FURNITURE, AND ITS USES. 227 



nose, but without some other machinery, it 

 would go no farther than the throat, before it 

 must return or pass out at the mouth. A 

 little, it is true, is swallowed, both in our food 

 and drink ; but the quantity is not very con- 

 siderable. 



There is air, moreover, in every part of the 

 body ; if there were not, we should soon be 

 crushed. The atmosphere in which we live 

 presses on us with a tremendous force, equal, 

 it is said, in a middling sized man, to about 

 32,000 pounds. But as there is air in us, in 

 all our solids and fluids, which presses outward 

 while the atmosphere presses in the other 

 direction, we do not perceive it. 



But when 1 said the blood must be purified 

 by the air, I meant in a manner much more 

 rapid and effectual than could be done by its 

 gradual introduction, and its circulation in the 

 vessels. 



THE LUNGS. The house I live in contains 

 something like a great bellows, by whose curi- 

 ous operation the blood is cleansed and purified* 

 It is contained in the upper story, and fills 



