The People's Common Sense Medical Adviser in Plain English: or, Medicine Simplified, 54th ed., One Million, Six Hundred; and Fifty Thousand — John Stuart Mill — John Shaqi
The People's Common Sense Medical Adviser in Plain English: or, Medicine Simplified, 54th ed., One Million, Six Hundred; and Fifty Thousand
John Stuart Mill · en
The venous blood is carried, as we have previously described, to the
right side of the heart and to the lungs, where it is converted into
arterial blood. It is now of uniform quality, ready to be distributed
throughout the body, and capable of sustaining life and nourishing the
tissues. Man breathes by means of lungs; but who can understand their
wonderful mechanism, so perfect in all its parts? Though every organ is
subservient to another, yet each has its own office to perform. The
minute air-cells are for the aeration of the blood; the larger bronchial
tubes ramify the lungs, and suffuse them with air; the trachea serves as
a passage for the air to and from the lungs, while at its upper
extremity is the larynx, which has been fitly called the organ of the
human voice. At its extremity we find a sort of shield, called the
_epiglottis_, the office of which is supposed to be to prevent the
intrusion of foreign bodies.
* * * * *
CHAPTER IX.
PHYSIOLOGICAL ANATOMY
THE SKIN.
Through digestion and respiration, the blood is continually supplied
with material for its renewal; and, while the nutritive constituents of
the food are retained to promote the growth of the body, those which are
useless or injurious are in various ways expelled. There are, perhaps,
few parts of the body more actively concerned in this removal than the
skin.
[Illustration: Fig. 46: An ideal
view of the papillae. 1, 1. Cutis vera.
2.2. Papillary layer. 3, 3. Arteries of the papillae.
4, 4. Nerves of the papillae. 5, 5. Veins of the papillae.]