CHAPTER VI 

 COMPOSITION OF THE AIR ATOMIC THEORY 



64. Questions for Discussion. 1. Will a lamp burn if the top of 

 the chimney is closed ? 2. Why are there holes in the base of the 

 burner of a lamp or lantern? 3. How does the kerosene or candle oil 

 reach the flame ? 4. Is there a nonluminous portion in the flame of a 

 kerosene lamp? in a gas flame? 5. What should be done to correct 

 a smoking lamp chimney ? 6. Why does a person hold his hand around 

 a match when he first lights it? Is similar protection needed when 

 starting a wood or coal fire ? in starting a gas tin- ? 7. Why is the 

 flame of a lamp or candle driven upward? 8. Why is it dangerous to 

 pour gasoline in a room where there is a flame? 9. How do you 

 explain the presence of water on the inside of a lamp chimney im- 

 mediately after lighting the lamp? Why does this water later dis- 

 appear? 10. Would kerosene or gas flames used for lighting affect 

 the need for ventilation in a room? 11. Why does carbon dioxide 

 sometimes remain in wells or cisterns when most gases would escape? 

 Why do workmen lower a lighted lantern into an old well before 

 they descend into it? 12. Why is carbon dioxide valuable for use 

 in fire extinguishers? 13. It is said that the first thing to do in case 

 a person's clothes catch fire is to cover the person with a blanket or 

 robe. Why? 14. Why do iron fences rust? How may we prevent 

 objects from rusting? 



65. The air not a simple substance. When you consider 

 what we have learned about the air in connection with pre- 

 ceding chapters, you may recall several facts which have 

 shown that the air is not composed of one substance only. 

 For instance, we found that water vapor is often a very 

 considerable part of the air. The air is in fact a mixture 

 of several gases, of which water vapor is one. We should 

 get some acquaintance with at least the more important of 

 these and learn how they act. As a means of securing such 



