156 THE INVISIBLE WORLD 



visited by a friend having a child the same age. 

 The cradle from the attic was occupied by the 

 child. From it the child took the diphtheria, and 

 died. 



The germs may be carried in clothing or on the 

 hands. The attending physician, if not disin- 

 fected, may so convey them from house to house. 



From the patient's room flies may carry the 

 germs to other rooms in the house, and to near 

 neighbors. 



Pet cats and dogs may carry the germs in their 

 fur, transfer them to other pet cats and dogs on the 

 street, and these last carry them home. This may 

 explain why not unfrequently a case of diphtheria 

 mysteriously occurs in a family where it would be 

 least expected. The pet cat or dog is responsible. 



The germs may be transferred in water. A city 

 or village takes its water from a certain stream. 

 Above the intake pipe on the stream is a case of 

 diphtheria. The germs find their way into the 

 stream and into the intake pipe. Among the users 

 of the water in the city or village an epidemic of 

 diphtheria is the result. 



The disease may be communicated in milk. 

 The dairyman washes his cans in water taken from 

 a brook contaminated with the germs. The milk 

 is contaminated. Among its consumers is created 

 an epidemic of diphtheria. 



Or cows drink the polluted water. The germs 

 live in their systems, appear in the milk, produce 

 the epidemic. 



