Of   all   the  essential   oils,  that  of   lemon  is   the   sheet-anchor  of   the

confectioner,  and  used  in  just  the  right  proportion  none  is  more  pleasant

and  refreshinof.    Unfortunately  this  essence  is  sometimes  used  ^.,     .  _

.  ,.,...  ,.  „     ,       Oil  of  Lemon,

in  such  lavish  quantity  to  mask  interior  ingredients  of  the

mixing  that  there  is  danger  of  its  falling  into  bad  repute.  Oil  of  lemon
is  obtained  from  the  fruit  of  Citrus  limonuTn.  It  is  generally  prepared
during  the  months  of  November  to  April.  The  chief  centre  of  the  in-
dustry is  Messina,  though  much  is  also  produced  in  the  Palermo  district
of  Sicily.  The  oil  is  obtained  sometimes  by  means  of  strong  pressure
upon  the  rinds,  by  which  the  oil  cells  become  ruptured  and  the  oil  escapes
and  is  collected  on  the  surface  of  water.  Another  method  consists  in
removing  the  rinds  in  three  pieces,  scraping  the  surfaces,  and  pressing
upon  a  sponge.  The  sponge  is  afterwards  squeezed  to  recover  the  oil.
By  this  process  a  worker  can  produce  1^  lb.  of  lemon  oil  per  day.  Re-
covery by  distillation  is  not  practised  except  in  the  case  of  poor  qualities,
since  lemon  oil  is  injured  by  this  process.  To  purify  the  oil  it  is  simply
filtered.
Citral  is  the  constituent  to  which  the  flavour  and  odour  of  lemon  oil  are
chiefly  due,  and  it  occurs  in  pure  oil  to  the  extent  of  about  5  to  7  per  cent.
The  great  bulk  of  the  remainder  of  even  pure  lemon  oils  Flavouring
consists  of  terpenes.  Unfortunately  even  the  citral  content  Agent  m  Lemon,
cannot  be  relied  upon  as  a  test  of  purity,  for  low-grade  lemon  oils  are
commonly  fortified  by  the  addition  of  citral  obtained  from  lemon-grass  oil.
