126 1'HYSIOLOGY. 



on the floor, but better a thousand times there than in our 

 lungs. 



Lung Diseases. Statistics seem to show that one 

 seventh of the deaths among the civilized races is due to 

 lung diseases. The best authorities are now agreed that 

 consumption is not hereditary. But it appears that there 

 may be inherited a tendency to this disease, so that, if ex- 

 posed, such persons are more likely to contract the disease 

 than those not so predisposed. 



Probably anything that lowers the general vitality makes 

 the system more ready to succumb to any of these con- 

 tagious diseases. We have all noticed what a difference 

 there is among individuals in the readiness with which they 

 " catch " contagious diseases. 



Destruction of Germs by Colorless Corpuscles. It is 



believed by some physiologists that the colorless blood 

 corpuscles may take these germs of disease into their sub- 

 stance, and destroy or change them so that the disease is 

 warded off. In other words, they may be compared to a 

 cat that catches and eats the mice which invade a house. 



How to ward off Contagious Diseases. A good gen- 

 eral condition of the body helps greatly to ward off dis- 

 eases of this nature. A cheerful condition of mind and 

 body should be cultivated. In times of widespread con- 

 tagious disease, if one is terrified into the belief that he is 

 going to have the disease, he is more likely to take it. 



Thorough cleanliness, plenty of direct sunshine, care in 

 diet, and the keeping of the body in good tone, all these 

 reduce the chances of "taking" contagious diseases. 



An open-air life, abundant nutritious food, and freedom 

 from anxiety are probably the best restoratives for incipient 

 consumption. 



