THE ATMOSPHERE 



cates a person and makes him feel as if he should 

 certainly die it' it kept on a little longer. " 



"\Vell, I hope you are convinced of the necessity 

 of air in order to live. All animals, from the tiniest 

 mite, hardly visible, to the giants of creation, are 

 in the same condition as you: on air, first of all, 

 their life depends. Even those that live in the 

 water, n'sh and others, are no exception to this rule. 

 They can live only in water into which air infiltrates 

 and dissolves. When you are older you shall see a 

 striking experiment which proves how indispensable 

 to life is the presence of air. You put a bird un- 

 der a glass dome, shut tight everywhere; then with 

 a kind of pump the air is drawn out. As it is with- 

 drawn from the inside of the glass cage, the bird 

 staggers, struggles a moment in an anguish horrible 

 to see, and falls dead." 



"It must take a lot of air," was Emile's com- 

 ment, "to supply the needs of all the people and 

 animals in the world. There are so many!" 



"Yes, indeed; a great quantity is needed. One 

 man needs nearly 6000 liters of air an hour. But 

 the atmosphere is so vast that there is plenty of 

 air for all. 1 will try to make you understand it. 



"Air is one of the most subtle of substances; a 

 liter of it weighs only one gram and three decigrams. 

 That i> eery little: the same volume of water weighs 

 lot in Drains; that is to say, 769 times as much. 

 llo\vever, such is the enormous extent of the atmos- 

 re that the w'mht of all the air composing it out- 

 >trips your utmost power- of imagination. If it 



