On the action of the heart, and a case of congenital fissure of the sternum (a) / by F.W. Pavy.

  • Pavy, F. W. (Frederick William), 1829-1911
Date:
[1857]
Catalogue details

Licence: Public Domain Mark

Credit: On the action of the heart, and a case of congenital fissure of the sternum (a) / by F.W. Pavy. Source: Wellcome Collection.

    1/8 (page 49)
    ■XTBAOT yaost THE MEDICAL TIMES AND GAZETTE, NOT, 21, 1857. ON THE ACTION OF THE HEART, AND A CASE OF CONGENITAL FISSURE OF THE STERNUM, (a) BY F, W. PAVY, M.D, I HAVE now, Gentlemen, to speak about the action of the heart, and, as I have told you, I propose to show you how it beats in an animal where the chest has been opened and the respiration is artificially maintained ; and afterwards to compare what we thus observe with what may be sean through the soft parietes of the chest, in the case of a foriegner now vis¬ iting our country, where nature has supplied us with an unusual exposure of this organ, by an arrest ot development of the chest-bone. By such a mode of treating our subject, I may inform you at once that we shall have to differ considerably from the description you may have read of the heart’s action in our ordinary works on Physiology. In the action of this organ, as you will presently see for yourselves, the corresponding cavities of the two sides accompany each other in contrac¬ ting and dilating But little force is demanded of the auricles, whilst great strength is required of the ventricles, as they have to overcome considerable resistance, aud form a most important consideration in maintaining the circulation, it must not, however, be overlooked that the action of the heart is not the only force in operation for keeping up the current of blood in the animal body. Plants have no hearts, and yet there is a circulation of their juices, in obedience to a definite arrange¬ ment. In some of the lower animals there is a circulation without the development of any special propelling organ to maintain it; and even in the embryonic condition of the hiahest. a definite movement of blood takes place before the heart is sufficiently developed to occasion it. What force is there, then, in these cases to establish a current, and what is there that causes the blood to move (as we may easily satisfy ourselves it does by the aid of the microscope, ( in the web of a frog’s foot, after the anin^al’s (a) From the Lectures ou Physiology delivered at Guy’s Hospital.