196 Cc. J. MARTIN. 
by means of a water bath. The gases were analysed by Bunsen's 
method, and the quantities found, reduced to their volumes ata 
temperature of 0° C., and 760 mm. of mercury pressure. In the 
tables of experiments the amounts of gas are expressed in volumes 4 
per hundred volumes of blood. i 
The determination of the partial pressure of CO, in normal 
blood was not undertaken. The exhaustions, and analyses required 4 
to ascertain the absolute amount of gases in two samples of blood, 
and of the tension in the poisoned blood, together with the other 
details of the experiment, occupied the entire day, and did not 
allow time for any further aérotonometric observations. 5 
The averages of the results arrived at by Strasburg! and 
Nussbaum? for the tensions of CO, in arterial and venous blood 
for the dog are—2-°8% and 4:5/ of an atmosphere respectively, 
and I have used these numbers for purposes of comparison. . 
In determining the tension of the gases in the blood of dogs 
poisoned by venom, I have taken advantage of the fact that the 
coagulability of the blood is under these circumstances sc 
greatly diminished or altogether in abeyance. The method be 
modification of that used by Léon Fredericq’® to ascertain 
tension of the gases in peptone blood. 
The apparatus consists of two glass tubes 4 and B of about 
1 c.m. internal diameter and 25 cc.m. capacity. These tw? abe 
~ 
are surrounded by a larger tube through which a current of 
at 40° C. is kept circulating. At both ends the tubes 
are attached by india rubber{tubing ‘to Y shaped glass 
296. 
1 Pluger’s Arch.,” Ba. vr., 8.65. 2 Ibid., Bd. vit ® 
3 “Centrbl. f. Physiol.,” vir., N. 2. 
