526        Recent  Literature  Relating  to  Pharmacy.  {Am6ciXrPih8t8.m- 
glycyrrhizin  from  air-dried  Russian  licorice  root.  The  researches 
are  to  be  continued. 
TEST  FOR  COTTON-SEED  OIL. 
G.  Marpurgo  (Schweiz.  Woch.  f.  Chem.  u.  Pharm.,  1898,  p.  184) 
has  experimented  with  the  new  method  for  detecting  cotton-seed 
oil  in  oil  mixtures,  as  given  by  Fortelli  Ruggeri  (Selmi,  1898,  p.  1). 
The  method  (Schzveiz.  Woch.  f.  Chem.  u.  Pharm.,  1898,  194)  is  as 
follows:  5  grammes  of  the  oil  is  mixed  with  30  c.c.  of  a  6  per 
cent,  alcoholic  KOH  solution  and  saponified  at  a  comparatively  low 
temperature.  It  is  neutralized  with  acetic  acid,  using  two  drops  of 
a  phenolphthalein  solution  as  an  indicator.  After  this,  it  is  saponi- 
fied with  a  10  per  cent,  neutral  lead  acetate  solution.  The  soap  is 
washed  with  lukewarm  water,  dried  on  filter  paper  and  treated  with 
100  c.c.  ether  in  a  flask  connected  with  a  reflux  condenser.  It  is 
heated  for  a  few  minutes  and  then  allowed  to  stand  for  a  half  hour. 
The  lead  salts  of  the  stable  fatty  acids  separate  and  are  removed 
from  the  ethereal  solution.  The  latter  is  treated  with  HC1  in  a 
separating  vessel  and  freed  from  lead.  The  ethereal  solution  is 
washed  with  water  until  all  traces  of  acid  are  removed  and  then  fil- 
tered and  distilled.  The  residue  from  the  distillation  is  taken  up 
with  10  c.c.  of  90  per  cent,  alcohol  and  treated  in  a  test-tube  with 
1  c.c.  of  a  5  per  cent,  aqueous  silver  nitrate  solution  and  heated  to 
6o°-8o°  C.  on  a  water-bath.  If  there  was  no  cotton-seed  oil 
present,  the  solution  is  clear  from  one-quarter  hour  to  one  hour.  If 
cotton-seed  oil  is  present,  the  solution  becomes  dark  and  blackens 
and  deposits  a  black  precipitate.  This  reaction  is  characteristic  for 
admixtures  of  i~5  per  cent,  of  cotton-seed  oil,  and  is  characteristic 
for  this  oil  alone. 
The  author  also  experimented  satisfactorily  with  the  method  of 
Cavalli,  using  resorcin,  given  in  Selmi,  1897,  p.  113. 
SPIRITUS  SAPONATUS. 
For  the  preparation  of  spirit  of  soap  in  the  cold,  L.  Meissen 
[Pharm.  Zeit.,  1898,  p.  254)  proceeds  as  follows:  10-5  parts  of  melted 
KOH  are  dissolved  in  50  parts  of  alcohol;  to  this  is  added  60  parts 
of  olive  oil.  The  saponification  occurs  in  a  few  hours,  with  occa- 
sional shaking  of  the  mixture.  After  this,  250  parts  of  alcohol, 
and  then  230  parts  of  water  are  added,  and  the  spirit  filtered. - 
Chem.  Zeit.y  1898,  p.  119. 
