Volume 1

The physiology of man : designed to represent the existing state of physiological science as applied to the functions of the human body / by Austin Flint.

  • Flint, Austin, 1836-1915.
Date:
1866-1874
Catalogue details

Licence: Public Domain Mark

Credit: The physiology of man : designed to represent the existing state of physiological science as applied to the functions of the human body / by Austin Flint. Source: Wellcome Collection.

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    material. These particles thus penetrate the lung substance, from which they can never be removed. They may find their way into the lymphatic vessels, bnt become fixed in the lymphatic glands, in which the quantity is always propor- tionate to that which exists in the lungs. It has been shown that the particles introduced under the skin in tattooing may also be taken up by the lymphatics, but are arrested and fixed in the glands.^ There is no ground for the hypothesis that the carbona- ceous matter of the lungs and bronchial glands is deposited as a residue of combustion of the hydrocarbons, in the process of respiration. Movements of Respiration. In man and the warm-blooded animals generally, the lungs attain their greatest degree of development, the sur- face which is exposed to the atmosphere is relatively great- est, and it is in these organs that nearly all of the process of interchange of gases takes place. In all animals of this class, inspiration takes place as a consequence of enlargement of the thoracic cavity, and the entrance of a quantity of air through the respiratory passages corresponding to the in- creased capacity of the lungs. In the mammalia, the chest is enlarged by the action of muscles; and in ordinary respi- ration, inspiration is an active process, while expiration is comparatively passive. In many birds, the chest is com- pressed by muscular action in expiration, and inspiration is efiected in a measure by elastic ligaments. In both classes, the air is drawn into the chest to supply the space produced by its enlargement. In some of the lower orders of animals which have no ribs or sternum, or in which the thorax is immovable and there exists no division between its cavity and the abdomen, the air is forced into the lungs by an act like deglutition. In these animals (frogs, lizards, turtles, ^ The results of the investigations of Robin are to be found in the Chimie Anatomique, by Robin and Verdeil, tome iii., p. 505 ei seq.