260     Chemical  Examination  of  Ipomcea  Purpurea. 
Am.  Jour.  Pharm. 
June,  1908. 
water,  the  liquid  acidified  with  sulphuric  acid,  and  distilled  with 
steam.  The  first  portion  of  the  distillate  contained  a  brown-colored 
oil  of  disagreeable  odor  floating  on  the  surface.  The  entire  distillate 
was  therefore  first  extracted  with  ether  in  order  to  remove  the  oily- 
acid,  the  ethereal  liquid  being  washed,  dried,  and  the  solvent  re- 
moved. The  product  thus  obtained  was  distilled  under  a  pressure 
of  50  mm.,  when  it  passed  over  as  a  dark  yellow  oil,  showing  no 
constant  boiling-point,  and  amounted  to  1-5  grammes.  A  portion 
of  the  acid  was  converted  into  the  ammonium  salt,  and  from  this, 
by  fractional  precipitation  with  a  solution  of  silver  nitrate,  two 
silver  salts  were  prepared,  which  were  analyzed  with  the  following 
results : 
(I)  0-1574  of  salt  gave  on  ignition  00616  Ag.    Ag  =  39-1 
(II)  0-0982  "    "      «     "       "       0-0410  Ag.    Ag  =  417 
C9H1702  Ag  requires  Ag  =  40-8  per  cent. 
C10H19O2  Ag      «      Ag  =  387   "  " 
It  is  evident  from  these  results  that  the  oily  acids  represent  a 
mixture  of  somewhat  indefinite  composition. 
The  aqueous  distillate,  after  extraction  with  ether,  still  contained 
some  acid,  which  was  converted  into  a  barium  salt,  of  which  about 
7  grammes  were  obtained.  This  salt  afforded  reactions  indicating 
the  presence  of  formic  and  butyric  acids.  After  drying  at  I  io°  C. 
it  was  analyzed  : 
o  2866  of  the  dried  salt  gave  o  2580  BaSi4.    Ba  =  52-9. 
(CH02)2   Ba  requires  Ba  =  60  4  per  cent. 
(C4H702)2  Ba      "       Ba  =  44-1    «  « 
This  salt  would  thus  appear  to  have  consisted  of  barium  formate 
and  butyrate  in  about  equal  proportions. 
After  the  removal  of  the  volatile  acids  by  steam,  as  above  de- 
scribed, there  remained  in  the  distillation  flask  a  quantity  of  resin 
and  an  aqueous  liquid,  which  were  separated  by  filtration.  The 
aqueous  liquid  was  extracted  with  ether,  and  from  this  ethereal 
liquid,  after  the  removal  of  the  solvent,  a  small  amount  of  a  dark 
red  syrup  was  obtained.  The  latter,  when  dissolved  in  .  water, 
yielded  with  ferric  chloride  the  characteristic  catechol  reaction,  and, 
after  treatment  with  animal  charcoal,  deposited  a  very  small  amount 
of  a  substance  in  the  form  of  small,  crystalline  plates.  This  sub- 
stance melted  sharply  at  103-1040  C,  was  acid  to  litmus,  and  gave 
