undergoes in the act of coagulation. i 8i 
not allow Mr. Bauer to rest, till he gave me his assistance in 
instituting experiments, to ascertain whether any thing simi- 
lar takes place in animal bodies. 
The first object of our enquiry was to know, whether any 
gas is to be found in the blood while circulating in the vessels, 
and under what circumstances it is separated from it. That 
the blood, whilst circulating in the arteries and veins, holds 
a considerable quantity of gas in solution, is proved by the fol- 
lowing experiments, made at my request, by Professor 
Rrande. Blood was drawn from a vein in the arm, and 
whilst yet warm was placed under the receiver of an air pump; 
during the exhaustion of the receiver, there was a considera- 
ble escape of gas from the blood, so that it had the appearance 
of effervescing, and soon depressed the quicksilver in the 
gage of the pump. He afterwards ascertained that this gas 
is carbonic acid gas, is met with in the same proportions in 
arterial and venal blood, and two cubic inches were extricated 
from every ounce of blood.* 
That a considerable portion of this carbonic acid gas, is 
extricated from the blood during the spontaneous coagulation 
of that fluid, was previously proved by Mr, Bauer, who filled 
glass tubes with blood recently drawn, and tying them over 
with bladder, inverted them. At first there was no appear- 
ance of gas upon the surface, but as the blood coagulated, it 
was separated, and in the course of 24 hours was found in 
considerable quantity. 
Having ascertained not only the existence of gas in the blood, 
but that it is separated during the process of coagulation, I was 
most anxious to discover whether, as in vegetables, the gas, 
* See Annales de Chimie, Tom. XIII. 
