ANESTHETICS AND CO2 OUTPUT 



329 



alone, i.e., a decrease followed by an increase and this followed 

 by a decrease which is irreversible. 



Acetone. The effects of acetone are quite different from those 

 of either chloroform or ether. Small doses (2 to 4 drops) cause 

 cessation of respiratory movements in ten to fifteen minutes. 

 The respiratory movements, however, during this time become 



Fig. 4 Curves showing the effect of 2 drops — 0.08 cc— acetone (curve A), 

 4 drops — 0.16 cc. — acetone (curve B), and 2 drops — 0.08 cc. — xylol on the CO2 

 production of grasshoppers. The point marked on the abscissa indicates 

 the beginning of expo.sure to reagents for curves A, B, and C; previous to this 

 the normal production of CO2 was determined. The normal rate (which is taken 

 as 100 per cent) corresponds to the production of a definite amount of CO2 in 10.5 

 minutes for curve A, in 15.5 minutes for curve B, and in 9.7 minutes for curve C. 

 Curves A, B, and C irreversible. For further explanation see text. 



successively slower, until toward the end they are scarcely per- 

 ceptible. No acceleration of respiratory movements could be 

 shown to take place. 



Figure 4 shows the effect of small doses of acetone on the CO2 

 output. At first there is a marked increase, followed by a gradual 

 decrease, which is considerably higher than the normal. Larger 

 doses produce effects similar to smaller ones, only the decrease 



