250 
Method  of  Cleaning  Digitalis. 
/Am  Jour.  Pharm. 
<•       April,  19 18. 
(d)  Heating  on  platinum  foil  with  KOH  and  potassium  chlorate — 
green  color,  changed  to  purple  of  permanganates  upon  boil- 
ing with  water. 
Samples  of  soil  from  the  plots  from  which  the  digitalis  was 
grown  were  collected,  incinerated  and  tested  for  the  presence  of 
manganese  by  methods  as  given  afiove.    The  results  were  positive. 
Particular  attention  should  be  called  to  the  method  employed 
in  conducting  tests  "  c "  and  "  d."  When  a  considerable  quantity 
of  manganese  is  present  in  the  ash,  as  in  Stafford  Allen  and  Sons, 
English  digitalis,  or  in  digitalis  from  the  state  of  Washington,  only 
a  small  amount  of  KOH  and  potassium  chlorate  is  necessary  to  pro- 
duce the  characteristic  green  color,  however,  when  the  amount  of 
manganese  is  extremely  small  as  in  Minnesota  digitalis,  it  is  neces- 
sary to  use  larger  quantities  of  these  reagents,  in  order  to  observe 
the  reaction  satisfactorily. 
The  test  for  potassium  also  indicates  that  it  is  a  normal  con- 
stituent of  the  leaf.  On  account  of  the  excessive  cost  of  reagent 
potash  was  not  run  quantitatively. 
Percentage  of  Ash  Insoluble  in  HCL. — The  following  table 
clearly  indicates  that  the  9.284  per  cent,  of  ash  obtained  from  the 
clean  digitalis  by  screening  contained  but  very  little  foreign  matter, 
as  only  4.35  per  cent,  of  the  ash  was  insoluble  in  hydrochloric  acid. 
On  the  other  hand  nearly  two  thirds  of  the  screenings  ash  repre- 
sented material  insoluble  in  HQ.    This  quality  of  the  ash  is  even 
Table  VI. 
HCl  Insoluble  Ash  in  Digitalis. 
Material. 
Determi- 
nation. 
Percentage 
Ash  - 
Average. 
Percentage 
of  Ash  Insol. 
in  HCl. 
Percentage 
of  Ash  Insol. 
in  HCl— 
Average. 
I 
9.284* 
4-47 
4-35 
2 
4-23 
I 
26.24* 
60.45 
61.65 
2 
62.86 
I 
8-9I5t 
10.20 
9.41 
2 
io.i6f 
8.63 
I 
56.81 
70.98 
70.99 
2 
71.00 
*  Average  of  14  samples. 
f  No.  1,  Tailings ;  No.  2,  Middlings.  Samples  mixed  for  insol.  ash  de- 
terminations. 
