""^"'■Tine''i88o^™"}      Commercid  Extract  of  Kramer ia.  297 
As  the  quality  of  krameria  depends  upon  the  tannin  present,  it  was 
determined  by  the  gelatin  test.  One  drachm  of  the  finest  gelatin  was 
•dissolved  in  4  ounces  of  hot  distilled  water,  and  15  grains  of  powdered 
alum  added.  By  experimenting,  I  found  that  31  drops^  of  this  gelatin 
solution  would  precipitate  i  grain  of  tannic  acid.  The  requisite  quan- 
tity of  the  gelatin  solution  was  added  to  the  cold  solutions  of  the 
extracts,  with  the  results  as  shown  in  the  table.  The  hot  solutions 
were  tested  for  tannin  in  like  manner,  and  found  to  yield  a  small  per- 
centage more  than  the  cold,  although  equally  as  varied. 
From  the  results  obtained  it  is  evident  that  manufacturers  have  very 
different  ways  of  making  the  extracts  of  krameria,  and  very  few,  if  any, 
adhere  strictly  to  the  formula  of  the  U.  S.  P.,  although  the  officinal 
formula  yields  a  stronger  and  much  more  soluble  extract. 
After  experimenting  with  hot  and  cold  water,  alcohol  and  a  mixture 
of  alcohol,  water  and  glycerin,  the  most  satisfactory  results  were 
obtained  by  the  following  formula: 
Take  of    Krameria,  in  moderately  fine  powder,*       .     i6  troyounces 
Glycerin,  .  .  .  .}  troyounce 
Distilled  water,  .  .        a  sufficient  quantity 
Moisten  the  powder  with  5  fluidounces  of  the  distilled  water,  pre- 
viously mixed  with  the  glycerin.  Pack  it  firmly  in  a  conical  glass  per- 
colator, and  allow  it  to  macerate  for  48  hours  ;  then  gradually  pour 
distilled  water  upon  it  until  the  drug  is  exhausted ;  then  evaporate  the 
percolate  by  means  of  a  water-bath,  at  a  temperature  between  150^ 
and  lyO^F.,  to  the  consistency  of  an  extract. 
The  extract,  weighing  9  per  cent,  of  the  powdered  root,  is  completely 
soluble  in  cold  and  hot  water,  and  indicates  31  per  cent,  of  tannin. 
The  following  table  shows  the  amount  of  insoluble  matter  in  some 
commercial  extracts  of  krameria,  also  the  quantity  of  tannin: 
100  grains  Commercial  Extract  of  Krameria  contain^ 
Number  of  grs.  insoluble  matter  Number  of  grs.  insoluble  matter  \  't 
in  cold  distilled  water.  in  hot  distilled  water.  ^  °'  tannin,  ,rs 
A  24  21J  18^^ 
B  43  37  i6,V 
<^  59?  53  lo? 
D  67J  63  8 
E  76^  71-2  7 
F  81  74I.  6  J 
G  88  84I  sk 
H  86  84  4i 
Drops  are  a  very  unsatisfactory  measure  for  quantitative  determinations. — Ed. 
