HYGIENE OF RESPIRATION 171 



closed except in warm weather. If, during the meeting, 

 the room becomes too warm (not if it becomes foul with 

 impure air), some one will open one or more windows to 

 their full height ; the strong draught soon cools the room 

 and chills some one, whereupon he goes to the window 

 and shuts it tight. One absurd extreme thus follows 

 another. All that was necessary, if there was no scien- 

 tific provision for ventilation, was for all of the windows 

 to have been opened, for an inch or less, when the as- 

 sembly began, and allowed to remain so ; then no one 

 would have been too hot or too cold, or would have 

 suffered from foul air. 



287. What is the probable cause of persons fainting 

 or going to sleep in church ? With the foul air was 

 combined what other disadvantage to breathing, as shown 

 by one of the measures often taken to restore a person in 

 a faint, especially if a woman ? 



288. The ventilation of the schoolroom is often deplor- 

 able. A visitor, upon entering a schoolroom, especially 

 if the school has been in session for an hour or more, 

 may notice a stifling, foul-smelling atmosphere. The chil- 

 dren have rushed in from their active games with their 

 clothing saturated with perspiration. Their healthy skins 

 perspire more freely than do those of adults. Some of 

 them may have coughs or colds, and sometimes come 

 from sick rooms. 



289. Carbon monoxid forms in the stove if the draught 

 is closed too much, and escapes through cracks and seams 

 in the stove, and, if the stove is red-hot, through the iron 

 itself. Carbon monoxid is different from the dioxid in 

 being imperfectly oxidized, and its attraction for oxygen 

 causes it, when breathed, to attack the red corpuscles of 

 the blood causing headache and dizziness, for the mon- 

 oxid is an active poison, not merely negative like the 

 dioxid. The ashes from the stove, the dust from the 



