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
_Third_.--"Reflex actions taking place through the sympathetic system
from one part of the body to another.--The contact of food with the
mucous membrane of the small intestine excites a peristaltic movement in
the muscular coat. The mutual action of the digestive, urinary, and
internal generative organs upon each other takes place entirely through
the medium of the sympathetic ganglia and their nerves. The variation of
the capillary circulation in different abdominal viscera, corresponding
with the state of activity or repose of their associated organs, are to
be referred to a similar nervous influence. These phenomena are not
accompanied by any consciousness on the part of the individual, nor by
any apparent intervention of the cerebro-spinal system."
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CHAPTER XIII.
THE SPECIAL SENSES.
SIGHT.
The eye is the organ through which we perceive, by the agency of light,
all the varied dimensions relations, positions, and visible qualities of
external objects.
The number, position, and perfection of the eyes, vary remarkably in
different orders, in many instances corresponding to the mode of life,
habitation, and food of the animal. A skillful anatomist may ascertain
by the peculiar formation of the eye, without reference to the general
physical structure, in what element the animal lives. Sight is one of
the most perfect of the senses, and reveals to man the beauties of
creation. The aesthetic sentiment is acknowledged to be the most
refining element of civilized life. Painting, sculpture, architecture,
and all the scenes of nature, from a tiny way-side flower to a Niagara,
are subjects in which the poet's eye sees rare beauties to mirror forth
in the rhythm of immortal verse.
In the vertebrates, the organs of vision are supplied with filaments
from the second pair of cranial nerves. In mammalia, the eyes are
limited to two in number, which in man are placed in circular cavities
of the skull, beneath the anterior lobes of the cerebrum. Three
membranes form the lining of this inner sphere of the eye, called
respectively the Sclerotic, Choroid, and Retina.