Am.  jour.^Pharm.  j  Stability  of  Digitalis  Leaf  Extracts. 
431 
Experimental. 
A.  Tincture  1.  No.  35337  (D-1625)  2-15-17.  A  standard 
U.  S.  P.  tincture,  alcohol  =  64  per  cent. 
Date. 
M.  S.  D.,  Mils. 
Toxicity,  Per  Cent. 
Period  in  Months. 
Mar.  2,  1917  
O.0061 
IOO 
Apr.  20,  1918  
O.0108 
55 
13 
Jul.  20,  1918  
0.0107 
55 
16 
Aug.  17,  1918  
0.0125 
48 
17 
Sep. 1,  1918  
0.0140 
42 
18 
Oct.  12,  1918  
0.0152 
37-5 
19 
Nov.  3,  1918  
0.0150 
40 
20 
Dec.  1,  1918  
0.0162 
37-5 
21 
Tincture  2.  No.  36498  (D-1625)  6-13-17.  Alcohol  =  64  per 
cent.    Assayed  as  follows  : 
Date.  M.  S.  D.,  Mils.       Toxicity,  Per  Cent.  \  Period  in  Months. 
June  19,  1917  !  0.0060  100.0 
July  21,  191 8   0.0120  50.0  13 
Aug.  17,  1918   0.0150  40.0  14 
Sept.  15,  1918  J  0.0160  37.5  15 
Oct.  13,  1918   0.0160  37.5  16 
Dec.  23,  1918  '  0.0160  37.5  18 
April  1,  1919  i  0.0160  37.5  22 
Tincture  3.  Fat  free.  No.  37798  (D-1625)  1-10-18.  Alcohol 
=  46  per  cent. 
Date. 
M.S.  D.,  Mils. 
Toxicity,  Per  Cent. 
Period  in  Months. 
Jan.  12,  1918  
0.0060 
100.0 
July  27,  1918  
O.OO93 
64.0 
6 
Aug.  31,  1918  
0.0120 
50.0 
7 
Sept.  28,  1918  
0.0150 
40.0 
8 
Oct.  20,  1918  
0.0l60 
37.5 
9 
Nov.  17,  1918  ,  
0.0160 
37-5 
10 
Tincture  4.  No.  38182  (D-1625  +  D-460)  1-31-18.  Alcohol 
=  64  per  cent.  This  tincture  when  first  prepared  showed  a  strength 
of  170  per  cent,  which  was  reduced  to  no  per  cent,  by  dilution. 
