A  !&5Sy.PiSJm  }  G  mil  t  her  in.  1 7 
and  precipitating  the  lead  with  hydrogen  sulphide,  a  solution  is  ob- 
tained containing  the  acid  in  a  much  purer  state,  which,  by  evapo- 
ration, yields  it  in  a  nearly  colorless  mass  with  some  evidence  of 
crystallization.  Gaultheric  acid  is  soluble  in  water  and  alcohol,  but 
is  only  slightly  taken  up  by  ether.  It  saturates  bases,  forming  neu- 
tral salts  which  do  not  crystallize.  By  distilling  it  with  dilute  sul- 
phuric acid,  oil  of  gaultheria  is  obtained,  and  nitric  acid  appears  to 
act  on  it  like  gaultherin. 
The  substance  existing  in  the  residue  of  the  bark,  after  exhaustion 
by  alcohol,  and  which  reacts  with  gaultherin  to  produce  the  volatile 
oil,  has  not  been  isolated.  Tt  is  insoluble  in  water,  as  by  long 
maceration  in  that  fluid  it  is  not  removed  or  changed.  The  tem- 
perature of  ebullition,  as  well  as  maceration  in  solution  of  potassa 
sp.  gr.  1 .05,  destroys  its  power  of  acting  upon  gaultherin.  The  impos- 
sibility of  finding  a  menstruum  capable  of  dissolving  this  principle, 
has  prevented  a  further  examination  of  its  properties. 
It  will  be  interesting  to  know  the  ultimate  composition  of  this 
principle  and  the  relation  it  bears  to  gaultheric  acid  and  methyl 
salicylate  ;  before  that  can  be  accomplished,  the  necessity  of  obtain- 
ing it  in  a  pure  state  is  imperative.  It  is  hoped  that  the  attention 
of  chemists  will  be  attracted  to  these  principles,  and  their  character 
more  fully  developed. 
Just  about  fifty  years  have  elapsed  since  the  publication  of  the 
above  experiments  without  any  further  investigation  being  recorded. 
In  Archiv  der  Pharmacie,  1894,  page  437,  there  is  to  be  found  the 
second  publication  bearing  upon  this  subject,  by  Dr.  A.  Schneegans 
and  J.  E.  Gerock.  These  writers  have  taken  as  their  field  of  labor 
the  separation  and  properties  of  glucosides  which,  by  their  decom- 
position, yield  volatile  oils.  Their  first  paper  bearing  upon  the 
volatile  oil  of  Spiraea  nlmaria  was  published  about  two  years  ago. 
The  results  of  this  investigation,  while  not  as  successful  as  antici- 
pated, disclosed  that  several  glucosides  were  present,  which,  by  their 
decomposition,  yielded  salicyl-aldehyde,  as  well  as  methyl  salicy- 
late, but  the  quantities  of  these  glucosides  which  are  present  was 
very  small,  so  that  their  preparation  in  a  state  of  purity  was  not 
successful. 
Turning  their  attention  next  to  the  glucoside  yielding  methyl 
salicylate  which  appeared  to  offer  more  promising  results,  the  bark 
