6oo  Determination  of  Camphor.  \AmsIptr'miTm' 
DETERMINATION  OF  CAMPHOR  IN  CAMPHORATED 
OILS. 
By  D.  A.  Wallace  and  S.  B.  Plummer. 
The  object  of  this  investigation  was  to  determine  the  experi- 
mental conditions  for  the  correct  estimation  of  camphor,  dissolved 
in  cottonseed,  olive,  peanut  and  sesame  oil,  by  the  methods  of,  firstly, 
volatalizing  the  camphor ;  secondly,  by  the  use  of  a  saccharimeter  with 
a  bichromate  cell.  These  oils  were  selected  as  being  those  specified 
by  the  British  or  United  States  Pharmacopoeia. 
The  first  method  consists  in  heating  a  known  weight  of  cam- 
phorated oil  at  i2o°  C.  until  the  camphor  has  volatalized,1  the  loss  in 
weight,  after  allowing  for  the  change  in  weight  of  the  oil,  represent- 
ing the  amount  of  camphor  contained  in  the  sample.  The  time  neces- 
sary for  complete  evaporation  at  this  temperature  was  determined. 
Likewise  an  examination  of  the  oils  before  and  after  heating,  with 
and  without  camphor  was  made,  to  find  what  changes  in  such  phys- 
ical and  chemical  properties  of  the  oils,  as  refractive  index,  iodinf 
absorption  and  saponification  values  had  taken  place.  Likewise  the 
change  in  weight  on  heating  the  oils  alone  was  measured. 
Japanese  camphor  was  resublimed  many  times  in  ordinary  desic- 
cators placed  on  a  warm  electric  plate,  until  further  sublimation  failed 
to  change  its  melting  point,  the  camphor  so  obtained  was  used 
throughout  as  being  sufficiently  pure  for  the  purpose. 
In  Table  I  are  given  the  physical  and  chemical  constants  of  the 
oils  employed;  the  specific  gravities  were  determined  by  the  West- 
phal  balance  at  150  C,  the  refractive  indicies  were  determined  by 
both  the  Zeiss-Butyro  and  Abbe  refractometers  at  400  C,  the  saponi- 
fication values  were  made  according  to  Kottestorfer's  process  and 
the  iodine  numbers  by  Wijs'  method.  The  values  recorded  are  the 
average  of  two  or  more  determinations. 
table  I. 
Butyro-Refract-  Abbe  Saponification  Iodine 
Oil                          S.  G.       0 meter.       Refr.  Value.  Number 
Cottonseed  ....    0.924       57.7       1.4648  198.7  110.4 
Peanut                   0.918       56.3       1.4639  192.8  97.8 
Olive                     0.916       54.0       1.4622  192.7  84.0 
Sesame                   0.923       58.5       1.4652  193. 1  104.6 
Allen's  Comm.  Organic  Chemistry,  Vol.  4,  p.  199. 
