HYGIENE OF RESPIRATION 169 



is confined to the diaphragm and abdomen, and lateral 

 action of the chest is suppressed. The effect of this is to 

 cause too great a displacement downward of the liver, 

 stomach, kidneys, colon, and other organs. But in nor- 

 mal or full breathing, any great degree of downward 

 movement is prevented by expansion of the trunk at the 

 waist. In abdominal breathing, the abdominal walls are 

 entirely relaxed as the diaphragm descends, and the 

 liver and other organs are moved but not compressed. 

 In full breathing they are compressed and slightly moved, 

 and the compression squeezes the blood out of them 

 toward the heart and presses the lymph upward through 

 the thoracic duct; the expansion of the chest at the 

 same time helps to draw the blood upward. During 

 expiration fresh blood is sent back to the abdominal 

 organs, and so they are kept fresh and strong. Ladies 

 who wear skirts with bands tight enough to support them 

 at the waist, and men who support their trousers by buc- 

 kling them around the waist, gradually lose the power of 

 lifting the ribs outward at the waist. This expansion is 

 most important for good breathing, because the lungs are 

 largest there. 



282. Effect of Alcohol upon the Lungs. It was learned 

 that alcohol paralyzes the vasomotor nerves, or those 

 that control the size of the blood vessels. This allows the 

 smaller arteries in the lungs to swell and the capillaries to 

 become congested, crowding upon the air cells and diminish- 

 ing the breathing power of the lungs, as is readily shown by 

 the use of the spirometer, a simple instrument which, when 

 the breath is blown into it, measures the number of cubic 

 inches the lungs expand. The continual congestion of the 

 lung tissue results in an abnormal growth of connective 

 tissue fibers in the walls of the cells ; the walls thus be- 

 come thickened and hardened and obstruct the absorption 

 of the oxygen and the escape of the carbon dioxid. Besides 



