on the Living System, ' 97 



proved that frogs are more easily afFccted by 

 stimulantii than those aniinals, whose cxcUabi- 

 ity is^npt so abundant, ^nd by Experiment 

 31, 32, 33 & 34, that young animals are 

 sooner affected by stimuli than adult ones : it 

 is further to be concluded, that the effect of 

 stimulants is directly as the excitability, and 

 inversely as the excitement. Also, it ii> proveS^ 

 by Experiment 2,J^;2g, 2? %c, Mi that opium 

 affects frogs more speedily tlian warm-blooded 

 animals ; and by Experiment 35 & 36, young 

 animals of warm blood more readily than adult 

 animals of warm blood, that the. effect of 

 opium likewise is directly as the excitability 

 and inversely as the excitement. 



As the comparison therefore has held good 

 in all those instances we have related, betwixt 

 opium and stimulants, and in the production of 

 those effects, which are the usual and principal 

 effects of the action of stimulants upon the 

 human body, we are led to the final conclu- 

 sion, that the appearances, exhibited by the 

 animal body under the influence of opium, 

 are directly analagous to those exhibited under 

 the action of a:ther and spirits of wine and 

 volatile alkali ; that as these power* are sti- 

 mulant, so in like manner, and depending 

 upon equal prn'>^-, '- '^'^'um stimulant. 



