Am..rour  I'l.aim  I     prdcticdl  Noti'S  f rom  Forelr/n  Journal.-^.  15 
Jan.,  Ih^-J.  j 
over  with  paper  were  but  sliglity  oxidizeil,  the  ditfereiice  between  the 
total  amount  of  iron  and  that  in  the  ferrous  state  being  '09,  -11  and 
1*8  per  cent.  In  vessels  tied  over  witli  waxed  paper  or  bladder  the 
oxidation  was  greater;  in  cork-sto]:>pered  bottles  over  one-third  of  the 
iron  had  been  oxidized,  and  in  glass-stoppered  bottles  the  salt  liad 
spoiled  ver}^  rapidly.  The  cause  of  the  more  rapid  oxidation  of  fer- 
rous salts  in  tightly  closed  vessels  seems  to  dei)end  upon  the  produc- 
tion of  ozone,  which  from  loosely  closed  vessels  is  readily  diffused 
into  the  atmosphere.  If  a  bottle  partly  filled  with  ferrous  sulphate  is 
closed  with  a  cork  to  which  a  strip  of  paper  impregnated  with  starcli 
and  potassium  iodide  is  attached,  a  blue  coloration  of  the  paper  will 
soon  be  observed. — Reprint  from  Phar.  Zeitschr.  f.  Eussl. 
Reaction  of  Oil  of  Dipterocaiyus  and  Recognition  of  Mineral  Acids 
in  Vinegar. — Armand  Jorissen  observed  a  characteristic  color  reaction 
of  gurjun  oil  by  operating  as  follows:  Place  one  drop  of  gurjun  oil 
and  25  drops  of  glacial  acetic  acid  in  a  perfectly  dry  test  tube,  and  add 
one  drop  of  a  very  dilute  mineral  acid,  consisting,  for  instance,  of  5 
pafts  Il2S0jt  and  100  parts  of  water;  also  4  to  6  drops  of  the  acetic 
acid  for  the  purpose  of  rendering  the  mixture  clear.  The  liquid  at 
once  acquires  a  rose  color,  which  gradually  deepens  and  becomes  of  a 
violet  tint,  not  disappearing  on  the  addition  of  30  drops  of  alcohol, 
and  resembling  in  color  a  dilute  solution  of  potassium  permanganate. 
Oil  of  copaiba  produces  under  the  same  conditions  a  faint  rose 
color,  which  disappears  on  the  addition  of  the  alcohol. 
The  above  reaction  may  be  used  for  detecting  mineral  acids  in  vin- 
egar. To  a  mixture  of  one  drop  of  gurjun  oil  and  2d  drops  of  glacial 
acetic  acid  one  drop  of  the  vinegar  is  added,  and  after  agitation  4  to  (> 
drops  of  acetic  acid.  A  mixture  of  9  parts  of  pure  vinegar  and  one 
part  of  normal  sulphuric  acid  (containing,  therefore,  nearly  yoto 
H2S()^)  produced  the  violet  color  in  7  minutes,  and  this  did  not  dis- 
appear on  the  addition  of  f30  drops  of  alcohol. 
No  color  was  produced  when  operating  with  vinegar  saturated  with 
cream  of  tartar  or  calcium  sulphate,  or  with  pure  vinegar  containing 
one  per  cent,  of  sodium  chloride,  tartaric  acid  or  oxalic  acid. — Jour,  dc 
Phar.  d'Anvers,  18S1,  ])p.  233  to  235. 
T/iyniate  of  sodium  was  prei)ared  by  Tanret,  but  found  to  be  dec;om- 
posed  on  dissolving  it  in  water,  while  it  dissolves  in  an  excess  {I  e(\u\- 
valent)  of  soda  without  deconi])osition.  J^yasson  regards  the  com- 
pounds of  thymol  or  thymic  acid  with  alkalies  as  not  being  true  salts. 
