96 THE VITAL PROCESSES 



The air should, if possible, be warmed before reaching the 

 occupants. 



3. If the wind is blowing, ventilate principally on the 

 sheltered side of the house. 



Ample provision should be made for fresh air in sleep- 

 ing rooms, and here again drafts must be avoided. Espe- 

 t cially should the bed be so placed that strong air currents 

 do not pass over the sleeper. In schoolhouses and halls 

 for public gatherings the means for efficient ventilation 

 should, if possible, be provided in the general plan of 

 construction and method of heating. 



FIG. 47. Artificial respiration as a laboratory experiment. Expiration. 

 Prone-posture method of Schaffer. 



Artificial Respiration. When natural breathing is temporarily sus- 

 pended, as in partial drowning, or when one has been overcome by 

 breathing some poisonous gas, the saving of life often depends upon 

 the prompt application of artificial respiration. This is accomplished 

 by alternately compressing and enlarging the thorax by means of vari- 

 able pressure on the outside, imitating the natural process as nearly as 

 possible. Following is the method proposed by Professor E. A. 

 Schaffer of England, and called by him " the prone-posture method 

 of artificial respiration " : 



also arise from the skin, teeth, and clothing which, if not dangerous to the health, 

 are offensive to the nostrils. If on going into a room such odors are detected, the 

 ventilation is not sufficient. This is said to be a reliable test. 



