MICROBE OF THE BUBONIC PLAGUE 201 



cause is known. The means by which it is spread 

 are known. How to treat the disease is known. 

 How to prevent it is known. A vaccine has been 

 discovered. With it thousands in India are 

 inoculated. War is waged upon flies, mice, rats. 

 Mortality there is reduced eighty per cent. 



Recently, steamers from the old country brought 

 the plague to San Francisco. Landing at the 

 wharves, infected rats with their flees come ashore, 

 invade Chinatown. The plague breaks out. But 

 the authorities attack it right and left. They quar- 

 antine every patient. They vaccinate the exposed. 

 They raise an army of rat-killers, mice-killers, 

 ground squirrel-killers. For forty miles up and 

 down the coast, they make war upon the rodents. 

 They exterminate them. The plague is conquered. 



Ignorance is death Knowledge is life. 



