610  Gleanings  from  the  German  Journals.  {%JS,riSai,m' 
and  a  pure  oil  at  times  fails  to  produce  them.  The  acidity  of  the  oils 
gives  important  information  as  to  the  presence  of  rosin  and  is  best 
determined  by  dissolving  2  gm.  oil  in  30  cc.  alcohol,  adding  a  few 
drops  of  phenolphthaleine  and  titrating  with  alcoholic  potassium 
hydrate ;  the  number  of  milligrams  of  KOH  required  to  neutralize 
one  gram  oil  gives  the  acidity  figure. 
Pure  cassia  oil  (6  per  cent,  residue)  13 ;  this  was  not  changed  by 
passing  air  through  it  for  forty  hours.  Pure  Ceylon  oil  (2  per  cent, 
residue)  9  ;  another  sample  (2*5  per  cent,  residue)  10.  An  adulterated 
sample  of  cassia  oil  (28  per  cent,  residue)  47  ;  sample  of  cassia  oil  to 
which  20  per  cent,  rosin  had  been  added,  40.  Rosin  has  an  acidity 
figure  of  150.  The  figures  just  quoted  render  the  method  an  import- 
ant one.— Chemilcer  Ztg.,  1889,  1406. 
Ricinin,  the  poisonous  principle  of  castor  oil  seeds,  is  not,  as  has 
been  claimed,  an  alkaloid,  but  is  an  albuminoid,  one  of  the  phytalbu- 
moses  and  belongs  to  the  class  of  unorganized  ferments.  Boiling  its 
solutions  almost  immediately  destroys  its  activity,  while  heated  dry  it 
is  not  easily  decomposed.  It  can  be  prepared  from  the  seeds  (after 
removing  the  integuments  and  the  oil)  by  percolating  with  a  10  per 
cent,  salt  solution.  The  percolate  is  saturated  with  sodium  and  mag- 
nesium sulphates  and  allowed  to  stand  in  the  cold,  when  besides  the 
double  salt  there  forms  a  white  precipitate,  easily  separated  from  the 
crystals,  which  is  filtered  off  and  transferred  to  a  dialyzer.  In  the 
dialysis  the  temperature  must  be  kept  sufficiently  low  to  prevent 
decomposition.  The  slimy  mass  is  scraped  from  the  septum  and  dried 
in  vacuo  over  sulphuric  acid ;  after  drying  the  masses  are  very  easily 
pulverized  and  yield  an  odorless  white  powder,  still  retaining  from 
10-20  per  cent,  ash  which,  however,  does  not  interfere  with  its  physio- 
logical action.  The  powder  can  be  preserved  for  long  periods ;  its 
best  solvent  is  a  10  per  cent,  salt  solution  which  for  experiments  can 
be  diluted  without  formation  of  an  immediate  precipitate.  The  vari- 
ties  of  Ricinus,  Croton  Tiglium  and  Jatropha  Curcas  all  appear  to 
contain  poisonous  albuminoids  which  are  similar,  if  not  identical. 
Attention  is  called  to  the  danger  arising  from  the  accumulation  of 
castor  oil  press-cakes  which  contain  a  substance  more  poisonons  than 
arsenic  (and  for  which  no  test  is  known)  and  which  can  so  easily  be 
obtained  by  any  one ;  the  suggestion  is  also  made  that  the  manufac- 
turers of  castor  oil  should  be  compelled  to  use  the  press-cakes  as  fuel 
as  soon  as  they  are  taken  out  of  the  press  or  else  to  mix  with  water 
