295 
* 

three cubic inches ; so that, of the 13.1 inches of air 
originally employed, three had disappeared, and TT-T 
- 7 .yT or a portion of the air was thus converted 
into carbonic acid, which comes very near to the 
proportion of oxygen gas which the atmosphere is 
known to contain. Hence we infer, that, in this 
experiment, all the oxygen gas that disappeared was 
converted into carbonic acid ; and, consequently, we 
deny that any oxygen penetrated the bladde^ in or- 
der to combine with the blood. 
587. As thus it is denied that the blood, in these 
experiments, received any ponderable matter from 
the air, so likewise it will appear, from the facts 
which follow, that the air receives no such matter 
from the blood. We filled bladders with water, and 
suspended them in jars of atmospheric air, in the 
manner described above ; and found that the oxy- 
gen gas of this air was converted into carbonic 
acid, in the same manner as when the bladders were 
filled with blood ; and if the experiment was conti- 
nued a sufficient length of time, the whole of the 
oxygen gas was, in like manner, made to disappear. 
The same effects followed from the introduction of 
moistened empty bladders ; and, indeed, it is the usual 
effect produced in the air by every moistened ani- 
mal substance. If, therefore, the moistened bladder 
be thus capable, by itself, of acting on the air, we 
are entitled to conclude that it exerts the same ac- 
tion when it is filled with blood ; and as, on this 
supposition, the oxygen gas will unite with the car- 
bon, furnished directly by the bladder, we have no 
ground whatever to suppose this carbon to come from 
