76 



LIVING IN AN OCEAN OF AIR 



bottle. A hole is punched through the can 

 near the bottom to allow air to enter the 

 fountain. Water may run out. The higher 

 the reservoir is placed above F, the greater 

 the force in the fountain. 



4. EXPLORING IN THE UPPER ATMOSPHERE 

 Read up on this topic in books and 



periodicals. Find out what people have 

 explored the atmosphere higher than the 

 highest point of land and how they have 

 done it. What do they expect to achieve by 

 these adventures? What are the dangers? 

 Have different members of the science club 

 report upon different achievements. 



5. How TO SHOW THE CRUSHING POWER OF 

 THE ATMOSPHERE 



Use an empty gallon oil or sirup can which 

 has a small opening that can easily be closed 

 air tight with a cork. Put about one half inch 

 of water in it. Place it over a fire, and boil 

 the water. When the steam has driven out 

 all the air (two minutes of boiling), shut off 

 the gas and put the stopper in air tight. Place 

 the can in the sink and pour cold water upon 

 it. Do you understand the reasons for the re- 

 sult? How many square inches of surf ace has the can ? What is the 

 pressure of the atmosphere on 1 sq. in.? On the total surface? 



6. How TO SHOW THE CHANGES THAT TAKE PLACE IN THE CHEST 



CAVITY WHEN WE BREATHE 



Have some member of the club make a large chart of the diagram 

 shown on this page and 

 a large model of the me- 

 chanical device shown 

 on the opposite page. 

 Have the club members 

 study the chart carefully 

 and then have the dem- 

 onstrator work the model 

 while asking the follow- 

 ing questions : 



(1) What happens to 

 the human diaphragm 

 when the ribs are raised ? 







