DUST AND ITS DANGERS. 



lows, it is by no means true that they always 

 are or ever need to be. The breath itself, the 



FIG. 6. LYMPH FILTERS (LYMPH-GLANDS) AT THE ROOT OF THE 

 LUNG, THE SEAT OF LOCAL AND HEALED TUBERCULOSIS. 



Two of the lymph filters at the root of the lung which have 

 become blackened from inhaled dust. But in addition to this, one 

 of them the larger shows two white spots which are caused by 

 the lodgment here of the tubercle bacilli. These germs, caught in 

 the meshes of the filter and thus kept out of the blood, have grown 

 here for a time. But owing to their growth or their presence, the tissues 

 about them have been so stimulated or irritated, that a dense organ- 

 ized wall has been formed around the germs, completely shutting them 

 off from the rest of the body. This is the way in which the cure of 

 consumption is sometimes effected. Nowhere else in the body of this 

 person, who died from an acute disease, were there any evidences 

 whatsoever of tuberculosis, 



