Am.  Jour.  Pharm.  \ 
January,  1898.  J 
Gum  from  the  Oil  Tree. 
15 
Professor  Trimble  kindly  supplied  the  author  with  the  remainder 
of  sample  of  gum  upon  which  he  worked,  for  the  purpose  of  making 
a  fractional  distillation,  with  a  view  of  determining  the  composition 
of  the  several  fractions  which  had  been  noticed  in  the  previous  dis- 
tillation. 
Before  beginning  a  fractional  distillation,  the  gum  was  filtered 
through  absorbent  cotton  in  a  hot  filtration  funnel.  The  filtration 
proceeded  slowly,  and  it  was  noticed  that  the  filtrate  was  much 
clearer  than  the  original  sample,  which  phenomenon  was  probably 
due  to  the  loss  of  the  small  quantity  of  adhering  water  through 
vaporization ;  at  the  same  time  the  suspended  greenish  substance 
was  removed  by  the  filtering  medium. 
This  greenish  substance  was  likely  sap  which  had  oozed  out  from 
the  tree  with  the  gum. 
The  clear  filtered  liquid  was  found  to  have  a  specific  gravity  of 
1008  at  1 50  G. 
Metallic  potassium  immersed  in  the  gum  remained  bright  for 
some  days,  then  gradually  oxidized  and  disappeared  in  the  gum 
without  altering  the  transparency,  color  or  consistency  of  the  liquid 
to  any  appreciable  extent.  The  product  of  this  solution  behaved 
with  water  in  the  same  way  as  Professor  Trimble  found  aqueous 
solutions  of  sodium  and  potassium  hydrates  to  act  on  the  original 
material. 
In  order  to  make  a  fractional  distillation  of  the  gum,  125  grammes 
of  the  original  material  were  placed  in  a  flask  attached  to  a  vacuum 
condenser  and  heat  applied.  The  vacuum  gauge  showed  a  pressure 
of  254  millimetres.  As  the  temperature  of  the  gum  was  increased, 
the  peculiar  cracking  sound,  recorded  by  the  previous  investigator, 
was  observed,  and  a  few  drops  of  condensed  steam  collected  in  the 
receiver  as  the  heat  was  gradually  increased. 
When  the  liquid  had  reached  the  temperature  of  2400  C,  it  began 
to  boil,  but  nothing  distilled  except  the  small  amount  of  water. 
During  this  distillation  of  the  water  the  apparatus  was  filled  with 
a  heavy  white  vapor,  which  passed  into  the  aspirating  tubes,  and 
condensed  therein  to  oily  drops  resembling  the  distillate  subsequently 
gotten  from  the  gum. 
A  thermometer  suspended  in  the  gum  showed  a  temperature  of 
3600  C.  At  this  point  a  small  quantity  of  distillate  had  passed  over 
into  the  condenser,  but  the  temperature  of  this  distillate  was  but 
