Obfervations on inflammable Air. 34.Q 
ferved, that it fuffered no diminution^ exactly as it fuf- 
fered none before it had been put into the bladder. 
Having afcertained, in this manner, that the bladders 
do not in any manner contribute to render the inflamma- 
ble air extracted from metals better in its nature, there re- 
mained no other way of afcertaining Mr. sheele’s expe- 
riments, and of underftanding why I had been able to 
breathe it eleven times, than by fuppofing that the air of 
the lungs, which can never be thoroughly emptied by be- 
ing mixed with the inflammable air, alters it, See. It is 
well known, that in an ordinary expiration about thirty- 
five cubic inches of air are expelled from the lungs. In a 
very violent expiration, following a natural infpiration, 
the air expelled may amount to fixty cubic inches. Thefe 
forty inches of pulmonary air are mixed with the in- 
flammable air, and are expelled from the lungs in pro- 
portion to the remaining air that is breathed after that 
the lungs have been thoroughly emptied. In the expe- 
ment above related, of the three infpirations I made into 
the inflammable air, it may be eafily fuppofed, that twenty 
inches or more of pulmonary air were joined with the in- 
flammable air, and entered into the bladder. This pulmo- 
nary air, although it is itfelf partly phlogifticated, is how- 
ever diminifhed by nitrous air; and when it ftands in 
the bladder it is nearly equal to — th of the inflammable 
Vox,. LXIX. A a a 
air 
