644 
DR. T. L. BRUNTON AND MR. W. PTE ON THE ACTION 
Table (continued). 
Time. 
Blood- 
pressure. 
Pulse in 
10 seconds. 
Oscilla- 
tions. 
Respi- 
ration. 
m. s. 
millims. 
millims. 
2 401 
Blood-pressure again lower. Diastole further pro- 
3 0 J 
longed 
45 
h 
30 
5 
Diastole 20 seconds. 
Systole 1 second. Diastolic curve slightly affected by 
respiration. 
3 401 
Blood-pressure recovering. Diastole shorter 
50 
2 
25 
9 
3 50/ 
Diastole 5 seconds. 
Systole | second. 
Respirations affect diastolic curve to extent of 3 mil- 
lims. 
4 0T 
Blood-pressure rising 
100 
4 
35 
10 
4 10/ 
Systole and diastole nearly equal. 
Both affected by respiration to extent of 4 millims. 
4 20 1 
Blood-pressure nearly at the height of commence- 
4 30] 
ment of experiments. Systole sharp 
130 
5 
35 
4 401 
Blood-pressure higher. Diastole again prolonged . . 
140 
2\ 
60 
10 
4 50/ 
Diastole 4 seconds. 
Systole g second. 
Respirations affect curves to extent of 10 millims. 
5 20 1 
There was again a fall of blood-pressure with great 
5 30/ 
prolongation of diastole similar to that which 
occurred at 2.5' to 2.20, but less marked 
115 
1 
50 
9 
6 0\ 
6 10/ 
Do., more marked 
80 
1 
30 
4 
6 20/ 
Gradual fall of blood-pressure. Cessation of heart’s 
7 30/ 
action. 
Post mortem (immediately after death). — The heart contained blood, and contracted 
on puncture. The auricles contracted for three minutes after death. 
This experiment shows that the action of a small dose of casca is to raise the blood- 
pressure and slow the heart at first. Next, when the heart becomes very slow, the 
pressure falls, and finally the heart ceases to beat and death takes place. 
The cardiac pulsations remained slow from the time of the injection of the casca up till 
death ; and although they at one time rose from 1 pulsation in 30 seconds up to 5 pulsa- 
tions in 10 seconds, they never came at all near to Ihe normal, which in this animal 
was 18^ pulsations in 10 seconds. 
The very slow pulse here indicates that the vagus is probably stimulated by the casca ; 
and the continuance of the blood-pressure at the height of 65 millims., during a cardiac 
diastole, lasting for 30 seconds, shows unmistakably that the arterioles are strongly 
contracted by the drug. 
Action on Vagus. 
Maximum Irritation. 
Experiment XXXV. — March 4. 
A cat, weight 4 lb., was chloroformed, and a cannula was placed in the left carotid 
artery and in the left femoral vein. 
