134 
ATTAR  OP  ROSE. 
any  such  body  which  is  not  at  once  recognizable  even  by  a  per- 
son of  small  experience  does  not  (to  the  author's  knowledge) 
exist. 
Almost  the  only  substance  at  present  known  with  which  rose- 
oil-stearoptene  can  be  replaced,  or  in  other  words  which  can  be 
employed  to  conceal  the  addition  of  another  essential  oil  and 
consequent  reduced  proportion  of  stearoptene,  is  spermaceti. 
This,  however,  effects  the  purpose  in  but  a  clumsy  manner,  for  it 
soon  separates,  settling  down  as  a  solid  cake,  and  forming  none 
of  the  long,  light,  peculiar  crystals  which  characterize  the  true 
stearoptene.  It  also  exhibits,  upon  shaking,  a  peculiar  iridescent, 
muddy  looking  appearance  [irisirende  $clilierenhildung~\.  The 
crystals  [when  separated]  melt  at  122°  Fahr.  and  leave  on 
paper  a  strong  stain  of  grease.  If  a  sample  of  attar,  suspected 
to  be  adulterated  with  spermaceti,  is  placed  when  near  the  temp- 
erature of  congelation  in  a  centrifugal  machine,  the  spermaceti 
if  present,  will  in  a  few  minutes  be  driven  to  the  bottom  of  the 
bottle  in  which  the  sample  is  contained :  this  adulteration  is  thus 
easily  recognized.  Pure  rose-oil-stearoptene  fuses  at  33°  C. 
(91-4°  Fahr.),  volatilizes  completely  from  paper  on  careful 
warming,  is  specifically  lighter  than  the  elseoptene  and  much 
lighter  than  spermaceti.    It  is  inactive  to  polarized  light. 
Other  adulterations,  as  for  instance  with  margaric  acid,  are 
difficult.  Although  the  substitution  of  other  substances  for  the 
true  stearoptene  is  easily  detected,  the  author  has  had  occasion  in 
many  instances  to  suspect  adulteration,  and  often  when  the  cor- 
pus delicti  has  been  regarded  by  connoisseures  and  chemists  as 
unquestionably  spermaceti,  he  has  proved  it,  on  closer  examina- 
tion, to  be  merely  the  stearoptene  of  the  attar. 
If  the  admixture  of  spermaceti  is  proved,  there  is  still  the 
question  of  adulteration  with  essential  oil,  and  this  is  in  fact 
much  more  frequent,  and  alas !  of  much  more  difficult  recogni- 
tion. 
The  admixture  in  question  relates  entirely  to  the  so-called 
Geranium-  or  Palmarosa-Oil.  That  oil  of  rhodium  and  oil  of 
sandalwood  are  mixed  with  attar,  as  stated  in  many  handbooks 
of  Materia  Medica,  or  that  such  a  mixture  can  be  substituted 
for  pure  rose-oil  is  for  any  person  who  has  once  in  his  life  smelt 
