400  Oils  of  Wintergreen  and  Birch.  {AmiJSPmm' 
and  the  residues  set  aside  to  evaporate  spontaneously.  When  the  solu- 
tions had  been  reduced  to  a  small  bulk,  they  were  transferred  to  small 
tared  bottles,  and,  with  stoppers  removed,  were  heated  for  some  hours 
in  a  water-bath  to  constant  weight. 
™,      .  t f  from  oil  of  wintergreen,  0*3     per  cent. 
The  yield  was  <     „       „   v .   ,  ~     -  , 
J  \    "       "    birch,  0-447  " 
Another  portion  of  each  oil  was  saponified  by  the  hot  process,  in 
which  the  flasks  containing  the  mixtures  were  attached  to  upright 
condensers  and  heated  for  several  hours  on  sand-baths.  The  saponi- 
fied oils  were  then  distilled  as  long  as  oily  drops  separated  from  the 
distillates,  and  each  of  these  distillates  agitated  with  ether.  The 
ethereal  solutions  were  treated  as  the  above  petroleum  ether  extractions 
and  the  yield  found  to  bej  from  oil  of  w^tergreen,  0-22   per  cent. 
J  I    "       "    birch,  0-084  " 
These  residues,  with  those  from  the  petroleum  ether,  correspond  to 
the  hydrocarbon  noticed  by  Cahours  in  oil  of  wintergreen,  and  named 
by  him  gaultherilene. 
The  products  from  the  two  oils  were  similar  in  odor.  They  both 
solidified  on  standing  for  a  day  or  two,  or  at  once  on  cooling.  That 
from  wintergreen  commenced  to  melt  at  10°C.  and  was  clear  at  15°C, 
but  the  hydrocarbon  from  birch  did  not  commence  to  melt  below 
18°C  and  was  clear  at  a  few  degrees  above  that  temperature.  The 
variation  in  yield  may  now  be  accounted  for  by  supposing  that  the 
hydrocarbon  in  oil  of  birch  exists  in  greater  quantity,  as  shown  by 
our  method  of  extracting  it,  but  in  the  hot  process,  in  which  distilla- 
tion was  used  in  the  separation  of  the  hydrocarbon,  a  part  of  that 
from  the  birch,  probably  not  being  so  volatile,  was  left  behind  in  the 
distillation. 
Even  with  the  comparatively  large  amounts  of  oils  used  the  quan- 
tities of  the  hydrocarbons  were  necessarily  limited,  therefore  they 
were  reserved  for  a  determination  of  their  chemical  composition, 
rather  than  risk  the  liability  of  loss  in  determining  the  specific  gravity 
and  boiling  point. 
It  may  be  said,  however,  that  both  were  lighter  than  water,  and 
had  boiling  points  near  200 °C.  No  residues  remained  on  the 
further  ap  plication  of  heat.  Portions  of  each  were  dissolved  in  al- 
cohol and  the  absence  of  traces  of  salicylic  acid  determined  by  ferric 
chloride. 
Composition. — The  hydrocarbon  obtained  by  our  method  from  oil 
