610 Our Surroundings 



10. Name several subjects which you would like to see broadcast by means 

 of television. 



11. How could you telephone across the ocean? 



12. Why do you suppose it is more expensive to telephone from New York 

 to London than from New York to San Francisco, which is even 

 farther away? 



13. How does radio help make air travel safer? 



14. Describe a situation in which an air liner might be saved by a radio 

 beacon from destruction. 



15. What is the difference between a searchlight and a floodlight? Name 

 some uses of each. 



16. Describe the four steps in converting fuel oil to flame in an oil burner. 



17. How is gas used in heating? 



18. Tell how an electric furnace operates. 



19. Complete the following statements orally : 



(a) A thermostat is a device to regulate the 



(b) A humidistat is a device to regulate the 



20. How is dry ice made? Why is it more efficient than water ice? What 

 special uses has it? 



21. What is meant by air conditioning? 



22. Describe the system of air conditioning in a theater. 



23. What is the advantage of washing, or filtering, the air that we breathe ? 



24. Describe a gyroscope. What remarkable qualities has it? 



25. Name some of the uses of the gyroscope. 



26. Can you think of any other way in which the gyroscope may be put 

 to practical use? If so, describe it. 



27. The steamship Mauretcmia has a long sharp bow and the Europa has 

 a rounded bow. Which boat do you think is faster? Why? 



PROJECTS 



1. Bring to class a piece of moving-picture film, including a sound strip. 

 Explain its use. 



2. Bring to class a picture which has been sent by telephotography. 

 Examine it closely and explain its appearance. 



3. Write a composition or plan a talk on what important effects air con- 

 ditioning may have in the future. 



4. Obtain a toy gyroscope and experiment with it. 



5. Carve a model of a streamlined airplane or racing car. Explain to the 

 class the advantages of its shape. 



OUTDOOR OBSERVATION 



1. Watch for the next autogiro that passes over your town, and, if 

 possible, study the motion of the horizontal blades. 



