^']°Z'^Ibo"°'}  Gleanings  from  the  German  Journals.  ii 
Mix  and  digest  for  a  few  hours,  stirring  from  time  to  time,  set  aside 
to  settle,  decant  the  liquid,  strain,  remove  a  portion  of  the  alcohol  by 
distilling  from  a  water-bath  and  dilute  the  remaining  mass  after  cooling 
with  sufficient  absolute  alcohol  to  give  the  mixture  a  thin  syrupy  con- 
sistence.— Pharm.  Centralh,^  Oct.  30,  1879,  p.  408. 
Action  of  Potassium  Permanganate  on  Oil  of  Turpentine. — 
Oil  of  turpentine,  when  kept  for  some  time  in  partly-filled  and  not  air- 
tight bottles,  resinifies  (oxidizes)  to  a  certain  extent,  and  then  possesses 
bleaching  properties,  which  were  formerly  attributed  to  the  presence  of 
ozone  in  the  old  oil.  Boettger's  recent  investigations  prove,  however,  that 
it  contains  no  ozone,  but  traces  of  hydrogen  peroxide.  This  can  be 
shown  by  oxidizing  a  fresh  distilled  oil  by  adding  to  it,  drop  by  drop^ 
stirring  continually,  an  aqueous  potassium  permanganate  solution,  when 
the  oil  becomes  gradually  loaded  with  hydrogen  peroxide. — Pharm.  Post^ 
Nov.  I,  1879,  p.  325,  from  Polyt.  Notizbl. 
The  presence  of  hydrogen  peroxide  in  partially  oxidized  oil  of 
turpentine,  is  detected  by  pouring  a  little  ethylic  ether  on  a  few  cubic 
centimeters  of  the  oil  contained  in  a  test-tube,  and  adding  double  its 
bulk  of  distilled  water,  a  few  drops  of  starch  solution  containing 
cadmium  iodide,  and  a  small  crystal  of  iron  sulphate.  On  gently  agitat- 
ing the  test-tube  the  lower  aqueous  layer  will  turn  intensely  blue  in  a 
few  minutes  in  case  hydrogen  peroxide  is  present. — Pharm.  Ztg..^  Nov^ 
I,  1879,  p.  326,  from  Polyt.  Notizbl. 
Tests  for  Adulterations  in  Volatile  Oil  of  Mustard.  —  Hager 
recommends  the  following: 
1.  Evaporation. — One  or  two  grams  of  the  oil  are  evaporated  in  a 
shallow  dish  at  from  40°  to  50°C.  If  pure,  the  oil  evaporates  totally 
in  the  course  of  two  hours ;  a  residue  indicates  the  presence  of  fatty 
oils,  phenol,  oil  of  cloves,  oil  of  cinnamon  or  myrbane  oil,  etc. 
2.  Dropping  into  cold  water. — Strictly  pure  oil  sinks  in  water,  and 
remains  clear  for  hours.  If  the  drops  become  cloudy  or  milky  in  a 
minute,  i  per  cent,  of  alcohol  or  amylic  alcohol  is  present. 
3.  Pure  concentrated  sulphuric  acid. — Ten  drops  of  the  oil  are  mixed 
in  a  test-tube  with  4  or  5  cc.  of  sulphuric  acid,  when  no  change  of 
color  is  produced  if  the  oil  is  purej  a  darker  coloration  indicates  the 
presence  of  adulterations,  such  as  fatty  oils,  myrbane  oil,  carbon  bisul- 
phide, chloroform,  etc. 
