ON THE ANIMAL FRAME. 295 



and Pepys found the air remaining in the lungs 

 of a man after death somewhat exceeded 100 

 cubic inches. I found formerly that after a full 

 inspiration I could blow out 200 cubic inches 

 of air from my lungs, but was then quite e>g^ 

 hausted. My ordinary inspirations and expira- 

 tions amounted each to about 30 cubic inches.* 



Judging from the above facts and considerations 

 I should be disposed to conclude that the medium 

 vohime of air in the lungs of a middle sized 

 person would not be less, but rather more than 

 100 cubic inches. Besides the lungs there are 

 no other receptacles for air, I believe, in the 

 body except the stomach and bowels, which are 

 occasionally more or less inflated with portions 

 of air either from the atmosphere or from other 

 sources. If we allow 160 cubic inches for the 

 volume of air, contained in the whole man when 

 entirely immersed in water, it will be as fair an 

 estimate perhaps as can be made. But it may 

 be imagined by some that the whole substance 

 of the body is pervious to air ; that the skin, the 

 flesh, the blood and even the bones, may be 

 imbued with air, somewhat in the same manner 

 that water is, and yet have no cavities or cells in 

 which the air is collected into a visible volume. 

 Whether such an idea has ever been entertained 



• Memoirs, toI. II. (new scries, p. 26.) 



