ber of mechanical devices, or machines, for causing a
variety of special movements.

2. The muscular system, which supplies the energy necessary for executing
the movements of the body.

3. The nervous system, which (_a_) controls and cooerdinates the various
activities and (_b_) provides for the _intelligent_ adjustment of the body
to its environment. (Review Summary of Part I, page 215, and consult Fig.
92, page 214.)

APPENDIX

*Equipment.*--Nearly all of the apparatus and materials called for in this
book may be found in the physical, chemical, and biological laboratories
of the average high school. There should be ready, however, for frequent
and convenient use, the following: One or more compound microscopes with
two-thirds and one-fifth inch objectives; a set of prepared and mounted
slides of the various tissues of the body; a set of dissecting
instruments, including bone forceps; a mounted human skeleton and a
manikin or a set of physiological charts; a set of simple chemical
apparatus including bottles, flasks, test tubes, and evaporating dishes;
and a Bunsen burner or some other means of supplying heat.

The few chemicals required may be obtained from a drug store or from the
chemical laboratory. Access to a work bench having a set of carpenter's
tools will enable one to prepare many simple pieces of apparatus as they
are needed.

*Physiological Charts* are easily prepared by teachers or pupils by
carefully enlarging the more important illustrations found in text-books
or by working out original sketches and diagrams. These, if drawn on heavy
Manila paper, may be hung on the wall as needed and preserved
indefinitely. By the use of colors, necessary contrasts are drawn and
emphasis placed on parts as desired. The author has for a number of years
used such home-made charts in his teaching and has found them quite
satisfactory. His plan has been to draw on heavy Manila paper, cut in
sizes of two by three feet, the general outline in pencil and then to mark
over this with the desired colors. There is of course an opportunity for
producing results that are artistic as well as practical, and if one has
time and artistic skill, better results can be obtained. Many of the cuts
in this book are excellently suited to enlargement and, if properly
executed, will provide a good set for general class purposes.

*Models.*--The use of prepared models of the different bodily organs is
strongly urged. These ma