1909.] Presence of Carbon Monoxide in Normal Blood, etc. 521 



comparisons made with Michael's tintometer. Differences could, however, be 

 readily detected when 0"2 c.c. of blood of similar dilution 1 : 100 saturated 

 with CO gas was added to either of the original solutions through which the 

 blood gases or artificial mixture had been bubbled. 



Duration of Volume of 



anaesthesia. blood, 



hrs. c.c. 



III. 2 54 



20 min. later. 27 



Gases bubbled through as before, examination as above. Xo difference 

 whatever could be detected. 



Duration of Volume of 



antesthesia. blood, 



h. m. c.c. 



IV. 1 30 54 

 30 min. later. 54 



The total gases as before bubbled through 1 : 100 human defibrinated 

 blood. On examination as before, no differences whatever could be detected. 



These experiments, we submit, conclusively show that when the blood of 

 ansesthetised animals is evacuated at 40° C. until no further gas is evolved, 

 the gas obtained contains no recognisable trace of carbon monoxide, and, 

 therefore, if this is present it is present in far smaller quantities than Desgrez 

 and Nicloux state to be the case in normal blood gases. Therefore, chloroform 

 is not decomposed in the organism or in the blood with production of carbon 

 monoxide. If there was any carbon monoxide really present in their experi- 

 ments, this must have been due either to the acid which they added before 

 evacuation of the gases, a view from which they explicitly dissent, or have 

 been produced in their experiments. 



It now became necessary to arrive at some explanation for the iodine 

 evolved in the experiments of Desgrez and Mcloux, and the most obvious 

 line of research was to study the effect of chloroform vapour on iodic 

 anhydride at various temperatures, and also the effect of heat alone on this 

 substance. For this purpose the following apparatus was employed. The 

 gases of the blood, mixtures of air and chloroform or other gases under 

 investigation were swept over the iodine pentoxide by a current of oxygen 

 aspirated at a rate varying from 1 to 2 litres an hour. This plan was 

 adopted to obviate the entrance of air of the laboratory, which might 

 contain traces of carbon monoxide ; and as a further precaution the oxygen 

 was passed through a long combustion tube filled with red hot copper oxide. 



