Experiments and observations on the sounds of the heart / by Robert Spittal.

  • Spittal Robert.
Date:
[1836?]
Catalogue details

Licence: Public Domain Mark

Credit: Experiments and observations on the sounds of the heart / by Robert Spittal. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    In answer to the first query, I again refer to the preceding ex periments, in the account of which it is stated, that the degree of force required for the production of sound was very slight, and that a considerable sound resulted from the simple approximation of the point of the finger or apex of the heart, if of sufficient firmness, to the parietes of the thorax. That there is ample space in the human body for the heart to advance and retire from the walls of the chest, in the manner supposed by Magendie, ap- pears not only from the foregoing observations, but likewise from the following consideration, viz. that the heart does not entire- ly occupy the pericardium, but is contained loosely in that en- velope. But even this does not seem to be absolutely necessary to the motion of the organ, and in cases of universal adhesion of the pericardium to the heart, it appears to me quite possible for the organ,—projecting as it does into the left cavity of the pleura, and considering at the same time the great looseness of the cel- lular connections of the pericardium in the mediastinum,—to be tilted forwards and upwards, and to produce percussion of the thorax. And in such cases, we have not only the two sounds, but an impulse accompanying the first. I do not here allude to recent cases of pericarditis. The amount of force required to produce sound in the dead body we have seen to be very small; and from the purely phy- sical nature of the phenomenon, we have every reason to expect the same results from similar causes in the living body. Now, from frequent observation on dogs, I have not the slightest hesi- tation in stating, that the degree of impulse is considerably greater than was amply sufficient for the production of sound in the ex- periments previously recorded; and there is reason to believe, from comparative observations on these animals entire, and on the living human body, that the impulse of the heart is always stronger in the latter. That the heart generally advances to, and retires to a certain extent from, the walls of the thorax during its action, may be con- sidered as proved; but that it always takes place to the extent implied by the statements of Magendie, I think, may be question- ed ; at all events, from the following ob.servations, this does not appear to be in all cases essential for the production of a certain degree of impulse. For example, in detailing one of his experi- ments, Dr Williams remarks, that at each systole, the sudden tension or tighteningof theventricleswas felt by the finger applied to their body, as an abrupt shock, with which the first sound exact- ly coincided.* And in an experiment on a dog performed last July, I find it stated in my notes, that while the finger was inclose
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