to wash away bacteria. Both the lymph and the strong 

 salt solution are unfavorable to the growth of bacteria. So 

 far as the white corpuscles are concerned, strong saline solu- 

 tions are unfavorable to their vitality; but when the wound 

 has become healthier, it is usual to decrease the strength of 

 the salt solution until its saturation has reached that of a 

 fluid of the same specific gravity as the blood. In a fluid 

 of this degree of concentration the body cells can live and 

 act freely. 



TUBERCULOSIS 



Tuberculosis, a disease which causes about one-third of 



Thf» C t a ^ ^ e deaths which occur between the 



—~ . p- ages of 18 and 45, and kills each year about 



le ague 15Q0Q0 people in the United states, is 



caused by a bacterium which may grow in a great many 

 different parts of the body, although it is most likely to be 

 found in the lungs, causing tuberculosis of the lungs, or 

 consumption. The germ does not grow all through the 

 lungs in this disease, but here and there at special points, 

 where there form hard little knots or tubercles, from which 

 the disease is named. 



Tuberculosis of the bones is not uncommon among children, 

 and a great many of the lame people we see on the streets 

 are crippled from this cause. 



The primary cause of tuberculosis is a germ discharged in 

 T - r f the spray and sputum coughed out by con- 



T , 1 . sumptives, and infection comes in most 

 cases from getting these human discharges 

 into the mouth. Sometimes the germ is inhaled in dust, 

 but it is more frequently transferred from one person to 

 another by rather direct contact. 



A great many cattle suffer from tuberculosis, and children 

 may become infected by drinking the milk of tuberculous 

 cows. 



42 



