546  Analysis  of Eriodictyon  Calif ornicum.  {hm^;^!ak' 
filtrates  with  animal  charcoal,  evaporating  and  exsiccating  over  sulphuric 
acid,  a  brittle  resin  was  separated  having  a  yellow-greenish  color,  slight 
acid  reaction,  aromatic,  acrid  slightly  bitter  taste,  faint  odor,  and  fusing 
at  about  the  temperature  of  boiling  water.  The  portion  left  undis- 
solved by  alcohol  of  70  per  cent,  was  treated  with  hot  alcohol  of  95 
per  cent.,  as  long  as  this  dissolved  any  of  the  material. 
A  grayish  soft  and  tenacious  substance  was  left,  not  volatile,  oh 
stronger  heating  fusing  and  burning  with  a  smoky  flame,  destitute  of 
taste  and  odor,  insoluble  in  alcohol,  partially  soluble  in  petroleum  naph- 
tha, ether  and  benzole,  readily  soluble  in  chloroform  and  in  a  mixture 
of  carbon  disulphide  and  absolute  alcohol,  which  facts  prove  its  iden- 
tity with  caoutchouc.  From  the  hot  alcoholic  solution,  on  cooling,  a 
soft  waxy  substance  separated,  forming  a  pellicle  ;  this  substance,  freed 
from  adhering  resin  by  continued  washing  with  cold  alcohol,  possesses 
a  greenish-white  color,  proven  to  be  a  vegetable  wax.  The  quantity 
obtained  was  too  small  to  permit  a  closer  study  of  its  properties.  The 
remaining  alcoholic  liquid  was  of  a  dark  green  color,  possessing  no 
peculiar  taste  or  odor,  and  was  completely  decolorized  by  animal  char- 
coal, and  could  not  be  regarded  as  a  resin  proper  but  as  inert  coloring 
matter. 
B.  Examination  of  the  Aqueous  Liquid. — No  crystallizable  substance 
was  obtained,  and  on  application  of  the  proper  tests  no  indication  of  an 
alkaloid  or  nitrogenous  compound  was  obtained.  The  acid  found 
present  in  small  quantity  proved  to  be  a  tannic  acid  precipitated  by 
ferric  chloride,  almost  black  in  color. 
2.  The  alcoholic  percolate  was  evaporated  to  a  small  bulk  and  mixed 
with  water. 
The  insoluble  resinous  portion  obtained  consisted  entirely  of  color- 
ing matter,  its  alcoholic  solution  being  without  taste  or  odor,  was  en- 
tirely decolorized  by  animal  charcoal. 
A  portion  of  the  aqueous  liquid,  after  being  entirely  freed  from 
resinous  coloring  matter,  was  concentrated  by  slow  evaporation  and 
left  on  ice  for  several  days.  It  yielded  no  crystals,  and  the  application 
of  alkaloid  tests  led  to  no  results.  To  be  firmly  convinced  on  this  point 
a  portion  of  the  liquid  was  digested  with  oxide  of  lead  to  remove  tan- 
nic acid,  the  filtrate  evaporated  to  dryness  and  extracted  with  hot 
alcohol  of  95  per  cent.  ;  the  solution  on  spontaneous  evaporation  left 
