^ 5 ^ Analyjis of the Ah\ 
this deciudcd from the above found cavity i 
of the lungs, there remains loo cubick inches 
for the fum of the cavity of the veficles. ' 
Upon viewing fome of thefe veficles with 
a microfcope, a middle fized one feems to 
be about tIo part of an inch diameter 5 then i 
the fum of the furfaces in a cubick inch I 
of thefe fmall veficles (fuppofing them to be 
lb many little cubes, for they arc not fphe- 
rical) will be 500 fquare inches ; which mul- 
tiplied by the fum of the cavity of all the : 
veficles in the lungs, 100 cubick inches, 
will produce 30000 fquare inches 5 one : 
third of which muft be dcduded, to make 
an allowance for the abfencc of two fides i 
in each little veficular cube, diat there 
mi2;ht be a free communication amons 
them for the Air to pafs to and fro ; fo 
there remains 200C0 fquare inches for the 
fum of the furfacc of all the veficles. 
And the Bronchia containing 41 cubick 
inches, fuppofing them at a medium to 
be cylinders of tV of an inch diameter, their 
lurface will be 1635 fquare inches, which 
added to the furface of the veficles makes . 
the fum of the furface of the whole 
lungs to be 21635 fquare inches, or :• 
150 
