258 NERVOUS FORCE. LiECT. XIV. XV. 



cautious in assuming such an inference, which is too often 

 adopted as one of the best demonstrated experimental 

 truths. 



Let us, in the first place, inquire whether with the instru- 

 ments, which physical science furnishes us, the electrical 

 current can be discovered in the nerves of a living animal ? 

 Can this current exist there, and if it does, would it be 

 under the requisite conditions to be endowed with the cha- 

 racters of the nervous force ? 



The muscular electric current, an which we have dwelt 

 at some length in one of the preceding lectures, is shown, 

 by experiment, to owe its origin to chemical actions going 

 on in the muscles. We have seen that this current exists 

 in the integrant parts of the muscles, as well as between the 

 molecules of two bodies which enter into combination; that 

 it circulates there without any regularity, and one might 

 say that, as Ampere imagined, it took place in magnetizable 

 bodies, and that it is only by an experimental arrangement 

 that we can discover the presence of this current. We 

 have also shown, that the nerves have no direct influence 

 over the production of this current, and that their office is 

 limited, in experiments on the muscular current,, to that of 

 a slightly conducting body, communicating with certain 

 parts of the muscle. 



No Electric Current in the Nerves. It was important to 

 search for the presence of an electric current in the nerves 

 of a living animal. I shall refrain from noticing here all 

 the experiments which have been undertaken with this 

 object in view, and which have terminated in the announce- 

 ment, at one time, that this current did exist .at another 

 time that it did not exist. The most conscientious and 

 best established conclusion is this : In the present state of 

 science, and with the means of experimenting which we at 



