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ARABIAN  MANNA. 
which  I  have  arrived,"  says  M.  Lallemand,  "differ  with  those 
already  mentioned  in  works  on  chemistry,  and  render  very 
probable  the  fact  that  the  product  analysed  by  M.  Pelouze 
under  the  name  of  essence  of  Borneo  had  not  been  extracted 
from  the  JDryobalanops  Camphora  (the  largest  tree  of  the  Indian 
Archipelago)."  The  researches  contained  in  the  author's  paper 
show  that  the  oil  of  Dryobalanops  is  a  complex  mixture  analo- 
gous to  the  turpentine  obtained  from  pines  and  firs.  Its  origin 
would  make  us  suppose  that  it  contained  Borneo  camphor :  M. 
Lallemand  assures  us,  however,  that  it  does  not  contain  a  trace. 
The  oil  which  exudes  from  the  tree  by  incision  does  not  differ 
from  that  obtained  by  decoction  ;  they  have  both  the  same 
rotatory  power  and  the  same  viscosity.  The  quantity  experi- 
mented upon  was  too  small  to  permit  of  further  research.  The 
camphor  oil  extracted  from  Laurus  Camphora  has  already  been 
analysed  by  Martius  and  Richer,  who  looked  upon  it  as  a  first 
degree  of  oxidation  of  camphor,  and  represented  it  by  the 
formula  C20H16O.  Gerhardt  supposed  it  to  be  a  mixture  of 
camphor  and  a  hydrocarbon,  and  M.  Lallemand  confirms  this 
view. 
"  I  have  also  determined,"  says  the  latter  author,  "the  com- 
position of  some  of  the  most  abundant  essences  of  the  Lahiatm 
family,  which  I  possessed  in  a  pure  state.  The  essential  oil  of 
rosemary,  of  common  lavender  [Lavandula  spica)  and  cultivated 
lavender,  consist  of  mixtures  analogous  to  oil  of  camphor,  and 
show  us  to  what  extent  the  molecule  C20H16  and  its  immediate 
derivatives  are  distributed  throughout  the  vegetable  world. — 
Chem  Neivs,  Jan.  14,  1860  from  Hep.  de  JPharm.,  Oct.,  1859. 
ARABIAN  MANNA. 
Dr.  Landerer,  pharmaceutist  to  the  King  of  Greece,  and 
Prof,  of  Chemistry  in  the  University  of  Athens,  publishes  the 
following  notice  of  this  article.  The  Arabians  call  the  root  of 
Cyperus  Esculentus  Manna.  It  is  one  of  the  most  useful  plants 
to  them  as  food,  side-dish  and  dessert,  thanks  to  its  pleasant 
almond  taste.  In  case  of  sickness,  they  make  a  pleasant-tast- 
ing sherbet  of  this  root,  preferable  to  the  best  milk  of  almonds, 
and  the  syrup,  prepared  from  an  emulsion  of  the  Cyperus,  will 
