34 GENERAL SCIENCE 



keep them out of our bodies. They are much more easily 

 killed if where we can get at them than when they 

 are in the body. Since many of the germs live best in 

 dark, moist places, sunshine is the best natural germ 

 destroyer or disinfectant that man can use. Let the 

 sunshine into the rooms of all buildings. The faded 

 paper on the wall will not cost as much as sickness 

 and moderately poor health. Hang clothing, carpets, 

 and bedclothes in the sunshine and air. The wind and 

 sunshine work together killing germs. 



(A) Germs and Heat. Germs cannot stand a very 

 high temperature. Boiling water will kill most germs in 

 a short time. For this reason the bedding and clothing of 

 a person who has a germ disease such as diphtheria, 

 typhoid fever, measles, tuberculosis, etc. should be 

 washed in boiling water and hung to dry in the wind and 

 sunlight. The germs in milk can be killed by boiling it or 

 by pasteurizing it. To pasteurize milk, heat it to from 

 140 to 150 F. for about thirty minutes, then place it 

 in closed vessels to prevent other germs from entering. 

 Many of the diseases of children can be avoided by using 

 pasteurized milk. 



Dishes used by diseased persons can be made harmless 

 by leaving them in almost boiling water for a few minutes. 

 Foods that are well cooked or baked are thoroughly steri- 

 lized. But germs may get into such foods after they are 

 cold, by being handled and hauled through the streets for 

 delivery, as is done with bread and other baked articles. 

 The receptacles for canned goods should be placed in 

 the sunshine for several days and washed in boiling 

 water just before using. Boiling the food for canning 

 usually kills all bacteria, yeast, and mold that may be 

 .in it. If it is placed in the jars while hot and then 



