Anatyfis of the Air. 239 
fame time I could plainly perceive that my 
lungs were much fallen, juft in the fame 
manner as when we breathe out of them 
all the air we can at once. Whence it is 
plain that a confiderable quantity of the 
elafticity of the air contained in my lungs, 
and itl the bladder, was deftroyed 5 which 
fuppofing it to be 20 cubick inches, it will 
be part of the whole air, which I breath* 
ed to and fro ; for the bladder contained 
74 cubick inches, and the lungs, by the 
following Experiment, about 1 66 cubick 
inches, in all 240. 
Thefe effeds of refpiration on the ela- 
fticity of the air, put me upon making an 
attempt to meafure the inward furface of 
the lungs, which by a wonderful artifice 
are admirably contrived by the Divine Ar- 
tificer, fo as to make their inward furface 
to be commenfurate to an expanfe of air 
many times greater than the animal's body; 
as will appear from the following eftimate, 
viz. 
Experiment CIX. 
I took the lungs of a Calf and cut off 
the heart and wind-pipe an inch above its 
branching into the lungs; I got nearly the 
fpecifick 
