272     Chemical  Examination  of  Ipomcea  Purpurea.     { Am  jt°e^908arm 
small  quantity  (0-5  gramme)  of  a  neutral,  oily  liquid  was  thus  ob- 
tained, which  was  more  viscid  than  the  corresponding  products 
from  the  previously-described  extracts  of  the  resin.  The  sodium 
carbonate  liquid  was  acidified  and  extracted  with  ether,  when  a  very 
small  amount  of  an  oily  acid  was  obtained,  from  which  a  silver  salt 
was  prepared  and  analyzed  : 
0-1208  of  salt  gave  on  ignition  0-0600  Ag.    Ag  =  497 
C5H902  Ag  requires  Ag  =  517  per  cent. 
C«Hu02Ag     «       Ag  =  48'4   "  " 
The  acids  remaining  in  the  aqueous  distillate  after  extraction  with 
ether  were  converted  into  a  barium  salt,  of  which  18  grammes  were 
obtained.  This  salt  afforded  reactions  which  established  the  pres- 
ence of  formic  and  butyric  acids.  After  drying  at  no°  C.  it  was 
analyzed  with  the  following  results  : 
0-5588  of  the  dried  salt  gave  0-3898  BaS04.  Ba  =  41-0 
0  8000  "    "     "      "     "     0-5584  BaS04.    Ba  =  41  o 
As  this  salt  contained  a  considerably  lower  percentage  of  barium 
than  that  required  for  barium  butyrate  (44-1  per  cent.  Ba),  it  must 
also  have  contained  some  acid  of  higher  molecular  weight. 
After  the  removal  of  the  above-described  volatile  products  by 
distillation  with  steam,  and  allowing  the  contents  of  the  distillation 
flask  to  cool,  it  was  observed  that  a  small  quantity  of  a  white  solid 
had  separated,  and  that  the  resinous  matter,  which  formed  a  solid 
cake  floating  on  the  surface  of  the  liquid,  was  very  much  smaller  in 
amount  than  in  the  case  of  the  corresponding  products  from  the 
previously-described  extracts.  The  white  solid  substance  was  sepa- 
rated, dried  on  a  porous  plate,  and  crystallized  from  hot  water,  from 
which  it  separated  in  fine,  long,  interlaced  needles,  melting  at 
100-102°  C.  This  substance  was  evidently  identical  with  a  new  acid, 
C14H2804,  which  was  subsequently  isolated  from  the  above-mentioned 
cake  of  resinous  matter,  and  will  presently  be  described. 
The  acid  filtrate  from  the  white  solid  substance  and  resinous 
matter  was  extracted  with  ether,  the  ethereal  liquid  being  shaken 
with  a  solution  of  sodium  carbonate,  then  washed  with  water,  dried, 
and  the  ether  removed.  Only  a  trace  of  a  neutral  oily  liquid  was 
thus  obtained,  which  gave  no  coloration  with  ferric  chloride.  The 
sodium  carbonate  liquid,  which  had  a  dark  red  color,  was  acidified 
and  extracted  with  ether,  the  ethereal  liquid  being  dried  and  the 
