and  Unguentum  adipis. 
If  this  be  true,  what  principle  in  the  crude  wax  possesses  this  property, 
and  for  what  extent  of  time  may  its  conservative  power  be  relied  on  ? 
