26 



THE OCEAN OF AIR 



homes and public buildings such as theaters have been 

 equipped with machinery to condition the air which is 

 used in them. Air conditioning means the controlling 

 of the conditions of air which make for comfort and 

 good health. 



In the past almost the only attempt to condition the 

 air of our homes was to heat it in the winter time. In 

 the newer process the air is not only heated in winter 

 and cooled in summer but is washed free of dust and 

 is given the proper amount of moisture content for 

 good health. In a later unit of this book you will learn 

 how this is accomplished as you study the devices 

 used for heating homes. 



REFERENCES FOR FURTHER STUDY 



Caldwell and Curtis, Science for Today, pp. 27-38 



Clement, Collister, and Thu/ston, Our Surroundings, pp. 34- 



35 



Hunter and Whitman, My Own Science Problems, pp. 67-72 

 Lake, Harley, and Welton, Exploring the World of Science, 



pp. 38-47 

 Pieper and Beauchamp, Everyday Problems in Science, pp. 



225-233 

 Powers, Neuner, and Bruner, T,ie World around Us, Chaps. 



11-14; Man's Control of His Environment, pp. 601-611 

 Van Buskirk and Smith, The Science of Everyday Life, pp. 



42-46 

 Watkins and Bedell, General Science for Today, pp. 4-5 and 



275-278 



Webb and Beauchamp, Science by Observation and Experi- 

 ment, pp. 223-227 

 Wood and Carpenter, Our Environment: How We Use and 



Control It, pp. 141-176 



WHAT YOU SHOULD AIM TO ACQUIRE FROM 

 THIS STUDY 



1. Something of the make-up of the air and the 

 chemical nature of its important parts. 



2. The meaning of the terms burning and oxidation, 



3. The difference between physical and chemical 

 changes. 



4. The importance of air to the life processes of 

 plants and animals. 



5. The importance of good ventilation to health, 

 and the best methods of securing it. 



TEST OF MASTERY OF THE TOPIC 



In your notebook complete the statements, answer the 

 questions, and comply with the instructions. 



1. Of what three elements is air chiefly composed? 



2. A test for the presence of oxygen is to thrust a 



into a jar believed to contain oxygen. 



3. When a can rusts the (iron, tin) of which it is 



made has united with the (air, oxygen) of the air to 



form (an oxide, water) 



4. The rusting of a can is oxidation, while the burn- 

 ing of a candle is oxidation. 



5. Oxygen may be prepared by heating a mixture of 



and 



6. The of clear is a test for carbon dioxide. 



7. Carbon dioxide may be prepared in the laboratory by 

 the action of - on 



8. What changes take place when a substance burns? 

 Explain each change. 



9. Smoke is gases and fine material carried from 



the fuel. 



10. What happens to the nitrogen in the air when a sub- 

 stance burns? 



11. Why does the air not become filled with carbon 

 dioxide which is given out by all living things and most 

 things that burn? 



12. What are the important things to remember in ventilat- 

 ing a room? 



13. By means of a drawing show your sleeping room and 

 how you secure your ventilation. Is your room properly 

 ventilated ? 



SUPPLEMENTARY MATERIALS 



Reading suggestions 



Clarke, The Boys' Book of Chemistry (Button) 

 Collins, Wonders of Chemistry (Crowell) 

 Collins, Boy's Book of Experiments (Crowell) 

 Fournier D'Albe, Wonders of Physical Science (Mac- 



millan) 



Bond, On the Battle Front of Engineering (Century) 

 Cochrane, Wonders of Modern Mechanism (Lippin- 



cott) 



Moffett, Careers of Danger and Daring (Century) 

 Corbin, The Romance of Submarine Engineering 



(Lippincott) 



Bragg, The World of Sound (Button) 

 Bond, With the Men Who Do Things (Scientific 



American) 



Davis, The Advance of Science (Doubleday) 

 Fisk, Exploring the Upper Atmosphere (Oxford) 



Talman, The Realm of the Air (Goodheart) 

 Riesbeck, Air Conditioning (Bobbs) 



Reports which may be prepared 



1. Exploration of the upper atmosphere 



2. Historic altitude flights of airplanes and bal- 

 loons 



3. The history of pumps 



4. The uses of compressed air 



5. An hour in a caisson 



6. Building a tunnel under a river 



7. The discovery of the air brake 



8. The building of a subway 



9. Working under water 



10. The musical instruments of primitive people 



11. Sounds of the world about us 



12. Sound in music 



13. The first balloon ascension 



