on ihe^^Lhnnsi ^vsttin: Of 



period ray oHseK'ii1fiotw''c6rr(fsf)on'(i' \Vith fhosd 

 of Dr. iBard's, 'blit lead to a i?te'cortclai 



slob';'^for*'ifiSeVidcrtt, tliat he bnly'nbticed 

 the state 6f the pulse' which was presented aftcff 

 the cessation of thc'prrmriry effect of opiums 

 and not the condition \\hi( h' t'visUd rltrrlnf^ 

 the action. 



I am no w enabled to account for the defect of 

 aj^jkarance of enc^eased action 'uj)cin the appli^ 

 catibn of opium to the hearts and stonlachs of 

 frogs. In all bodies endued wkh life, a certain 

 property is present by which ^hey are enabled 

 to receive the in'ipression of pMvers applied. ^ 



The Effect which results from the appli- 

 cation of powers so applied t6 this property '% 

 called action : confined to the' iiiuscular fibre^ 

 this property has been denominated irritabi- 

 lity: in the nerves it is called sensibility. The 

 late ingenious and philosophic Brown, dis- 

 tinguished this property by the teitn excitabi- 

 lity, expressing a general principle in the body 

 of receiving impressions, but without referring 

 it either to the nerves or muscular fibre in 

 particular. 



As this term appears to be very' compre- 

 hensive, we shall crave the liberty to employ 

 It In this place. Supposing then, all powers 

 applied, act upon this property, it is proved by 

 Experiments 38, 39, 40 & -tl, that in conse- 

 K 2 



