Experimental researches on the influence exercised by atmospheric pressure upon the progression of the blood in the veins : upon that function called absorption, and upon the prevention and cure of the symptoms caused by the bites of rabid or venomous animals / With ... the original reports of Baron Cuvier and of Profs. Dumeril and Laennec. By David Barry.

  • Barry, David, Sir, 1780-1835
Date:
1826
Catalogue details

Licence: Public Domain Mark

Credit: Experimental researches on the influence exercised by atmospheric pressure upon the progression of the blood in the veins : upon that function called absorption, and upon the prevention and cure of the symptoms caused by the bites of rabid or venomous animals / With ... the original reports of Baron Cuvier and of Profs. Dumeril and Laennec. By David Barry. Source: Wellcome Collection.

    39/192 (page 23)
    Since it is evident that the blood sent into the aorta cannot arrive through any other channel than the pulmonary veins, it will not be un¬ reasonable to conclude, either that the lungs must be equally pervious to the blood of the right heart during all the stages of respiration, or, that if they are not so, there must be a reservoir from which the left heart can be supplied during the period when they are least pervious. The lungs themselves are placed within two ca¬ vities, which, as we have just seen, are in a state of tendency towards the formation of a vacuum during the act of inspiration, and therefore the pulmonary veins would, at first sight, appear to be all equally exempt from pressure in every part of the thorax, at the moment of its expansion. A more attentive examination, however, will shew, that nature has ensured, by a beautiful and simple mechanism, as constant and as ample a supply to the left heart, as she has to the right, and by the same means ; viz., atmospheric pressure. I shall take the thorax of the horse as an example to illustrate the pulmonary venous circulation in the warm-blooded mammalia.