on air found in the pleura , &c. 5 1 5 
from the frontal sinus of 
4.5 carbonic acid gas, 
9.5 oxygene, 
86.0 azote. 
On the supposition that the air, previous to its entering 
these cavities, had undergone a partial change from respira- 
tion, the results described seem to indicate an absorption of 
oxygene. 
Other facts might be adduced, which, like the preceding, 
though not conclusive, tend to support the idea, that mucous 
membranes are capable of absorbing air. Of this kind, I 
conceive, are the results of the experiments of Messrs. Ma- 
gendie and Chevreul, on the composition of the air con- 
tained in the human stomach and intestines ;* and very 
recently, I have met with a fact, the bearing of which 
appears to be similar. In examining the body of a soldier, 
who had died of complicated disease, I found the head of the 
colon and the coecum exceedingly distended with air, and of 
a bright red colour, as if highly inflamed, whilst the ascend- 
ing colon w r as unusually contracted. The air collected under 
water amounted to 36 cubic inches, and consisted of 1 1 car- 
bonic acid gas, or air absorbable by lime-water, and of 89, 
chiefly azote, judging from its extinguishing flame, and not 
being itself inflammable. I regret I had not the means of 
ascertaining if any traces of carburetted hydrogene were 
present. 
The question, whether mucous membranes are capable of 
absorbing gases, I need not say is one of great importance 
in relation to the theory of respiration, and on that account 
* Ann. de Chira. et Phys. ii. 292. 
