ANESTHETICS AND CO2 OUTPUT 



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tion is made. The results with formaldehyde, however, which 

 are explained further on, show that during exposure to this gas 

 the respiratory movements continue quite normally, but changes 

 in CO2 output are indicated. We, therefore, conclude that 

 cessation of respiratory movements cannot account for all these 

 changes in CO2 output. 



The relative toxicity of small and large doses of ether is of 

 some interest. Animals can be revived after being subjected 



Fig. 2 Curves showing effect of a small (reversible) dose of ether for one-half 

 and one hour on the CO2 production of grasshoppers. Ordinates represent grams 

 CO2 produced. Abscissa, body weights in grams. For further explanation see 

 text. 



to small doses for much over two to three hours, while with large 

 doses, as shown in figure 1 by the marked decrease in CO2 out- 

 put, the animal succumbs after a relatively short exposure. 



Some experiments carried out in the summer of 1919 on the 

 effects of ether on the CO2 output of grasshoppers, using the 

 barium-hydrate-titration method of Lund (10), are of interest in 

 showing that when the time intervals are long, one-half to one 

 hour, the changes in rate of CO2 output are generally not detected. 



Figure 2 gives the results of such experiments, and shows that 

 no marked differences in the total amount of CO2 given off occur 



