AmkJp°rnr;ffirm-}    Nitrates  and  Ammonia  in  Water.  157 
The  point  to  be  observed  is  to  procure  an  article  of  good  quality, 
as  the  color  of  the  finished  syrup  is  influenced  thereby.  The  follow- 
ing formula  can  be  quickly  manipulated  and  furnishes  a  syrup 
equal  to  that  of  the  1 870  Pharmacopoeia.  When  first  prepared,  it  is 
somewhat  cloudy,  soon  becoming  clear,  but  does  not  possess  the 
brilliant  transparency  of  the  official  syrup. 
SYRUPUS  ACACIA. 
Acacia,  granulated   8*5  grammes. 
Sugar  20  " 
Distilled  water  25  c.c. 
Syrup,  a  sufficient  quantity  to  make  .  .  .  .  .  .  .  .  .  100  c.c. 
Mix  the  sugar  with  the  acacia  and  add  to  the  distilled  water, 
previously  warmed  in  a  capsule. 
Stir  until  dissolved,  continuing  a  gentle  heat.  Finally  add  a  suffi- 
cient quantity  of  syrup  to  make  the  syrup  measure  100  c.c. 
It   
THE  ESTIMATION  OF  NITRATES  AND  AMMONIA  IN 
WATER. 
By  Frank  X.  Moerk. 
Read  at  the  Pharmaceutical  Meeting  of  the  Philadelphia  College  of  Pharmacy, 
March  21,  1899. 
The  quantities  of  chemicals  which  have  to  be  determined  in  water 
analyses  are,  as  a  rule,  so  minute,  that  the  employment  of  the  usual 
methods  of  quantitative  analysis  means  the  evaporation  of  large 
quantities  of  the  samples  to  obtain  suitable  quantities  of  residue, 
hence,  it  is  not  surprising  that  within  recent  years  delicate  colori- 
metric  tests  have  largely  been  made  use  of,  particularly  in  the  esti- 
mations of  the  heavier  metals  and  of  the  nitrogen-containing  com- 
pounds like  the  nitrites,  nitrates  and  the  free  and  albuminoid 
ammonia. 
ESTIMATION  OF  NITROGEN  AS  NITRATES. 
The  method  generally  used,  depends  upon  the  formation  of  aro- 
matic nitro-derivatives,  which  have  intense  coloring  power,  espe- 
cially in  alkaline  solutions  ;  the  manipulation  used  by  the  writer  for 
some  years  is  as  follows :  10  c.c.  of  the  sample  are  evaporated  to 
dryness  in  a  small  porcelain  capsule  on  a  water-bath  ;  the  resi- 
due is  thoroughly  mixed  with  I  c.c.  phenol  sulphonic  acid  (made  by 
