276 NERVOUS FORCE. LECT. XIV. XV. 



by disposing the nerve of the frog upon the gastrocnemius 

 muscle of the leg. 



I have also tried the effect of washing the frog, in which 

 I had excited the inducteous contractions, many times in 

 pure water, in order to remove all traces of blood, or 

 other secreted liquids, which might be on the surface of its 

 muscles : and the induced contractions were still equally 

 manifested. 



I removed with a razor, OF better still, with scissors, a 

 layer of muscular substance, and then placed the nerve of 

 the galvanoscopic frog upon the internal surface of the mus- 

 cles, and still obtained induced contraction. 



The same phenomenon is also produced by disposing 

 the nerve of the galvanoscopie frog upon the muscle, in 

 such a manner that the extremity of the nerve is folded 

 upon the nerve itself, and forms a kind of closed circuit. 



I also endeavoured to satisfy myself whether these in- 

 duced contractions would continue when the nerve of the 

 galvanoscopic frog had not been cut. For this purpose I 

 prepared a frog, taking care to preserve the integrity of the 

 nerve, in the following way : after having skinned the ani- 

 mal, I removed the abdominal viscera, then the bones 

 and muscles of the pelvis, and lastly, those of the thigh, 

 taking care to leave the nerve of the thigh entire. I then 

 prepared another frog in the usual way, and placed it upon 

 the turpentine, as already described. Afterwards I put the 

 nerve of the galvanoscopic frog, thus prepared, upon the 

 thighs of the second. By exciting muscular contractions 

 in the latter, we obtained induced contractions like those 

 when we employed the galvanoscopic frog ; and moreover, 

 we observed simultaneous contractions in the muscles of 

 the back, and in the other leg. We shall have occasion 

 hereafter to return to this experiment, and therefore, 

 for the present, we shall content ourselves with stating, 



