Am*Apriiri9ih3arm' }      Constituents  of  Taraxacum  Root.  169 
ether,  the  ethereal  liquid  dried,  and  the  solvent  removed,  when  a 
small  amount  of  a  dark  yellow  essential  oil  was  obtained.  This 
oil  had  a  strong,  persistent  odor,  and  gave  the  color  reaction  for 
furfuraldehyde. 
Non-volatile  Constituents  of  the  Extract. 
After  the  above-described  operation  there  remained  in  the  distil- 
lation flask  a  dark-colored  aqueous  liquid  (A),  together  with  a 
quantity  of  a  soft,  somewhat  oily  resin  (B).  The  resinous  material, 
the  separation  of  which  was  attended  with  considerable  difficulty, 
was  finally  washed  thoroughly  with  warm  water,  and  the  washings 
added  to  the  main  portion  of  the  aqueous  liquid. 
Examination  of  the  Aqueous  Liquid  (A). 
The  aqueous  liquid,  after  concentration  under  diminished  pres- 
sure, was  extracted  many  times  with  ether.  These  ethereal  liquids 
were  united,  the  greater  portion  of  the  solvent  removed,  and  the 
residue  mixed  with  about  an  equal  volume  of  light  petroleum 
(b.  p.  35 — 500),  when  a  red  oil  was  deposited.  On  decanting 
and  concentrating  the  supernatant  liquid,  and  again  treating  it 
with  light  petroleum,  further  small  quantities  of  red  oil  were 
obtained,  which  were  added  to  the  first  portion.  The  mixture  of 
ether  and  light  petroleum  was  finally  evaporated,  the  residue  dis- 
solved in  ether,  and  the  ethereal  liquid  shaken  successively  with 
aqueous  ammonium  carbonate,  sodium  carbonate,  and  sodium 
hydroxide.  Each  of  these  alkaline  liquids  was  acidified,  extracted 
with  ether,  and  the  solvent  evaporated. 
Isolation  of  p-Hydroxyphenylacetic  Acid, 
C6H4(OH).CH2.C02H. 
The  product  obtained  from  the  above-mentioned  ammonium 
carbonate  extract  was  a  dark  yellow  oil.  This  was  treated  with  hot 
water  and  a  little  animal  charcoal,  and  the  liquid  filtered,  when,  on 
cooling,  a  gum-like  mass  separated,  which  gradually  became  crystal- 
line. After  recrystallisation  from  benzene  containing  a  little  ethyl 
acetate,  a  very  small  amount  (about  0.05  gram)  of  an  acidic  sub- 
stance was  obtained,  which  separated  in  colorless  needles,  melting 
at  144 — 145  °.  The  above-mentioned  red  oil,  which  was  deposited 
by  the  addition  of  light  petroleum  to  the  concentrated  ethereal 
liquid,  was  redissolved  in  ether,  and  extracted  successively  with 
