DETECTION  OF  CARBOLIC  ACID  IN  OIL  OF  CLOVES.  521 
of  ammonium.  In  the  presence  of  turpentine,  however,  this 
last  residue  contains  about  three- fourths  of  the  resin  of  the 
adulteration,  and  yields  with  potassa  a  liquid,  in  which  sulphide 
of  ammonium  produces  a  bulky  brown-black  precipitate.  The 
lead  compound  of  the  resin  of  turpentine  is  soluble  in  benzin 
and  alcohol,  but  not  the  corresponding  compound  with  the  resin 
of  copaiva.— PA.  Cent.  Halle,  1870,  296,  297.  M. 
ON  THE  OXIDATION  OF  BRUCIA. 
By  Schcenn,  of  Stettin. 
Brucia  is  still  sometimes  employed  as  a  test  for  nitric  and  ni- 
trous acids.  The  red  color  passing  into  yellow,  produced  by  a 
solution  of  brucia  in  concentrated  sulphuric  acid  with  nitric  or 
nitrous  acid,  is  not  the  result  of  the  formation  of  a  nitro  com- 
pound, but  the  result  of  oxitlation,  and  may  likewise  be  obtained 
by  chlorine  water,  peroxide  of  hydrogen,  very  dilute  chlorate 
of  potassa,  very  dilute  chromic  acid  or  chromate  of  potassa,  di- 
lute hypochlorite  of  soda,  ferricyanide  of  potassium,  bichloride 
of  platinum,  &c.  If  a  drop  of  cupric  chloride  is  added  upon  a 
few  drops  of  solution  of  brucia,  a  rose-color  is  produced  near 
the  yellow  margin  resulting  from  the  influence  of  the  sulphuric 
acid. 
The  reaction  is  observed  with  auric  and  ferric  chlorides  only 
by  not  exceeding  certain  definite  proportions.  That  the  color 
is  in  reality  a  product  of  oxidation  is  more  evident  by  the  de- 
coloration produced  by  protochloride  of  tin  with  some  muriatic 
acid.— PA.  Cent.  Halle,  1870,  283,  284,  from  Fresenius  Zeitschr. 
f.  anal.  Chem.  M. 
DETECTION  OF  CARBOLIC  ACID  IN  OIL  OF  CLOYES. 
Hager  (PA.  Centr.  Halle,  1870,  281)  agitates  the  suspected 
oil  with  six  to  ten  times  its  volume  of  benzin  ;  pure  oil  of  cloves 
yields  a  clear  solution  ;  carbolic  acid,  if  present,  renders  the  mix- 
ture turbid  and  separates.  Equal  volumes,  however,  of  carbolic 
acid,  oil  of  cloves  and  benzin,  yields  a  clear  mixture. 
Carbolic  acid  may  likewise  be  removed  from  oil  of  clo-ves  by 
