470  Glycyrrhizin  in  Licorice  Root.        j  ^^jufy^i^r .arm" 
volume  of  water,  saturated  with  potassium  hydrate,  and  made  up  to 
500  cc.  in  a  volumetric  flask. 
"One  hundred  cc.  of  the  solution  are  evaporated  in  a  weighed 
dish,  and  dried  to  constant  weight  at  a  no°.  Another  100  cc.  are 
precipitated  hot  with  barium  chloride,  filtered,  and  washed  on  a  tared 
filter,  dried  at  a  no°,  and  weighed. 
"The  amount  of  glycyrrhizin  in  2  g.  licorice  extract  is  obtained 
by  calculating  the  barium  sulphate  to  potassium  sulphate,  and  sub- 
tracting that  amount  from  the  quantity  representing  the  mixture  of 
neutral  potassium  glycyrrhizinate  and  potassium  sulphate,  and  fur- 
ther subtraction  of  11.58  per  cent,  for  the  amount  of  potassium  in 
the  salt." 
[Translator's  Note. — Linz  shows  that  pieces  of  "roughly 
powdered  licorice  extract"  are  not  penetrated  by  the  sulphuric-alco- 
hol mixture  even  after  one  and  a  half  days,  or  even  after  several 
hours  warming.  In  spite  of  using  finely  powdered  material,  he  ob- 
tained 59-60  per  cent,  insoluble  residue.  Linz  further  shows  that 
considerable  loss  results  from  precipitating  glycyrrhizin  from  the 
excessive  volume. 
Linz  demonstrates  that  Cederberg's  barium  chloride  precipita- 
tion is  open  to  serious  objection,  and  is  not  practical,  unless  modi- 
fied. With  the  necessary  modification,  he  obtained  the  results  11.59, 
11.75,  11 -9  Per  cent,  glycyrrhizic  acid.    (P.  A.  H.)] 
Linz  continues : 
''Cederberg's  method  is  undoubtedly  interesting  and  original. 
But  his  method  requires  a  long  time,  and  weighings  which  are  not 
simple,  and  also  uses  more  than  half  a  liter  of  alcohol  for  every 
glycyrrhizin  determination.  The  values  obtained  are  higher  than 
others,  because  he  includes  in  the  weight  much  impurity.  In  addi- 
tion to  this,  the  losses  of  glycyrrhizin  are  high,  but  I  have  been  un- 
able to  establish  their  amount,  even  approximately.    .   .  . 
"Taking  into  account  the  fact  that  in  spite  of  a  roundabout 
analytical  method,  one  obtains  results  which  are  too  high  on  account 
of  gross  impurity  of  the  weighed  acid,  and  further  that  the  losses  of 
glycyrrhizic  acid  are  not  inconsiderable,  one  cannot  hail  Cederberg's 
method  in  the  form  given,  as  an  improvement." 
