^m jSnef  i908.arilJ " }     Chemical  Examination  of  Ipomcea  Purpurea.  263 
barium  salt  were  obtained.  This  afforded  reactions  indicating  the 
presence  of  formic  and  butyric  acids,  and,  after  drying  at  1  io°  C,  was 
analyzed  with  the  following  result : 
0-4848  of  the  dried  salt  gave  0-4420  BaS04.    Ba  ^=  537 
(CH02)2   Ba  requires  Ba  =  60-4  per  cent. 
(C4H.02)2Ba       "      Ba  =  44-1  per  cent. 
This  salt  would  thus  appear  to  have  consisted  of  barium  formate 
and  butyrate  in  approximately  equal  proportions. 
The  liquid  contained  in  the  distillation  flask  was  separated  from 
a  quantity  of  resin  and  extracted  with  ether,  which  removed  a  very 
small  quantity  of  substance  in  the  form  of  a  syrup.  This  gave  with 
ferric  chloride  the  catehol  reaction,  but  nothing  of  a  crystalline 
nature  could  be  obtained  from  it. 
Treatment  with  Dilute  Alcoholic  Sulphuric  Acid. — Twenty  grammes 
of  the  resin  were  dissolved  in  alcohol,  and  such  an  amount  of  sulph- 
uric acid  added  with  a  little  water,  that  the  total  liquid  contained 
about  5  per  cent,  of  its  weight  of  acid.  After  heating  for  about 
four  hours  in  a  reflux  apparatus,  the  alcohol  was  removed  and  the 
residue  distilled  with  steam.  The  distillate,  which  contained  some 
oily  drops,  was  extracted  with  ether,  the  ethereal  liquid  shaken  with 
a  solution  of  sodium  carbonate,  and  the  alkaline  liquid  separated. 
After  the  removal  of  the  ether  a  very  small  amount  (0-5  gramme) 
of  a  pale  yellow,  neutral  oil  was  obtained,  which  was  very  similar  in 
character  to  that  described  in  connection  with  the  ether  extract  of 
the  resin.  The  acid  extracted  from  the  ethereal  solution  of  the 
original  oily  liquid  by  means  of  sodium  carbonate  was  converted 
into  an  ammonium  salt,  from  which  two  fractions  of  silver  salt  were 
prepared  and  analyzed. 
(I)  0-0352  of  salt  gave  on  ignition  0  0132  Ag.    Ag  =  37  5 
(II)  0-0324"     "     "      "       "      0-0134  Ag.    Ag  =  41-4 
C9H1702  Ag  requires  Ag  =  40-7  per  cent. 
CnH2102  Ag       «      Ag  =  36-9   <i  « 
The  acids  remaining  in  the  aqueous  distillate  after  extraction  with 
ether  were  converted  into  a  barium  salt,  of  which  about  I  gramme  was 
obtained.  This  gave  reactions  indicating  the  presence  of  formic  and 
butyric  acids. 
After  the  removal  of  the  above  described  volatile  products  by 
distillation  with  steam,  there  remained  in  the  distillation  flask  a 
