326 



JOSEPH HALL BODINE 



Figure 1 shows the effect of a smaU and a large dose of ether on 

 the CO2 output. In both cases an increase in CO2 output took 

 place, which was followed by a decrease. With a small or rever- 

 sible dose this decrease remains practically constant during the 

 experiment ; with a large dose (irreversible) the decrease continues 

 up to the end of the experiment. It might be thought that this 

 increase in both cases was due to movements of the animal 



200 



3£i 



Fig. 1 Curves showing the effect of 0.5 cc. ether (curve A), 1 cc. ether (curve 

 C), and 2 drops — 0.08 cc. — ether (curve B) on the CO2 production of grasshoppers. 

 The point marked on the abscissa indicates the beginning of exposure to ether 

 for curves A, B, and C; previous to this the normal production of CO2 was deter- 

 mined. The normal rate (which is taken as 100 per cent) corresponds to the 

 production of a definite amount of CO2 in 25.2 minutes for curve A, in 7.7 minutes 

 for curve B, and in 8.5 minutes for curve C. Curves A and C irreversible, curve 

 B reversible. For further explanation see text. 



caused by the anesthetic. As a matter of fact, however, when 

 an animal is exposed to the ether for a brief period (one to two 

 minutes) prior to the recording of the CO2 output and all respira- 

 tory movements have ceased, the same increase is noted. With 

 a small dose the respiratory movements continue quite normally 

 for approximately fifteen minutes, when the}^ gradually become 

 greatly retarded and eventually cease; with a large dose, the 

 respiratory movements stop in a few seconds. An animal ex- 

 posed to a large dose for one-half minute prior to recording the 

 CO2 output ceases to breathe many seconds before the determina- 



