ON  ESSENTIAL  OIL  OF  GINGER. 
129 
ON  ESSENTIAL  OIL  OF  GINGEli. 
By  A.  Papousek. 
The  root  of  Zingiber  officinale  contains,  according  to  Morin, 
an  essential  oil.  To  obtain  this  in  sufficient  quantity,  ginger  was 
submitted  to  distillation  with  water.  With  the  water  a  yellow 
oil  goes  over,  which  possesses  in  a  high  degree  the  odor  of  ginger, 
and  a  burning  aromatic  taste.  Its  boiling  point  is  475°  F.,  its 
specific  gravity  0-893. 
The  raw  oil  was  deprived  of  water  by  pieces  of  fused  chloride 
of  calcium,  and  kept  in  a  retort  at  a  temperature  below  its  boil- 
ing point.  At  302°  F.  a  colorless  oil  evaporated,  which  on 
analysis  gave  the  following  numbers : 
Carbon  ....    81-03       80  =  81-49 
Hydrogen      .       .       .11-58       69  11-72 
Oxygen         .       .       .     7-39         5  6-79 
Qso  h69  O5  —  C80  H64  +  5HO.    This  oil  is  therefore  a  mixture  of 
hydrates  of  a  hydrocarbon  isomerous  with  oil  of  turpentine. 
As  the  oil  acquired  a  darker  color  and  began  to  undergo  de- 
composition (as  was  known  by  the  formation  of  water)  when  the 
heat  was  continued,  the  distillation  was  carried  no  further. 
The  raw  oil  was  repeatedly  distilled  with  anhydrous  phos- 
phoric acid.  The  yellow  distillate  gave  the  following  numbers 
on  analysis  : 
Carbon  .  .  .  .87-99  10  =  88.24 
Hydrogen      .       .       .    11.88         8  11.76 
The  formula  C10  H8  places  this  oil  with  the  numerous  series  of 
hydrocarbons  usually  characterised  as  the  camphene  series.  The 
separation  of  the  hydrate-water  appears  to  be  effected  with 
equal  ease  by  the  action  of  muriatic  acid,  as  by  that  of  anhy- 
drous phosphoric  acid. 
If  muriatic  acid  gas  be  passed  into  the  raw  oil,  the  latter 
acquires  a  brown  color,  even  if  care  has  been  taken  by  cooling 
that  the  action  should  not  be  too  violent.  The  brown  oil,  satu- 
rated with  muriatic  acid,  was  washed  with  water,  then  submitted 
to  distillation  with  water,  and  the  product,  which  is  of  a  yel- 
lowish color  and  contains  chlorine,  dried  over  chloride  of 
calcium.  As  shown  by  analysis,  these  operations,  employed  for 
the  purpose  of  purification,  partially  decompose  the  muriatic 
acid  compound,  forming  a  mixture  of  a  muriatic  acid  compound 
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