274 NERVOUS FORCE. L.ECT. XIV. XV. 



render the contacts between the elements more perfect, and, 

 consequently, the interior conducting power of the pile, 

 ought to be augmented. Indeed, in the pile formed of en- 

 tire frogs, the contact between the elements is always im- 

 perfectly established, and we constantly observe great dif- 

 ferences in the intensity of the current produced by these 

 same elements, according to the greater or less care with 

 which they are arranged. 



Whatever may be the explanation given of the slight 

 augmentation manifested in the intensity of the proper cur- 

 rent, by touching the lumbar plexus of frogs with alkali, 

 and thereby exciting muscular contraction, it is certain that 

 this fact alone cannot prove that electricity is developed 

 during the muscular current ; the more so, as those before 

 mentioned lead us to the conclusion that this development 

 does not occur. 



Experiments on Induced Contractions. I pass now to the 

 exposition of the new and numerous experiments made 

 upon the phenomenon of induced contractions. However 

 extended, I do not think that I ought to pass them over 

 in silence, on account of the great importance of the prin- 

 cipal fact which they are designed to illustrate. 



It is sufficient to have seen once the phenomenon of 

 induced contraction obtained without having excited the 

 inducing contractions* by means of the electric current, to 

 be convinced that this is not the direct cause of induced 

 contractions. If, after having placed the nerve of the gal- 

 vanoscopic frog upon the muscles of another prepared in 

 the usual way, we rapidly tear the spinal marrow of the 

 latter, either with a pair of scissors, or a piece of glass, or 



* Henceforth I shall call, by way of analogy, the contraction inducing 

 or inducteous, in which the muscles are in contact with the nerve of the 

 gahanoscopic frog in which the induced contraction is developed. Note 

 i y Matteucci. 



