Lectures on the diseases of the lungs and heart / By Thomas Davies.

  • Davies, Thomas, M.D.
Date:
1835
Catalogue details

Licence: Public Domain Mark

Credit: Lectures on the diseases of the lungs and heart / By Thomas Davies. Source: Wellcome Collection.

    42/558 (page 4)
    cular subject. In the first place, in the lungs you have a most delicate organisation, consisting of an immense number of cells, extremely thin, so that from their mere texture it is not a matter of sur- prise that these organs should become frequently affected. But when you superadd, that that tex- ture is in constant movement —a movement which commences at the moment of birth, and only ter- minates in an existence of longer or shorter dura- tion — a movement proceeding at the average rate of seventeen or eighteen respirations in a minute, and each of which, you will recollect, is not a sin- gle, but a double action, the one of inspiration, the other of expiration, so that you have no less than thirty-four or thirty-six movements going on in that time; — I say, therefore, that the frequency of these motions in so delicate a texture, must strongly predispose these organs to disease. Con- sider, also, the nature of the functions which the lung has to perform; on the one hand, receiving blood, varying frequently in quantity, varying in the force with which it is received from the heart, and varying also, doubtless, in its quality ; and on the other hand, receiving atmospheric air, varying also in quantity, quality, and, above all, in temper- ature ; — taking all these circumstances together, you see the numerous causes there are to account for the frequency of diseases of the lungs. The heart, again, is an organ delicate in its tex- ture, considering the function it has to perform. It has constantly to overcome a resistance, because its office is to propel forward a fluid; this office commencing at the earliest period of embryotic ex- istence, and terminating only in a life of varied