64 



ANIMAL ELECTRICITY. LECTURE III. 



First Stage. 



Fig. 24 (869). — Augmented negative effect. 



Second Stage. 



Fig. 26 (710). — Augmented negative effect. Dimin- 

 ished positive after-effect. 



Third Stage. 



vuithouf-. ■ ' I 1 





fe 



11 ' 





lafter 



Fig. 28 (859). — Positive converted into negative effect. 



Third Stage. 



.'■M'l tlLilLllli .Mllininiii 



f CO 2 from, 



r without 



Fig. 30 (985). — Positive effect diminished. 



Influence of Carbon Dioxide on the Electrical Response of Nerve 



in its three stages. 



