on the Living Sjjstem. 25 



action upon the blood, or that this fluid is an 

 insufficient medium to convey it to distant parts 

 of the system. Vid. Exp. 10th. 



The fourth series proves that the effect of 

 opium is directly exerted upon the nervous 

 system. Exp. 11th, 12th, and 13th. That in 

 proportion to the unity and integrity of this 

 system, the effects of ' opium are extended to 

 distant parts. Exp. 8th and 9th. That where 

 this integrity is only partial, the effects are only 

 partial. Vid. Exp. 16th. That where the 

 integrity is interrupted, the effect of opium is 

 interrupted. Exp. 15th. And finally, that the 

 7ina et indivisa proprietas of irritability is in- 

 adequate in any degree to extend or commu- 

 nicate the effegts or operation of the above- 

 mentioned power (y). 



(y) In Ihe Dissertation which has been so often quoted, 

 the above experiracnts will be found supported by many 

 others, the tendency of all which verge to the same point. 

 In that, the general criterion which waj established to 

 denote the influence of opium, was founded on the ob- 

 servation of convulsions preceding death, and the loss of 

 irritability in the muscular fibre after death. The quan- 

 tity of this remaining was denoted by the frequency and 

 strength of the contractions upon the application of 

 common salt. It was, after many (rials uith other sub- 

 stances, found to be the most certain and effectual test. 

 The manner in which salt produces this effect is no lc>i 

 beautiful than singular. It does not so much appear lo 



D 



