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above. 2. There are three pairs of ribs below, while there are none above, but all ribs of the upper chest are ribs. 3. The lower of the joints between the seven pairs of true ribs and the sternum are more flexible than the upper joints because. (Observe the joints in Fig. 75.) 4. The walls of the waist swing and , while the walls of the upper chest must move and. 5. The bones of the rest upon the upper chest. In upper chest breathing their weight, and the weight of both of the must, therefore, be lifted. (Fig. 28.) Test by trying it.

. 77.

. 78.

. 79.

. Expansion at the waist is here impossible and the breathing is called "collar-bone breathing."

. Here, owing to pressure of clothing and faulty position, expansion of chest is hindered and breath is taken by the "abdominal method."

. Here the entire thorax can move freely, and natural breathing is the result. (For blackboard.) From Latson.

Hygienic Habits of Breathing.—Chest breathing uses chest chiefly, abdominal breathing uses abdomen chiefly, full breathing uses both. These three forms depend upon whether the breathing is carried on by using the muscles of (1) the chest, (2) the abdomen, or (3) both (see Figs. 77, 78, 79). There has been much debate among physicians, surgeons, and singers as to which of these methods is best. Probably this question would not have been raised but for the confining and deforming effect of clothing upon the waist. Full breathing is used