10 GOOD HEALTH 



somewhere, or from food or meat that is spoiling. Such 

 things should never be left where they can change the air. 



In some cities more people die in one part than in 

 another, and often the whole trouble comes from impure 

 air. Those who breathe it are not as strong as they 

 would be if they breathed only pure air, and on this 

 account it is easy for them to become ill. Worse yet, 

 when such people are once ill, if they have to keep on 

 breathing the impure air, they are far more likely to 

 die than if they were breathing pure air. 



Let us do all we can to breathe pure air every day, so 

 that we may feel well and be well, and learn our lessons 

 with as little trouble as possible. 



QUESTIONS 



1. What difference does it make with our feelings whether we 

 sleep in pure air or impure air? 



2. Describe the two schoolrooms. 



3. If a room should be filled with animals, and if they should get 

 no fresh air, what would happen to them? 



4. What do leaves take from the air ? 



5. What do plants do with carbon dioxid ? 



6. Which gases do plants use in breathing ? 



7. How can you show that a candle uses up oxygen? 



8. How much more oxygen does one gas jet use than one man? 



9. If a gas jet is open and not lighted, what harm does it do to 

 the air of a room? 



10. Why should we keep air free from smells of every kind? 



