PART II. GOOD HEALTH IN THE 



HOME 



CHAPTER IV 

 PURE AIR 



Problems. i. To understand how and why we breathe 

 air. 



2. To understand the need of ventilation and how to ven- 

 tilate our rooms. 



Experiments. i. Does air have weight? 



2. To illustrate the process of breathing. 



3. To determine some products of respiration. 



4. To demonstrate .the principles involved hi ventilation. 



Project I. CAN I INCREASE MY LUNG CAPACITY WITHIN TEN 



WEEKS ? 



1. What is my chest expansion at the present time? 

 Take measure under the arms, clothing removed. 



(1) After taking a good normal breath. 



(2) After exhaling a normal breath. 



(3) After filling the lungs as full as possible. 



(4) After forcing all the air possible from the lungs. 

 The difference between (3) and (4) is the chest expansion. 



2. Make a tabular form for recording these four measurements 

 and the chest expansion. Take weekly measurements for ten weeks. 



3. Find out what exercise is good to develop the lungs and prac- 

 tice it faithfully each day. 



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