136 The Story of the Bacteria 



characterized by an eruption on the skin. 

 The old Greeks knew them and called it a 

 "flowering out," and so we call the lot "the 

 exanthemata." We do not know what incites 

 them. The search for bacteria has thus far 

 failed. 



It has been conjectured that minute ani- 

 mals protozoa may be to blame. Some 

 morning we shall probably learn in the papers 

 that a tired-eyed worker in the laboratory 

 has found the clue, and we shall wonder that 

 we did n't always know it. 



But though we do not yet know what in- 

 cites them, we have for .one smallpox so 

 efficient a preventive in vaccination, that it 

 has largely lost its terrors in civilized and 

 intelligent communities, and has ceased to 

 figure largely in health statistics. This 

 happy state has been secured through the 

 wisdom and vigilance of health authorities, 

 which must be ceaselessly maintained. 



Hydrophobia or Rabies 



Here is another infectious disease usually 

 acquired through animals, in this country, 



