300 
GLEANINGS  FROM  THE  FRENCH  JOURNALS. 
the  three  non-coagulable  oils  above  stated..-- -Journ.  de  Pharm. y 
Mai.,  1866. 
New  means  of  discovering  Iodine  in  Liquids. — M.  Laronde 
suggests  the  use  of  petroleum  oil  for  this  purpose;  ten  grammes 
of  the  liquid  to  be  assayed  is  put  in  a  test  tube  with  one  gramme 
of  the  oil  and  agitated ;  drop  in  a  few  drops  of  nitric  acid,  and 
then  two  drops  of  liquid  chloride  of  lime  and  again  agitate.  The 
oil  S3on  rises  to  the  surface  with  all  the  iodine  in  solution,  with 
a  more  or  less  rose  water. — Journ.  de  Pharmacie. 
Soluble  Citrate  of  Magnesia  Crystallized.  By  M.  Morelli,  of 
Lille. — I  have  recently  noticed  in  the  Repertoire  de  Pharmacie, 
a  process  for  obtaining  crystallized  citrate  of  magnesia.  It  is 
about  two  years  that  I  have  been  in  the  habit  of  preparing  it  for 
use  in  my  shop  by  a  different  method.  My  method,  because  of 
its  easy  execution,  it  appears  to  me,  will  be  of  use  to  my  con- 
freres, which  is  the  reason  I  make  it  known  through  your  excel- 
lent Journal. 
Take  of  Citric  acid,  in  powder,  1400  parts. 
Sub- carbonate  of  magnesia,  660  " 
Water,  550  " 
These  substances,  mixed  intimately  in  an  earthen  vessel,  form 
a  liquid  paste  which  swells  up  by  the  reaction  between  the  acid 
and  carbonate.  It  is  necessary  to  stir  the  mass  from  time  to 
time  with  a  wooden  spatula.  After  an  hour  or  two  the  disen- 
gagement of  carbonic  acid  ceases  and  the  materials  are  slowly 
transformed  into  a  crystalline  mass  analogous  to  moist  sugar.  It 
is  finished  by  drying  in  the  air.  This  salt  being  in  microscopic 
crystals  dissolves  very  rapidly  in  four  times  its  weight  of  water ; 
it  is  the  bi-metallic  citrate  of  M.  Perret.  The  proportion  of  sub- 
carbonate  is  two-thirds  of  that  necessary  to  saturate  the  acid.  It 
is  necessary  to  use  an  acid  and  carbonate  of  great  purity. 
Although  this  salt  has  a  very  acid  taste,  an  agreeable  solution 
can  be  obtained  by  the  following  recipe  : 
Take  of  Crystallized  citrate  of  magnesia,       694  grains. 
Bi-carbonate  of  soda,  77  " 
Syrup,  770  " 
Water  sufficient  for  half  a  bottle. 
— Repert.  de  Pharm.,  Mai,  1866. 
