CHAPTER I - INTRODUCTION


To derive strength equal to the daily task; to experience the advantages
of health and avoid the pain, inconvenience, and danger of disease; to
live out contentedly and usefully the natural span of life: these are
problems that concern all people. They are, however, but different phases
of one great problem—the problem of properly managing or caring for the
body. To supply knowledge necessary to the solution of this problem is the
chief reason why the body is studied in our public schools.

*Divisions of the Subject.*—The body is studied from three standpoints:
structure, use of parts, and care or management. This causes the main
subject to be considered under three heads, known as anatomy, physiology,
and hygiene.

_Anatomy_ treats of the construction of the body—the parts which compose
it, what they are like, and where located. Its main divisions are known as
gross anatomy and histology. _Gross anatomy_ treats of the larger
structures of the body, while _histology_ treats of the minute structures
of which these are composed—parts too small to be seen with the naked eye
and which have to be studied with the aid of the microscope.

_Physiology_ treats of the function, or use, of the different parts of the
body—the work which the parts do and how they do it—and of their relations
to one another and to the body as a whole.

_Hygiene_ treats of the proper care or management of the body. In a
somewhat narrower sense it treats of the "laws of health." Hygiene is said
to be _personal_, when applied by the individual to his own body;