ACTION OF POISONS. 139 



recourse to before the circulation has ceased. It 

 is worthy of notice, that under these circum- 

 stances the animal does not recover his sensi- 

 bility, nor his power of locomotion, until some time 

 after he has begun to breathe spontaneously ; and 

 hence we may conclude, that the transmission of 

 dark-coloured blood to the brain has not merely 

 a negative but a positive effect, in fact operating 

 on it in the same way as a narcotic poison. In 

 some instances the affection of the brain thus 

 produced continues so long that ultimate re- 

 covery does not take place ; the animal (if I may 

 be allowed the expression) dying a second time, 

 in consequence of the muscles of respiration 

 again ceasing to perform their office. These 

 observations are applicable to the human subject, 

 as well as to the inferior animals. 



I have elsewhere * recorded some experiments, 

 showing in what manner death is produced by 

 the discharge of an electric battery. It is not 

 out of place for me to refer to them on this 

 occasion, as the phenomena bore a very near 

 resemblance to those produced by the more 

 powerful narcotic poisons. 



* Lectures illustrative of various Subjects in Pathology 

 and Surgery, 1846, page 101. 



