AND ANIMAL LIFE. 265 



CCLXXXVIII. WILSON PBILIP has endea- 

 voured to ascertain in what manner the action 

 of the heart is influenced by the application of 

 cjiemical and mechanical agents applied to the 

 brain ; and he brings forward a great number of 

 experiments, which prove, that these occasionally 

 act powerfully on the motions of the heart. He 

 says, that these act through the nervous system. 

 I shall attempt to shew from his own experi- 

 ments, and from others which I have performed, 

 that it is more than probable that the effects are 

 communicated through the sanguiferous. 



CCLXXXIX. In applying spirits of wine or 

 opium to a small portion of the brain, no effects, 

 he says, were produced ; but as soon as these 

 were diffused over a large surface, the action of 

 the heart was affected. If we augment the sur- 

 face to which one of these agents is applied, we 

 include in the same proportion a greater number 

 of absorbents or capillary vessels of what kind 

 soever, and therefore the action of this organ is 

 more liable to be influenced, because a greater 

 quantity of the stimulus or sedative is absorbed 

 and transmitted to the heart, on whose nerves 

 it produces its peculiar effects. The greater num- 

 ber of the subsequent experiments demonstrate 

 the correctness of this opinion. Regarding the 

 circulation as the medium of these agents, and 

 the heart as influenced by the matters which the 

 blood had absorbed during the circulation, I 



