PHYSICAL AND LITERARY. 345 



2. It appears, at fir ft fight, very fur- 

 prifing, that fpirits applied to the hi^^'i 

 legs affed the animals much.fooner than 

 tlie lolution of opium applied in the.farne 

 way ; yet, when both ,ai"e poured into the 

 cavity of the abdomen, theopium produces 

 icsfuU efFeds fooner than the fpirits. To 

 explain the caufe of this wi^h certa-inty js 

 extremely difficult ; but one part of the 

 .jeafon may be, that the fpirits chiefly o- 

 perate, by being mixed and conveyed with 

 the blood, without poiTelTiagfo much the 

 virtue of difordering the whole nervous 

 fyftem by touching one part of it ; where- 

 as the opium poiTeffes this lafl power in 

 a very eminent degree ; and therefore, 

 where it is applied to a very large nervous 

 furface, or to the ends of the nerves, but 

 thinly covered with their coats, or with 

 membranes, its effeds are very fpeedy. 



E XPE R. III. 



Ap, in the firft experiment, the ardent 



fpirits applied to the hind legs rendered 



Vol. III. Xx tiie 



