LUNGS, DUST, AND TOBACCO SMOKE 145 



Our lungs are not only like the branches of a tree 

 but they are like two big bottles with one small mouth. 

 When the cork is in a bottle the water cannot evaporate 

 fast. It is so with the lungs: when the mouth is shut 

 the tubes do not dry very quickly, and for the sake 

 of the cilia they need to be damp. 



That is one of the good reasons for not smoking 

 tobacco. When a man sends warm, dry tobacco smoke 

 into his lungs, as some people do, he does three harmful 

 things to his breathing machine. 



1. He keeps the cilia too dry. 



2. He sends such a cloud of smoke against 

 the cilia that a great deal of it manages to 

 get into the lungs. 



3. There is a poison in the tobacco that a 

 man smokes, and when the smoke gets into 

 the lungs, of course the poison gets there 

 too. The cilia cannot send it out. 



The lungs are so important and so delicate, and the 

 cilia are such good friends of ours, that we should help 

 them in every way. 



QUESTIONS 



1. What does exercise do to breathing? 



2. What good does deep breathing do to the lungs? 



3. What kind of air should be used? 



4. What are cilia like? 



