Ana.  Jour.Pharra.  1 
December,  1896.  / 
Glycerite  of  Licorice. 
665 
the  licorice  extract  mixture  may  be  percolated  through  the  same 
sand-bed,  and  the  process  duplicated,  or  a  larger  sand-bed  may  be 
used  and  the  process  followed  on  a  larger  scale.  Doubtless,  work- 
ing on  an  extended  scale,  the  sand-bed  could  be  made  quite  large ; 
steam  heat,  with  a  vacuum  apparatus,  could  be  employed,  and 
working  details  could  be  profitably  modified. 
Ammonia  water  is  added  to  the  licorice  extract  mixture  to  bring 
into  solution  the  uncombined  glycyrrhizin  of  the  powdered  extract. 
The  excess  of  ammonia  water  is  eliminated  by  the  after-heating. 
The  success  of  the  process  depends  upon  the  manipulation  of  the 
sand-bed  and  the  carefulness  with  which  the  percolates  are  evapo- 
rated. To  prepare  the  sand  for  the  bed,  take  fairly  coarse  washed 
bar  sand,  and  remove  sticks,  stones,  etc.,  with  a  No.  20  sieve.  Clean 
the  sieved  portions  thoroughly  with  washings  of  boiling  water,  and 
dry,  heating  strongly.  To  make  the  bed,  place  a  flat  piece  of 
absorbent  cotton,  wetted  on  the  under  side,  in  the  bottom  of  the 
funnel  and  fill  the  latter  with  the  cleaned  sand  to  within  an  inch  or 
two  of  the  top.  If  a  larger  glass  funnel  be  used,  it  need  not  be  filled 
quite  so  full,  but,  to  a  degree,  the  broader  the  surface  of  the  sand- 
bed  used,  the  better  the  results. '  Percolation  commences  quickly, 
but  slows  up  in  a  short  time.  If  the  first  portions  of  percolate  be 
turbid,  they  should  be  returned  to  the  funnel. 
The  gelatinized,  starchy  mass  that  is  formed  upon  the  surface  of 
the  sand-bed  is  sometimes  an  inch  or  more  deep.  It  is  nearly  black 
from  the  presence  of  a  portion  of  the  soluble  principles  of  the  ex- 
tract. But  the  amount  of  the  latter  is  of  no  practical  moment,  and 
is  compensated  for  by  the  subsequent  standardization.  By  re- 
moving the  gelatinized  mass  before  continuing  percolation,  the 
latter  is  made  much  more  easy.  With  care,  the  same  sand-bed  may 
be  used  for  a  number  of  operations. 
With  the  formula  above  mentioned,  the  mixed  percolates  ob- 
tained by  the  writer  amounted  to  about  40  fluid  ounces.  More 
than  this  makes  no  practical  difference,  as  the  solution  is  standard- 
ized, but  it  is  desirable  to  have  as  small  a  volume  as  possible,  in 
order  to  diminish  the  time  of  evaporation,  and  reduce  the  danger 
of  an  empyreumatic  product. 
The  powdered  extracts  used  by  the  writer  averaged  40  per  cent, 
of  insoluble  matter.  The  amount  usually  allowed  by  manufacturers 
is  35  per  cent.,  but  the  percentage  varies  according  to  the  age  at 
