Vegetable Narcotic Poisons. 55 



in man and dog. But when we compare their cerebral 

 hemispheres, the difference is great indeed. In man, 

 the sulci are very deep between the convolutions, for 

 extension of the grey matter and the corresponding 

 increase of blood supply. The following extract 

 from Chaveau's "Comparative Anatomy" will be 

 interesting before I proceed further with this 

 seemingly difficult subject: 



EXTRACT. 



" It has been attempted to establish in the predominance 

 of the encephalon the cause of the development of the 

 intelligence, and that the best measure of this predominance 

 is really the relation of the spinal axis to the encephalic 

 mass. The relations differ notably in each of the following 

 species : In the dog 1 : 5-14, cat 1 : 3-75, sheep 1 : 2-60, ass 

 1 : 2-40, pig 1 : 2-30, horse 1 : 2-27, ox 1 : 2-18." 



According to Quain's " Human Anatomy," the 

 relation of the spinal cord to the encephalon in 

 man is as 1 : 38. 



We have these further facts to help us on. 



I conceive, therefore, that in man the cerebrum is 

 more deeply irrigated with poisoned blood than can be 

 the case in the dog, and consequently, its myriads of 

 cells must suffer from more intimate and prolonged 

 action of the poison than in the dog ; hence, probably, 

 the more overwhelming annihilation of function, 

 resulting in death. 



This attempted explanation applies also to the action 

 of belladonna and atropine, which next follow : 



EXPERIMENT V. 



March 26, 1869. This experiment was devised to 

 see accurately what was the effect of the injection of 



ammonia had upon the Heart itself. 



E 2 



