The aim in the preparation of this treatise on the human body has been,
first, to set forth in a _teachable_ manner the actual science of
physiology; and second, to present the facts of hygiene largely as
_applied physiology_. The view is held that "right living" consists in the
harmonious adjustment of one’s habits to the nature and plan of the body,
and that the best preparation for such living is a correct understanding
of the physical self. It is further held that the emphasizing of
physiology augments in no small degree the educative value of the subject,
greater opportunity being thus afforded for exercise of the reasoning
powers and for drill in the _modus operandi_ of natural forces. In the
study of physiology the facts of anatomy have a place, but in an
elementary course these should be restricted to such as are necessary for
revealing the general structure of the body.

Although no effort has been spared to bring this work within the
comprehension of the pupil, its success in the classroom will depend
largely upon the method of handling the subject by the teacher. It is
recommended, therefore, that the _relations_ which the different organs
and processes sustain to each other, and to the body as a whole, be given
special prominence. The pupil should be impressed with the essential unity
of the body and should see in the diversity of its activities the serving
of a common purpose. In creating such an impression the introductory
paragraphs at the beginning of many of the chapters and the summaries
throughout the book, as well as the general arrangement of the
subject-matter, will be found helpful.

Since the custom largely prevails of teaching physiology in advance of the
sciences upon which it rests—biology, physics, and chemistry—care should