PHYSICAL AND LITERARY. 3^3 



«. The fympathy of the nerves de- 

 pends chiefly, and ahnoft entirely, on 

 their connexion at their origin. At 

 the fame time, it has appeared, that, in 

 feme places, neighbouring nerves aiore 

 readily fympathizethar: difrant ones. 



10. As the opiumhas afurprifing infla- 

 cnce over the heart and arterious fyftem, . 

 ■when diredlly applied to them.; and thefe 

 cflPedts, though greater, are fimilar to the 

 cfFedls of this medicine when abforbed : 

 We may infer, that, when it is abforbed, 

 mixed, and conveyed with the blood, its 

 cfFedls are almoft folely to be afcribed to 

 its operation on the nerves of the heart, 

 and veiTels through which it is carried. 

 And, by analogy^ the like is probable of 

 many other medicines. 



1 1. 1 am far from denying in the laft co- 

 rollary, that thefe medicines produce any 

 alteration on the texture of the fluids ; on 

 the contrary, I am perfuaded they do al- 

 ter them, and that, by lonp^ continued 

 ufe, thofe alterations may be To confide- 

 rable, as to affe(5t the animal oeconomy, 



though, 



