540  MYRONATE  OF    POTASSA  IN  BLACK  MUSTARD-SEED. 
even  on  inverting  the  vessel  ;  it  had  to  be  heated  to  70°  C. 
(153°  F.)  before  it  could  be  poured  out. 
The  residue  of  the  mustard  was  extracted  with  water  at  80°  C. 
(176Q  F.)  the  water  distilled  off,  but  no  crystals  of  myronate  of  pot- 
assa  were  obtained,  though  Bussy  alleges  the  presence  of  consider- 
able quantities  of  this  salt  in  the  above  infusion ;  with  white  mus- 
tard not  a  trace  of  essential  oil  was  produced. 
The  alcoholic  extract  is  insoluble  in  ether,  absolute  alcohol,  and 
a  mixture  of  both,  but  dissolves  in  warm  water ;  the  solution  was 
intensely  bitter,  and  easily  generated  the  ethereal  oil  with  white 
mustard,  but,  contrary  to  Bussy,  it  would  not  crystallize.  , 
On  the  addition  of  alcohol  to  the  concentrated  aqueous  solution, 
a  considerable  white  crystalline  precipitate  occurred,  which  proved 
to  be  pure  sulphate  of  potassa. 
The  solution  was  treated  with  yeast  to  destroy  the  sugar,  with 
acetate  of  lead  to  remove  sulphuric  and  gallic  acids  (the  latter  a 
product  of  decomposition  of  tannic  acid  during  the  manipulations), 
with  animal  charcoal,  albumen,  and  alumina,  to  remove  coloring 
matter,  but  the  latter  experiments  were  of  no  avail ;  all  these  treat- 
ments had  not  destroyed  the  fermentable  body,  but  it  would  not 
crystallize.  Chlorine  and  perchloride  of  tin  did  not  decolorize,  but 
destroyed  the  extract :  wolframate  (tungstate)  of  soda  and  muria- 
tic acid  did  both.  Tannic  acid  afterwards  precipitated  a  resinous 
and  a  glutinous  body,  but  the  syrup  retained  its  color  and  would  not 
crystallize. 
Caustic  alkalies  and  their  carbonates  in  large  quantities,  the  salts 
of  the  heavy  metallic  oxides,  hydrochloric,  sulphuric,  and  nitric 
acids,  as  well  as  phosphoro-molybdic,  tartaric,  oxalic,  acetic  and 
formic  acids  destroy  the  property  of  forming  oil  of  mustard,  which 
re-appears  on  the  neutralization  of  the  acids  with  potassa. 
The  ashes  contained  much  sulphate  of  potassa  and  phosphate  of 
lime,  sulphate  of  magnesia,  some  iron,  silicic  acid,  traces  of  muria- 
tic acid,  but  no  carbonic  acid. 
The  author  says,  Bussy  has  the  merit  of  having  discovered  the 
essential  oil  of  mustard  to  be  the  production  of  fermentation,  but 
declares  the  existence  of  myronic  acid  to  be  fabulous. — (Wittstein's 
Vierteljahresschrift,  vii.  161-170.)  J.  M.  M. 
