a circle.

The exercise is taken by causing the body to describe a complete
circle in the manner indicated in the cut. Little muscular effort is
required if the motion be rapid, because the momentum is sufficient to
carry the body around; but if the rotation be slow, more exertion is
required. This movement is specially adapted to the breathing powers
of weak persons, yet the most vigorous can readily get from it all the
exercise their chest and lungs require.

By means of these exercises the chest is gently but effectively
expanded in every direction and the elasticity of its walls promoted,
the air cells are expanded, and the lungs are rendered more permeable
to the respired air, and the strength of the respiratory muscles is
developed.

[Illustration: Fig. 3.]

Fig. 3 illustrates an exercise for the chest that is taken without any
apparatus other than an ordinary doorway. The exerciser should stand
in the position indicated in the engraving, and then step forward with
each foot alternately as far as possible without stretching the chest
too severely. The longer the step the more vigorous the exercise will
be.

[Illustration: Fig. 4.]

Fig. 4 shows an exercise taken between two chairs; the position
indicated in the cut having been assumed, the chest is then slowly
lowered and raised three to six times. This exercise is adapted to