152  Digitalis  Thapsi  Lin.  { Am  l™{{ 
First  Experiment. 
Frog  pithed  and  stretched  out  on  board. 
Normal  heart  rate. 
9:  15  20  beats  in  20  seconds. 
9:  16  1  drop  tinct.  thapsi  drug  dropped  on  the  laid-bare  heart. 
9  :  20  20  beats  in  22  seconds. 
9:21  20  beats  in  23  seconds. 
9:  24  20  beats  in  26  seconds. 
9:25  2  drops,  same  solution. 
9:  28  20  beats  in  30  seconds. 
9  :  30  20  beat's  in  40  seconds. 
9:35  Beats  irregular  and  indistinct. 
9:40  Stopped  in  systole. 
Second  Experiment. 
Frog  pithed  and  fastened  to  board. 
Normal  heart  rate. 
10:  30  20  beats  in  24  seconds. 
10:  35  2  drops  tr.  digitalis  U.S. P. 
10 :  37  20  beats  in  28  seconds. 
10:  39  20  beats  in  30  seconds. 
10:45  20  beat's  in  30  seconds. 
10:46  2  drops,  same  solution. 
10:  50  20  beats  in  35  seconds. 
10:  55  20  beats  in  40  seconds. 
11 :  00  2  drops,  same  solution. 
11 :  05  20  beats  in  50  seconds. 
11 :  10  20  beats  in  55  seconds. 
Irregular  beat's  and  final  stoppage  in  systole. 
Third  Experiment. 
Normal  heart  rate. 
1 :  35  20  beats  in  20  seconds. 
1 :  40  2  drops  thapsi  drug  diluted,  1  in  3  from  the  tincture. 
1 :  45  20  beats  in  22  seconds. 
1 :  47  20  beats  in  23  seconds. 
2  drops,  same  solution. 
1 :  50  20  beats  in  28  seconds,  very  powerful. 
1 :  54  20  beats  in  30  seconds. 
1 :  55  2  drops,  same  solution. 
1 :  57  20  beats  in  33  seconds. 
2:00  20  beats  in  50  seconds. 
Very  irregular. 
2:  15  20  beats  in  200  seconds,  stopped  in  systole. 
