DANGERS OF VITIATED AIR 257 



way to breathe is to have both the chest and the abdomen 

 partly inflated when each breath is taken. 



References : 



1. 1407 : 110-112. Respiration in Plants. 



2. 1501:192-204. The Lungs. 



3. 1503:380-390. Respiration. 



a. 1404 : 194-195. The Breathing of Plants. 



6. 1505 : 72-88. Respiration and Ventilation. 



c. 1506 : 138-149. The Lungs and Breathing. 



d. 1507 : 190-210. The Mechanism and Chemistry of Res- 



piration. 



e. 1509 : 165-178. Respiration. 

 /. 1510 : 23-44. Respiration. 



'g. 1511 : 107-121. The Respiratory Organs. 



190. DANGERS OF VITIATED Am 



The air of an insufficiently ventilated room contains, after 

 occupancy, a considerable, quantity of carbon dioxide, par- 

 ticles of animal tissue which have been expelled from the lungs, 

 disease germs, and unpleasant if not dangerous odors from 

 perspiration. The odor of the air in a room is a good index of 

 its impurity, although the odor, in itself, may be harmless. 

 A test for the amount of carbon dioxide present likewise indi- 

 cates the degree of vitiation, six parts in ten thousand being 

 as much as can be safely endured, although this amount of 

 carbon dioxide alone is harmless. 



Vitiated air tends to produce a poor appetite, weakens the 

 constitution, and may lead to consumption. The effects of 

 bad air are slow in their results and too often are not recog- 

 nized as due to lack of sufficient ventilation. Many a vaca- 

 tion trip owes all its beneficial results to the fact that fresh 

 air was unlimited. Consumption is being cured by plenty of 



