148 
NEW  TEST  FOR  THE  PURITY  OF  CHLOROFORM. 
ingredients,  for  twenty  fluid  ounces  of  the  compound  tincture, 
according  to  the  Edinburg  formula  ;  having  properly  bruised 
them,  displace  with  diluted  alcohol  eighteen  fluid  ounces  of 
tincture.  Next  prepare  the  ammonio  citrate  of  iron  as  fol- 
lows : 
Take  of  Protosulphate  of  iron  crystallized,       379  grains. 
Carbonate  of  soda,       -  394  H 
Liquor  ammonia,        -  284  minims. 
Citric  acid,        -  189  grains. 
Refined  sugar,    -        -  2  ounces. 
Water ;  a  sufficient  quantity, 
Simple  Syrup ;  a  sufficient  quantity. 
Dissolve  the  protosulphate  of  iron  and  carbonate  of  soda, 
each  separately  in  four  fluid  ounces  of  water  and  mix  the  so- 
lutions adding  about  half  an  ounce  of  simple  syrup.  When 
the  precipitate  has  subsided  pour  off  the  supernatant  liquid  and 
wash  thoroughly  with  water  containing  about  a  fluid  ounce  of 
simple  syrup  in  each  pint ;  allow  it  to  settle  for  about  twelve 
hours  and  decant.  Transfer  the  precipitate  to  an  evaporating 
dish,  add  the  citric  acid,  and  when  the  solution  is  complete, 
the  liquor  ammonias,  then  the  sugar.  Evaporate  the  mixture 
to  two  fluid  ounces,  and  add  it  to  the  eighteen  fluid  ounces  of 
tincture. — Journal  and  Trans,  of  the  Maryland  Col.  of  Phar, 
NEW  TEST  FOR  THE  PURITY  OF  CHLOROFORM. 
{Translated  by  Prof.  L.  H.  Steiner,  from  the  French  of  M.  Roussin,  for  the 
Journal.') 
A  new  class  of  salts  called  double  nitro  sulphides  of  iron  has 
just  been  discovered,  and  nearly  all  the  representatives  of  the 
class  possess  the  very  singular  property  of  being  absolutely  in- 
soluble in  pure  chloroform,  although  soluble  in  water,  alcohol, 
ether  or  wood-spirit.  When  chloroform  contains  either  alcohol, 
ether  or  wood-spirit,  the  nitro-sulphide  is  dissolved  and  their 
presence  is  detected  by  a  deep  coloration  of  the  liquid.  In  fact 
all  the  nitro-sulphides  possess  great  coloring  properties ;  5  cen- 
tigrammes will  give  2  litres  of  alcohol  the  color  of  ordinary 
brandy.    Pure  chloroform  when  only  hydrated  will  not  be  dig- 
