The  method  may  be  conveniently  em-
ployed for  determining  roughly  the  propor-
tion of  oil  in  the  reserve  food  of  the  castor-
oil  seed,  for  example.
A  number  of  seeds,  freed  from  their
testas,  are  carefully  weighed  and  one  by  one
are  broken  up  in  a  perfectly  clean  glass
basin  with  the  well-rounded  end  of  a  glass
rod.  The  material  is  then  dropped  into
the  thimble ;  any  particles  adhering  to  the
basin  or  rod  must  be  carefully  removed  by
means  of  a  platinum  wire  and  also  placed
FIG.  i.  in  the  thimble.
The  basin  and  glass  rod  should  then  be  carefully  washed
with  a  few  drops  of  ether  to  remove  the  last  traces  of  fat,  and
the  resulting  solution  should  be  added  to  the  broken-up  seeds
in  the  thimble,  care  being  taken  not  to  employ  enough  ether
for  the  solution  to  trickle  through  the  thimble.
