FURNITURE, AND ITS USES. 235 



I speak now of adults, for children inhale 

 proportionally less about forty hogsheads in 

 twenty-four hours, or more than a gallon a 

 minute. 



It is proper to consider air which ,has been 

 once breathed, as unfit for further respiration, 

 or spoiled. But admitting this to be the case, 

 we spoil the air for the purposes of breathing, 

 at the rate of more than a gallon a minute. 

 So, in fact, Dr. Franklin used to say, fifty 

 years ago. 



VENTILATION. Now if these things are 

 so, how careful ought we to be, not to have 

 our rooms in which we sit or sleep too tight, 

 or too long closed ! What pains onght we to 

 take to ventilate (purify) them often, by open- 

 ing the doors or the windows ! This is the 

 more necessary where we are without fires ; 

 for a fire helps to ventilate a room, if there is a 

 chimney; though without the latter, it only 

 renders our condition the more dangerous, 

 since it increases more rapidly the poisonous 

 carbonic acid gas. You have probably read, 

 in the papers, the numerous stories of people 



