THE HUMAN EYE 287 



sickly appearance, and his blood loses much of its ability 

 to destroy the tiny one-celled organisms which exist there 

 in countless numbers. By working in the open air and 

 sunshine the body is kept in good physical condition 

 and is then able to resist the attacks of most foreign 

 one-celled organisms. Bacteria, one-celled organisms, live 

 mostly in dark, damp places and are not accustomed to 

 much light. When they are exposed to sunlight, they die. 

 For this reason living-rooms should be well lighted and 

 as much of the direct sunlight should be permitted to 

 enter the rooms as possible. The injury to the paper on 

 the walls and to the carpet is not so expensive as ill- 

 health. Faded paper does not produce the discomfort 

 that lost health does. Paper and carpets that do not 

 fade perceptibly in the presence of sunlight should be 

 selected. 



Hospitals are now built so that most of the rooms 

 receive the direct rays of the sun during part of the day. 

 Patients are often required to sit in the sun and open 

 air. The sleeping quarters of tuberculosis sanatoriums 

 are built with three open sides so that abundant light 

 and air can enter. The recreation sheds are built with 

 the south side entirely open so that the sun can shine 

 into them. Sunlight and fresh air are the two great pre- 

 ventives of disease, and they will help to cure many 

 diseases. 



Artificial lights unfortunately do not kill many germs. 

 Public buildings and offices where artificial lights must 

 be used all the time are not the most healthful places 

 in which to work. Such rooms and offices should be fre- 

 quently disinfected. Many modern church buildings have 

 such dark colors in the "memorial and picturesque" 

 windows that scarcely a ray of sunlight can ever enter 



