ofM. Flbnrens on the Navoiis system. 117 



tation does not cause it to contract ; but certainly they do not 

 pretend that it may not, therefore, produce irritation in the 

 muscle : theie is not an individual among them who has not 

 always known that the contrary is the fact. When they say 

 the nerve is sensible, they mean that the animal receives all its 

 sensations through the medium of the nerves ; but they cer- 

 tainly do not pretend that the nerve, separated fi-om the body, 

 can continue to communicate sensations to the animal, still less 

 that it can experience any itself. 



We shall begin, then, by entreating M. Flourens to ex- 

 punge from his excellent work an introductory part relative 

 to this nomenclature, and which can only tend to confuse 

 ideas, without any solid advantage to science. Thus, from 

 the lact that the nerve, when pricked, produces contractions 

 in the muscle, he concludes that the nerve is irritable : it is 

 sufficiently clear that, in this proposition, he gives us no new 

 information, but that he only changes the meriuing of the 

 word irritable. From the fact that the nerve sej^arated from 

 the rest of the system, no longer gives anj' sensation to the 

 animal, he concludes that the nerve is not sensible. This also 

 is simply the change of a word, which tells us nothing but what 

 we knew before. 



M. Flourens himself admits that he introduces a new lan- 

 guage ; for he says, " I call irritability the property which the 

 nerve has of exciting sensation and motion without experien- 

 cing them itself." Now to give to a word in common use, a 

 new sense, is always a dangei'ous proceeding. If it is neces- 

 sary to express a new idea, it is much better to invent a new 

 term than thus to distort an old one. 



What is true, what is independent of all verbal disputes on 

 this subject, is, that the fibre contracts, whether it be irritated 

 immediately, or whether the nerve be irritated ; that the nerve 

 is, consecjuently, a conductor of irritation ; that the animal feels 

 the impressions made upon its nerves when these have a free 

 commmiication with the encephalus; — that consequently the 

 nerve is a condnctor of sensation. These are the terms which 

 might be employed with advantage, in order to increase the 

 rigour of the received language; they are those, in fact, which 

 we shall use in the remainder of this Report. 



To ex))rcss then, in general language, the real questions 

 which M. Flourens has proposed to himself^ and which are 

 not, perhaps, de(ennined with sufficient clearness in the title 

 of his j5a})er; we will say, that he has endeavoured to ascertain 

 by experiment : 



1°. From what points of the nervous system artificial irri- 

 tation may i)rocce<l in order to reach the juuscle. 



2^ To 



