164  Gleanings  from  the  European  Journals.  {k%rT'^mlf% 
On  treating  the  concentrated  aqueous  solution  of  vanillic  acid  with 
bromine,  gradually  added,  a  precipitate  is  formed,  which  is  dissolved 
in  alcohol  agitated  with  mercury,  crystallized  and  purified  by  animal 
charcoal  and  boiling  water.  C16H7Br06  forms  pearly  crystals,  of  a 
yellowish  color,  fusing  at  16°  C. 
The  chlorinated  compounds  are  uncrystallizable. 
Oxyvanillic  acid,  C16H808,  is  obtained  in  white  odorless  prisms  by 
adding  vanillic  acid  to  fusing  potassa,  supersaturating  with  hydro- 
chloric acid,  and  crystallizing  first  from  ether,  afterwards  from  boiling 
water. 
The  author  concludes  that  vanillic  acid  is  isomeric  with  anisic,  for- 
mobenzoylic  (amygdalic),  methylsalicilic,  cresotic,  oxytoluic  and  a 
large  number  of  other  acids. — Journ.  de  Pharm.  et  de  Chim.,  1873, 
106-108. 
Antifermentative  properties  of  silicate  of  sodium. — According  to 
Mr.  Picot,  a  small  quantity  of  this  silicate  arrests  the  putrid  fermen- 
tation, retards  other  fermentations,  destroys  the  red  globules  outside 
of  the  organism  and  prevents  the  transformation  of  the  glycogen 
compound  of  the  liver  into  glucose. — Ibid.,  131. 
Malacca  Leocns,  the  fruit  of  Semccarjms  anacardium,  Lin.,  contain 
a  fixed  oil  of  a  black  color,  which  is  readily  exhausted  from  the  bruised 
fruit  by  digesting  it  in  fused  paraffin,  stearin,  &c,  so  that  black  can- 
dles may  be  obtained  without  having  their  illuminating  power  in  the 
least  impaired. — Prof.  Boettger,  in  Buchner's  N.  Repert.,  1873,  60. 
For  the  cleaning  and  i)olishing  of  silver  spoons  and  other  utensils. — 
Eisner  recommends  warm  water  in  which  potatoes  have  been  boiled, 
by  rubbing  them  between  the  fingers  with  the  fine  starchy  sediment  ; 
even  engraved  and  plated  articles,  as  well  as  such  of  German  silver, 
are  thus  easily  polished,  and  the  use  of  polishing  powders  rendered 
unnecessary.  Potato  water  which  has  turned  sour  on  standing  may 
be  used  for  polishing  copper,  instead  of  oil  of  vitriol. — Pharm.  Centr. 
Halle,  1873,  No.  5. 
Preparation  of  pure  oxalic  acid  and  oxalate  of  ammonium. — Habe- 
dank  dissolves  commercial  oxalic  acid  in  a  little  absolute  alcohol  and 
filters  from  the  insoluble  oxalates  of  calcium  and  potassium ;  the 
crystals  are  freed  from  some  oxalic  ether  by  recrystallization  from 
boiling  distilled  water.  » 
The  alcoholic  mother-liquor  may  be  used  for  dissolving  fresh  per- 
