376 MAN'S IMPROVEMENT OF HIS ENVIRONMENT 



fresh air, but warms over the stale air in a room. Steam causes 

 our rooms to be too warm part of the time, and not warm enough 

 part of the time. Thus we become overheated and then take cold 

 by becoming chilled. Steam heat is thus responsible for much 

 sickness. 



Lighting. - - Lighting our rooms is a matter of much importance. 

 A student lamp, or shaded incandescent light, should be used for 

 reading. Shades must be provided so that the eyes* are protected 

 from direct light. Gas is a dangerous servant, because it contains 

 a very poisonous substance, carbon monoxide. "It is estimated 

 that 14 per cent of the total product of the gas plant leaks into the 

 streets and houses of the cities supplied." This forms an unseen 

 menace to the health in cities. Gas pipes, and especially gas cocks, 

 should be watched carefully for escaping gas. Rubber tubing 

 should not be used to conduct gas to movable gas lamps, because 

 it becomes worn and allows gas to escape. 



Insects and Foods. - - In the summer our houses should be pro- 

 vided with screens. All food should be carefully protected from 



During the summer all food should be protected from flies. Why ? 



flies. Dirty dishes, scraps of food, and such garbage should be 

 quickly cleaned up and disposed of after a meal. Insect powder 

 (pyrethrum) will help keep out 'croton bugs" and other undesir- 

 able household pests, but cleanliness will do far more. Most 

 kitchen pests, as the roach, simply stay with us because they find 

 dirt and food abundant. 



