io 
Gum  from  the  Oil  Tree. 
( Am.  Jour.  Pharm. 
\    January,  1898. 
The  distillates  became  more  viscous  toward  the  latter  part  of  the 
distillation;  but  when  they  were  redistilled  several  times  they  lost 
this  property  to  a  considerable  degree,  as  well  as  the  fluorescence 
which  was  present  in  all  cases. 
The  cracking  noise  which  accompanied  the  heating  of  the  gum, 
and  mentioned  by  the  previous  investigator,  was  observed  by  the 
writer  both  in  distilling  it  under  reduced  and  the  ordinary  pressure. 
The  gum  did  not  begin  to  boil  until  the  temperature  of  3600  C. 
was  reached,  then  it  began  to  yield  a  distillate  having  a  temperature 
of  21 50  C,  but  only  15  c.c.  of  distillate  had  collected  by  the  time 
the  temperature  of  the  distilling  liquid  had  attained  the  temperature 
of  3600  C.  The  temperature  at  which  the  vapor  passed  over  under 
reduced  pressure  was  150  less  than  under  ordinary  pressure. 
The  following  specific  gravities  and  boiling  points  of  the  fractions 
were  found: 
Temperatures. 
Specific  Gravities.  Initial.  Final. 
Distillate    I   '949  1150  C.        above  3600  C. 
II  -   -964  1700  C.  "       "  - 
III.  ......     -975       above  3600  C 
IV   '947 
Three  successive  distillations  were  made  on  each  of  the  four  distil- 
lates; but  it  was  found  impossible  to  get  a  fraction  having  a  definite 
boiling  point,  so  they  were  not  further  distilled. 
At  this  juncture  it  was  decided  to  make  an  ultimate  analysis  of 
the  fraction  which  was  obtained  between  1 1 5  0  C.  and  265 0  C.  under 
reduced  pressure  of  200  to  250  millimetres.  For  this  purpose  the 
upper  layer  of  the  fraction  was  removed  and  thoroughly  dried  with 
potassium  carbonate  to  remove  the  adhering  water,  then  decanted 
and  redistilled  under  ordinary  pressure.  The  distillate  so  obtained 
consisted  of  two  layers,  the  lower  of  which  was  water. 
This  continued  behavior  of  the  gum  in  giving  water  on  distilla- 
tion therefore  precluded  the  possibility  of  rectifying  the  oil  after 
drying  it  with  potassium  carbonate,  and  it  therefore  became  neces- 
sary to  remove  the  supernatant  layer,  allow  the  water  to  separate, 
as  nearly  as  possible,  and  then  take  the  clear  upper  layer  without 
rectification  lor  combustion. 
Several  combustions  were  made  upon  this  material  with  varying 
results  that  indicated  as  much  as  4  to  5  per  cent,  of  oxygen  in  the 
substance. 
