Am.  Jour.  Pharni. \ 
January,  1395.  J 
Gaultherin. 
1 5 
briefly  reviewed  as  follows,  using,  as  far  as  possible,  the  exact  words  of 
the  writer:  (i)  as  establishing  the  identity  of  volatile  oil  of  Betula 
lenia  with  the  oil  of  gaultheria,  which  had  shortly  before  been 
proved  to  be  methyl  salicylate  by  M.  Cahours  ;  (2)  establishing  the 
existence  of  a  peculiar  principle  in  the  bark  of  Betula  lenia,  which 
bears  the  same  kind  of  relation  to  the  oil  of  gaultheria  or  Betula 
lenta  that  amygdalin  bears  to  the  oil  of  bitter  almond,  and  which 
was  called  gaultherin,  as  it  gave  rise  to  the  oil  of  gaultheria  by  its 
decomposition;  the  term  betulin  was  admitted  to  be  more  appropriate, 
but  had  already  been  applied  to  another  substance ;  (3)  the  exist- 
ence in  the  bark  of  Betula  lenta,  associated  with  gaultherin,  of  a 
substance  enjoying  the  property  of  reacting  with  the  latter  so  as  to 
produce  the  volatile  oil,  and  which  is  analogous  in  its  mode  of  opera- 
tion to  synaptase  or  emulsin.  The  constituents  of  the  bark  of 
Betula  lenta  were  given  as  tannin,  gum,  saccharine  matter,  resin  in 
considerable  quantity,  gaultherin,  fixed  oil  soluble  in  alcohol,  etc. 
The  dry  bark  does  not  possess  the  odor  peculiar  to  the  volatile  oil, 
but  the  latter  is  only  developed  by  contact  with  water,  recalling  the 
analogous  behavior  of  wild  cherry  bark.  The  powdered  bark,  ex- 
hausted by  maceration  and  displacement  with  cold  95  per  cent,  alco- 
hol, no  longer  gives  the  odor  of  the  oil  when  moistened  with  water; 
the  alcoholic  solution,  evaporated  to  an  extract  and  mixed  with  a 
part  of  the  exhausted  bark  and  water,  immediately  developed  the 
odor,  and  by  distillation  yielded  a  liquid  which  gave  all  of  the  tests 
for  the  oil  of  Betula  lenta. 
The  leaves  of  Gaultheria  procumbens,  after  drying,  did  not  yield 
the  same  principle  ;  the  leaves,  when  long  kept,  lose  their  odor,  and 
mixture  with  water  does  not  revive  it  as  with  Betula  lenta  ;  hence, 
it  would  seem  that  the  methyl  salicylate  is  an  immediate  product  in 
the  Gaultheria  proenmbens,  whilst  in  the  Betula  lenta  it  is  secondary. 
To  purify  this  principle,  gaultherin,  the  alcoholic  extract  of  the  bark 
is  treated  with  water,  which  leaves  the  resin  and  fixed  oil ;  the  dark 
red  liquid  so  obtained,  containing  tannin,  extractive  and  saccharine 
matter,  is  then  treated  with  an  excess  of  lead  hydrate  until  these 
substances  are  separated  and  the  transparent,  nearly  colorless  liquid 
obtained  by  filtration  is  carefully  evaporated.  A  transparent,  gummy 
mass  results,  which  almost  wholly  dissolves  in  97  per  cent,  alcohol ; 
the  alcoholic  solution  by  spontaneous  evaporation  yields  a  syrupy, 
almost  colorless  product,  which  does  not  crystallize  after  standing 
