DUST AND ITS DANGERS. 65 



meat or milk. That the consumptive mother 

 may infect the nursing child with its food has 

 been abundantly proven. There are cases in 

 which the tubercle bacilli get into the blood 

 and are distributed to all parts of the body, 

 setting up such innumerable foci of disease 

 that the individual soon succumbs to the 

 violence of the poison. 



But after all, the prevailing seat of consump- 

 tion being in the lungs, the most natural 

 supposition is that the larger proportion of 

 consumptive people become infected through 

 the inhaled air. 



Now, as has been absolutely proven over 

 and over again, in almost all populous regions, 

 both out-of-doors and in-doors, tubercular per- 

 sons may be discharging thousands of living 

 tubercle bacilli every time they spit out mate- 

 rial from their lungs upon the streets, or upon 

 the floors, or wherever it can dry and mingle 

 with the dust. If not all the tubercle bacilli 

 are easily killed by drying, as has been proven, 

 have we not a sufficient explanation of the way 

 in which the infection of tuberculosis becomes 

 so widely and perpetually spread ? 



