146 BACTERIA. 



Now, so long as they remain on the pavement they do no 

 harm. The sputum dries. But the bacilli are not killed by 

 drying. With other dry material from the pavement they 

 form part of the common dust. Any one of us may breathe 

 some of this kind of matter any day, for there are persons 

 afflicted with this dreaded disease in every community. Our 

 bodies furnish the very best soil for them to grow in. We do 

 not need to go into the street to be exposed. W T ho knows 

 what he brings into the house adhering to his clothing ? These 

 germs may be brought into the most cleanly houses in these 

 ways, or by the wind. 



Now, of course, all such material known to be highly dan- 

 gerous ought to be destroyed. If those suffering from such 

 diseases were careful to burn all such matter, most of the 

 seeds of this disease would be killed. Thus in time we 

 might stamp out the disease, as a scourge of Canada this- 

 tles. But so long as people expectorate upon the floors and 

 pavements, it will be difficult to prevent the spread of such 

 germ diseases. 



In hospitals such matters are now looked after with the 

 greatest care, and in private houses where there is intelligence 

 on these subjects. And it is encouraging to note the awaken- 

 ing of the public to the significance of the teachings of mod- 

 ern science on this subject, as shown by the fact that many 

 of the railroad and street-car companies now prohibit spitting 

 on the floors of cars, not merely because it is uncleanly, but on 

 the express ground that it is a means of spreading infectious 

 diseases. 



These disease germs are the smallest and simplest of liv- 

 ing things. They are plants ; and while all of them that are 

 well known have their scientific names, just as the larger 

 plants have, they are all included in one general group desig- 

 nated as Bacteria. 



