526        Recent  Literature  Relating  to  Pharmacy.  {Am6cioberPih898.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  (Schweiz.  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  HQ  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  1-5  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-  11 3 
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.,  1898,  p.  119. 
