430 SANITATION 



and our faces. We should make every effort, by the use 

 of good screens, to keep flies out of our houses, and away 

 from our food. Especially should we protect little chil- 

 dren from them. 



But while the slogan "Swat the fly!" rings through the 

 land, we must remember that the adult fly is largely what 

 we make it. It does not travel far. The germs that it 

 carries it gets from the neighborhood where it lives, and 

 where we live. To make a campaign against the fly 

 effective, we need to keep our neighborhood clean and 

 sanitary. Flies will not breed if there are no dirty places, 

 such as manure heaps and heaps of kitchen waste, in which 

 the adult fly can lay its eggs. Flies will not carry germs 

 from house to house if every house is properly' screened, 

 and if we take care to destroy the disease germs that 

 come from sickness. Flies will not find food, out of doors, 

 if crumbs and dish water are not thrown into the yard, 

 and if garbage is carefully covered, removed, and de- 

 stroyed. So, to get rid of the fly and the long train of 

 troubles for which it is responsible we need not only to kill 

 it when we find it, but we must keep our neighborhood clean. 

 If we do this, the fly cannot develop and multiply there. 



What is true of the fly is largely true of the mosquito. 

 Its breeding habits are well known (cf. 339, Fig. 264) ; 

 the eggs must be laid in water. In inserting its sharp 

 proboscis into the skin of a sick person, it becomes in- 

 fected, and then introduces the infection into the body of a 

 person who is well. The region about Rome has long 

 been filled with deadly malaria, but we now know that 

 people may live there without fear, if they are screened 

 against malaria mosquitoes. 



