1909.] Presence of Carbon Monoxide in Normal Blood, etc. 527 



which the blood gases before analysis were freed from chloroform by shaking 

 with a few cubic centimetres of alcohol in the laboratory tube of the gas 

 analysis apparatus, and, finally, from traces of alcohol vapour by shaking 

 with ice-water. We quote one experiment : — 



Weight 

 of cat. 



Duration 

 of 



anaesthesia. 



Volume 



of 

 blood. 



Temp. 



Duration of oxygen 

 current in 



Iodine liberated in 

 terms of N/1000 

 sodium thiosulphate 

 in 







Control. 



Experi- 

 ment. 



Control. 



Experi- 

 ment. 



kilos. 

 3 



hour. 



1 



c.c. 

 54 



o 



151 



min. 

 135 



min. 

 135 



c.c. 

 1-7 



c.c. 

 2 



The gas, therefore, liberated iodine equivalent only to - 3 c.c. N/1000 

 thiosulphate, a quantity which may very well be ascribed either to the 

 incomplete elimination of the chloroform or to the variation of the control 

 value of the tube. 



[October 12, 1909. — "Finally, in order to settle the question quite 

 conclusively, we made the following experiment: — 



A cat weighing 3 - 6 kilos, was anaesthetised by means of carefully purified 

 •chloroform for 1 hour 15 minutes ; 108 c.c. of blood were withdrawn 

 in two lots of 54 c.c. from the carotid artery. The gases were completely 

 pumped out of this blood at 40° C, and divided into two portions. The one 

 half was slowly bubbled through 1 : 100 blood solution, and examined 

 ■by Haldane's method in the manner described in the earlier part of this paper. 

 No trace of carboxyhaamoglobin could be detected. 



The other half of the blood gas was allowed to stand for 45 minutes in 

 ;the laboratory tubes of the gas analysis apparatus in the presence of a few 

 lumps of moistened potash. It was then transferred -to the measuring tube, 

 and thence bubbled through 1 : 100 blood solution as before. The presence 

 of carboxyhsemoglobin was obvious in this without dilution. 



The results were confirmed spectroscopically in both samples before and 

 after the addition of reducing agents."] 



Conclusions. 



1. Our experiments lend no support to the view that carbon monoxide is a 

 normal constituent of the blood gases. We think that the small quantities of 

 iodine found in Desgrez and Nicloux' experiments are due to the decomposition 

 of iodine pentoxide at the temperature (150° C.) of their experiments. 



