Physiological observations on the pulsations of the heart, and on its diurnal revolution and excitability / by Dr. Knox.

  • Robert Knox
Date:
[1837?]
Catalogue details

Licence: Public Domain Mark

Credit: Physiological observations on the pulsations of the heart, and on its diurnal revolution and excitability / by Dr. Knox. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    vation of air to the lungs has on the pulse ; he ex])erimented on dogs, to ascertain the fact, and observed in himself that on emp- tying his lungs of air as much as he could, and then stopping his breath, the pulse became small and quick, with a kind of trembling convulsive motion, in less than half a minute of time. Finally, he compared the number of pulsations and inspira- tions together, and considered them to be in a minute, as fol- lows: Pulses, 65 72 116 Inspiration, 17 19 30 From these data I venture to draw the following conclusions : Ist, That Dr Bryan Robinson was the discoverer of the dif- ferential pulse in man that he described it perfectly, and as- cribed it to its real cause. 2dly, That he appreciated correctly enough the influence of food, and other disturbing causes of the heart's action, but that he knew nothing of the precise nature of the laws regulating these actions, not having submitted them to any statistical in- quiry. 3dly, He first suspected and proved indisputably, that from birth to adult age, the vapidity of the pulse constantly declines, and he has given an accurate statistical table to prove this. 4//t/?/, He endeavoured to show by the same nuraercial me- thod that the rapidity of the pulse was inversely as the height of the person ; or, to give an example, let A be 5 feet, and let B be 6 feet, then the pulse of A is to that of B. as 72 to 65. But this table is not carefully drawn up, and the conclusions are not legitimate. Sth/j/f He suspected a diurnal movement in the rapidity of the pulse ; viz. that it decreased during sleep, and increased from morning until night. With these and several other of his conclusions, I do not agree. We do not here discuss the accura- cy or legitimacy of Dr Robinson's conclusions generally, but sim- ply whether or not he was aware of the existence of certain laws respecting the physiology of the pulse, and of the influence of certain disturbing causes. Now nothing is clearer than that he was quite aware of these circumstances. Lastly, He attempted to ascertain statistically the effects of muscular motion on the pulse m Iwalth ; the ratio of the pulsa- tions to the inspirations and the immediate result on the heart's action, of a temporary deprivation of air.* With reference to any progress made in tliis inquiry from Robinson's time to my own I feel a delicacy in making any cri- tical observations. When I published my observations in the * Some observations were made on the pulse subsequent to those of Robinson, by Falconer and Hewron, but I have failed in procuring the works.