CIRCULATION OF THE BLOOD. 79 
effect on the trace of the auricular contraction, and to make the thus 
taken trace deficient in the rise which at other times results from that 
contraction. Atall events if this assumption be made, itis found that 
the lengths of the different parts of the beat are not influenced by 
posture, and they agree exactly with the above-stated law. 
The following are measurements made since the publication of the 
original paper, which tend fully to confirm the above statement :— 
vce | Tames | ict, 
the first ° Ww. 
is eeactend ta the beat on formula 
whole beat. ay = 24/2: 
46 2°925 2°93 
43 2-8, 2°88 2-885 
49 2°85 2-86 
52°5 2°71 2-765 
56 2°63 2°675 
57 2-75 2-66 
58 2°65 2-625 
60 2°63 2°59 
64°5 2-556 2-49 
69 2°45 2-4 
74 2°28 2-325 
79 2°23, 2-275 2°24 
80 2 -24375, 2-207 2°225 
81°5 2-2, 2°185, 2-093 2-2 
St 2-105 2°175 
85 2°09 2°16 
86 2-17, 2-053 2-155 
88°5 2-245, 2-275 2-11 
905 2-062 2-1 
92 2°12 2°09 
< 92 2 -0875 2-08 
94 2°14125 2°05 
Prop. Il. The length of the interval between the commencement Page 142. 
of the primary and the dicrotic rises in the radial artery is constant 
for any given pulse-rate, and varies as the cube root of the length of 
the pulse-beat—being found from the equation zy’ = 47 3/z, where 
2 = the pulse-rate and y’ = the ratio borne by the above-named part 
to the whole beat. 
This law was enunciated in the paper before referred to as read 
before this Society by myself, and published in its ‘‘ Proceedings” 
(XVIII. p. 351).* Since that paper was read a fresh series of 
measurements have strongly confirmed its accuracy, and practice in 
manipulation has diminished my limits of experimental error so far 
that a difference of 5 per cent. from the calculated results is rarely 
found. 
* Supra, p. 14. 
